Open Collections

UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

Synthesis, structure and electrochemistry of thiopene-containing oligoacenes and metallated schiff base… Pietrangelo, Agostino 2008

Your browser doesn't seem to have a PDF viewer, please download the PDF to view this item.

Item Metadata

Download

Media
24-ubc_2008_fall_pietrangelo_agostino.pdf [ 4.66MB ]
Metadata
JSON: 24-1.0060813.json
JSON-LD: 24-1.0060813-ld.json
RDF/XML (Pretty): 24-1.0060813-rdf.xml
RDF/JSON: 24-1.0060813-rdf.json
Turtle: 24-1.0060813-turtle.txt
N-Triples: 24-1.0060813-rdf-ntriples.txt
Original Record: 24-1.0060813-source.json
Full Text
24-1.0060813-fulltext.txt
Citation
24-1.0060813.ris

Full Text

SYNTHESIS, STRUCTURE, AND ELECTROCHEMISTRY OF THIOPHENE-CONTAINING OLIGOACENES AND METALLATED SCHIFF BASE MONOMERS  by AGOSTINO PIETRANGELO Hon. B.Sc., Chemistry University of Toronto, 2002  A Thesis Submitted in Partial Fulfillment of The Requirements for the Degree of  DOCTOR OF PHILOSOPHY  in  the Faculty of Graduate Studies (CHEMISTRY)  THE UNIVERSITY OF BRITISH COLUMBIA August 2008  © Agostino Pietrangelo, 2008  ABSTRACT The syntheses, structures, and electrochemistry of novel thiophene-containing oligoacenes and metallated Schiff base monomers are reported. Bent anthradithiophenes (67-71) were prepared by the oxidative photocyclization of 1 ,4-dithienyl-2,5-divinylbenzenes (62-66) and their  structural,  spectroscopic,  and  electrochemical  properties  determined  by x-ray  crystallography, powder x-ray diffraction, cyclic voltammetry, and UV/vis absorption and fluorescence spectroscopies. The site-selective reactivity of the thiophene moieties enabled access to the diphenyl- and dialkyl-functionalized derivatives where the substituents significantly influence the solid-state packing order of the oligoacenes in single crystals and as thermally evaporated films. Cyclic voltammetry studies suggest that the parent 67 electrochemically polymerizes via an oxidative coupling mechanism through the thienyl c carbons affording a poly-oligoacene polymer, a feature that was not observed in the functionalized derivatives. Thiophene-containing  metallated  Schiff  base  monomers  were  electrochemically  polymerized on Earth (1 g) and in microgravity (0 g) and the microscopic order of the subsequent polymer films probed by measuring the magnitude of the third-order nonlinear optical susceptibility tensor possess lower  x 3)•  The metallated polymers grown under terrestrial conditions  x 3) values than those grown in microgravity where gravity induced convection  currents are suppressed, suggesting that buoyancy forces generated under terrestrial conditions disrupt the weak intermolecular interactions between polymer chains that ultimately give rise to improved microscopic order. Moreover, the  2 x 3) enhancements were found to vary between Cu  polymers grown in microgravity that differed only in the length of the peripheral alkoxy substituents indicating that in addition to the metal centres, the length of the alkoxy substituent  11  also influences the microscopic order of the polymer films. A series of Pd-containing oligothiophenes were electrochemically polymerized onto carbon fiber electrodes and their catalytic activity investigated through a variety of C-C cross-coupling reactions. The polymers possessed the same catalytically active Pd-sites but differed in their connectivity to the polythiophene backbone, a factor that influenced their electrochemistry and film quality. Poly-100 proved to be an efficient catalyst for intra- and intermolecular C-C crosscoupling reactions (i.e., Suzuki, Heck, Sonogashira). X-ray photoelectron spectroscopy and control experiments suggest that polymer and metal ion-leaching is negligible during the course of the reactions, proving that poly-100 is a heterogeneous catalyst.  111  TABLE OF CONTENTS Abstract  ii  Table of Contents  iv  List of Tables  vii  List of Figures  x  List of Schemes  xv  List of Charts  xvi  List of Symbols and Abbreviations  xvii  Acknowledgements  xxiii  Dedication  xxv  Co-Authorship Statement CHAPTER 1 1.1 1.2  1.3  1.4 1.5  Overview it-Conjugated Organic Materials 1.2.1 Electronic Properties of it-Conjugated Materials 1.2.2 Conductivity of Oligoacenes 1.2.3 Factors Influencing Charge Carrier Mobility of Oligoacenes 1.2.4 Substituted Oligoacenes it-Conjugated Hybrid Polymers 1.3.1 Electronic Properties of ic-Conjugated Materials 1.3.2 Conductivity of Oligoacenes 1.3.3 Factors Influencing Charge Carrier Mobility of Oligoacenes Goals and Scope References  CHAPTER 2 2.1 2.2  2.3  Introduction  Synthesis and Characterization of Novel Luminescent Bent Acenedithiophenes  Introduction Experimental 2.2.1 General 2.2.2 Synthesis Results and Discussion 2.3.1 Synthesis and Spectroscopy  xxviii I 1 2 2 4 6 9 15 15 19 22 27 28 37 37 39 39 41 52 52 iv  2.4 2.5  2.3.2 Cyclic Voltammetry 2.3.3 Oxidative Photocyclization of 2,5-dithienyl- 1 ,4-distyryl benzenes Conclusion References  CHAPTER 3 3.1 3.2 3.3  3.4 3.5  Introduction Experimental 3.2.1 General Results and Discussion 3.3.1 Solid-State Crystal Structures and Packing 3.3.2 Powder X-ray Diffraction Analyses of BADT Films 3.3.3 Solid-State Absorption and Luminescence Properties of Films Conclusion References  CHAPTER 4  4.1  4.2  4.3  4.4 4.5  5.3 5.4 5.5  Nonlinear Optical Properties of Schiff Base-Containing Conductive Polymers Electrodeposited in Microgravity  Introduction 4.1.1 Background 4.1.2 Chapter Objective Experimental 4.2.1 General 4.2.2 Collaborators 4.2.3 Synthesis Results and Discussion 4.3.1 Synthesis and Structure of Schiff Base Monomers 4.3.2 Electrochemical Polymerization of Schiff Base Monomers and Film Characterization 4.3.3 Electropolymerization in Microgravity 4.3.4 NLO Properties of Schiff Base-Containing Polymer Films Conclusion References  CHAPTERS  5.1 5.2  Solid-State Structures of Bent Anthradithiophene Single Crystals and Films  Electropolymerized Pd-Containing Thiophene Polymers Heterogeneous Catalysts for Cross-Coupling Reactions  Introduction Experimental 5.2.1 General 5.2.2 Collaborators Results and Discussion Conclusion References  .61 63 66 68 71  71 75 75 78 78 84 87 89 90 93 93 93 99 100 100 104 105 110 110 115 118 121 127 128 131 131 133 133 136 137 144 145 V  CHAPTER 6 6.1 6.2 6.3  Conclusions and Future Directions  General Conclusions Suggestions for Future Work References  147 147 150 155  APPENDIX 1  Crystal Structure Data  157  APPENDIX 2  Electronic Absorption Data of Schiff Base Monomers and and Polymers  185  APPENDIX 3  Cyclic Voltammograms of BADTs and Metallated Schiff Base Monomers  186  APPENDIX 4  NLO Data of Schiff Base Polymers  191  APPENDIX 5  ANOVA Analysis Results  194  APPENDIX6  ‘HNMRSpectra  194  vi  LIST OF TABLES  Table  2.1  UV-vis Absorption Data of Dialdehydes 57-61  56  Table  2.2  UVIvis Absorption Data of BADTs 67-71  59  Table  3.1  Bond Lengths of BADT 67  80  Table  4.1  IR absorption peaks of selected Schiff base complexes and their corresponding polymers.  116  Table  5.1  XPS analysis of poly-100  140  Table  Al-i Selected Crystal Structure Data for 57, 67, and 68  157  Table  Ai-2 Selected Crystal Structure Data for 69, 70, and 71  158  Table  Al-3 Selected Crystal Structure Data for 74, 90, and 91  159  Table  A1-4 Fractional atomic coordinates (x l0) and equivalent isotropic displacement parameters (A 2 x 1 0) for 74.  161  Table  A1-5 Bond lengths  Table  A1-6 Bond lengths (A) of 74 (continued)  163  Table  A1-7 Bond angles (deg) of 74  163  Table  A1-8 Bond angles (deg) of 74 (continued)  164  Table  Al-9 Anisotropic displacement parameters (A 2 x 10) for 74  165  Table Al-lO Fractional hydrogen coordinates (x 10) and isotropic displacement parameters (A 2 x 1 0) for 74.  166  (A) of 74  162  Table  Al-il Torsion Angles [deg] for 74  167  Table  Al-12 Torsion Angles [deg] for 74 (continued)  168  Table  A1-13 Fractional atomic coordinates (x 1 0) and equivalent isotropic displacement parameters (A 2 x 1 0) for 68.  169  Table  A1-14 Bond lengths (A) of 68  170  Table  Al-iS Bond angles (deg) of 68  171 vii  Table  A 1-16 Anisotropic displacement parameters  2 x 1 0) for 68 (A  172  Table  A1-17 Fractional hydrogen coordinates (x 1 O) and isotropic displacement parameters (A 2 x 10) for 68.  172  Table  A1-18 Torsion Angles [deg] for 68  173  Table  A1-19 Fractional atomic coordinates (x 1 0) and equivalent isotropic displacement parameters (A 2 x I 0) for 69.  174  Table  A1-20 Bond lengths (A) of 69  175  Table  A1-21 Bond angles (deg) of 69  176  Table  A1-22 Bond angles (deg) of 69 (continued)  177  Table  A1-23 Anisotropic displacement parameters (A 2 x 1 O) for 69  177  Table  A1-24 Fractional hydrogen coordinates (x 1 0) and isotropic displacement parameters (A 2 x 1 0) for 69.  178  Table  A 1-25 Torsion Angles [deg] for 69  179  Table  A1-26 Fractional atomic coordinates (x 1 0) and equivalent isotropic displacement parameters A 2 x I 0) for 71.  180  Table  A1-27 Bond lengths  Table  A1-28 Bond angles (deg) of 71  182  Table  A1-29 Anisotropic displacement parameters (A 2 x 10) for 71  183  Table  A1-30 Fractional hydrogen coordinates (x 1 04) and isotropic displacement parameters (A 2 x 10) for 71.  183  Table  A1-31 Torsion Angles [deg] for 71  184  Table  A2-1 Electronic absorption maxima Qrnax) of Schiff base complexes and their corresponding polymers.  185  Table  A4-1 NLO data for 6 ,poly-VOC poly-NiC poly-MFC , , 6 and poly-CuC . 6  191  Table  A4-2 NLO data for poly-MFC , poly-VOC 12 , 12 z, poly-NiC 1 and poly-CuC . 12  192  Table  A4-3 NLO data for P0IYCUCMeCy, poly-CuC , poly-CuC 8 , 14  193  (A) of 71  181  viii  Table  A5-1 ANOVA results from POlYCUCMecy, poly-CuC , 8 , and poly-NiC 12 poly-CuC 12 NLO data.  194  ix  LIST OF FIGURES Figure 1-1 Schematic of frontier molecular orbitals of benzene to pentacene  3  Figure 1-2 Simplified electronic band diagrams of anthracene (gas phase) anthracene (single crystal), and silicon (single crystal).  4  Figure 1-3 Charge injection into the HOMO of a p-type semiconductor and (b) charge injection into the LUMO of an n-type semiconductor.  5  Figure 1-4 (Top) Herringbone and (bottom) cofacial packing arrangement of pentacene showing HOMO interactions (Spartan ‘04, Wavefunction Inc.). Reprinted from reference 5 with permission from the American Chemical Society.  8  Figure 1-5 Edge-to-face packing arrangement of 4 with a (a) view down the short molecular axis and (b) view down the long molecular axis. (c) Face-to-face packing arrangement of 8 with isopropyl-groups omitted for clarity.  11  Figure 1-6 (a) Sandwich packing arrangement of 10. (b)Cofacial packing arrangement of 11. Chlorine atoms are green and hydrogen atoms are omitted for clarity.  12  Figure 1-7  t-Conjugated Polymers  15  Figure 1-8 ct- and p-positions of a thiophene molecule  16  Figure 1-9 Regiochemical Couplings in PATs  17  Figure 1-10 Three types of transition-metal-polythiophene hybrid materials  20  Figure 2-1 Thermal ellipsoid plot of 58. Thermal ellipsoids are drawn at 50% probability. The hydrogen atoms are omitted for clarity.  53  Figure 2-2 ‘H NIVIR spectrum of 58. (400 MHz, 2 CI ca. 25 °C) CD ,  54  Figure 2-3 Normalized solution phase UV/vis absorption spectra of 57-6 1 (top) and 62-66 (bottom) at Ca. 25 °C.  55  Figure 2-4 ‘H NMR spectrum of 63. (400 MHz, 2 C1 ca. 25 °C) CD ,  57  Figure 2-5 UV/vis absorption spectra of 71 recorded at 30s intervals during photolysis in benzene with dissolved iodine at ca. 25 °C.  58  Figure 2-6 ‘H NMR spectrum of 68. (400 MHz, 2 CI CD ,  60  Ca.  25 C)  x  Figure 2-7 Cyclic voltammetry of 67 in 2 C1 containing 0.1 M [(n- Bu) CH Nj 4 4 Scanned from +0.4 to + 1.3 V vs SCE for 10 cycles, SR = 100 mV s. C10  61  Figure 2-8 SEM micrograph of a poiy-67 film electrochemically grown onto a gold on glass wafer.  62  Figure 2-9 Thermal ellipsoid plot of 74. Thermal ellipsoids are drawn at 50% probability. The hydrogen atoms are omitted for clarity. (b) Packing diagram of 74.  65  Figure 3-1 Illustration of a top-contact OFET and the molecular layer structure of the conducting channel.  72  Figure 3-2 (a) Pitch angle (P) describing intermolecular slipping along the long molecular axis (view down short molecular axis). (b) Roll angle (R) describing intermolecular slipping along the short molecular axis (view down long molecular axis). (c) Long and short molecular axes of 67.  74  Figure 3-3 (a) Thermal ellipsoid plot of 67. The hydrogen atoms are omitted for clarity. Thermal ellipsoids are drawn at 50% probability. (b) View down the stacking axis of two cofacial molecules of 67. (c) Crystal packing of 67. Dashed lines illustrate short contacts (ca. 3.47 A) (d) View down the stacking axis of two cofacial molecules of 68.  78  Figure 3-4 Packing diagram of 69. (a) View along short molecular axis. The hydrogen atoms are omitted for clarity. Thermal ellipsoids are drawn at 50% probability. (b) View perpendicular to the molecular plane of the stacking axis. (c) Space-filling diagram of 69. Sulfur atoms are yellow, sp -hybridized carbon 3 atoms are grey, and sp -hybridized carbon atoms are purple. 2  81  Figure 3-5 (a) Thermal ellipsoid plot of 70. The hydrogen atoms are omitted for clarity. Thermal ellipsoids are drawn at 50% probability. (b) View down the “stacking axis” of two cofacial molecules of 70 with dodecyl chains omitted. (c) Space-filling diagram of 70 illustrating packing structure. Sulfur atoms are yellow, sp -hybridized carbon atoms are grey, and sp 3 -hybridized carbon atoms 2 are purple.  82  Figure 3-6 (a) View down the short molecular axis of 71. The hydrogen atoms are omitted for clarity. Thermal ellipsoids are drawn at 50% probability. (b) Crystal structure of 71 showing two of the eight close contacts between the edge of one acene and the face of another.  83  Figure 3-7 X-ray diffractograms and schematic representations of the structural orientation of (a) 67 and (b) 70 on glass substrates deposited by vacuum evaporation.  85  xi  Figure 3-8 X-ray diffractograms and schematic representations of the structural orientation of (a) 68 and (b) 69 on glass substrates deposited by vacuum evaporation.  86  Figure 3-9 (a) Solid-state UV/vis absorption spectrum of 67 (black-solid) Emission spectrum of 67 in solution (red-dash) and as a thin film (blue-dot). (b) Solid-state UV/vis absorption spectrum of 70 (black-solid). Emission spectrum of 70 in solution (red-dash) and as a thin film (blue-dot).  88  Figure 4-1 (a) Schematic of the relationship between electric polarization (F) and electric field (K). (b) Schematic of electronic transitions that give rise to THG.  94  Figure 4-2 Illustration of main chain orientation before and after stretching  96  Figure 4-3 Electric double layer formed as a result of polymerization at the electrode surface. Note the uneven distribution of product (polymer, red spheres), reactant (monomer, blue spheres) and counterions. (electrolyte, +,-).  98  Figure 4-4 (a) Thermal ellipsoid plot of 90 (NiCi ). Thermal ellipsoids are 2 drawn at 50% probability. The hydrogen atoms are omitted for clarity. (b) Packing diagram of 90, alkoxy chains and hydrogen atoms removed for clarity.  112  Figure 4-5 (a) Thermal ellipsoid plot of 91 (CuC ). Thermal ellipsoids are 12 drawn at 50% probability. The hydrogen atoms are omitted for clarity. (b) Packing diagram of 91, alkoxy chains and hydrogen atoms removed for clarity.  114  Figure 4-6 Cyclic voltammogram of 91 (CuC ) in DCM containing 0.1M 12 N]PF Scan rate = 100 mV/s. 4 [(n-Bu) . 6  116  Figure 4-7 SEM micrographs of(a) poly-MFC , (b) poly-VOC 12 , (c) 12 12 electrochemically grown films. , and (d) poly-CuC 12 poly-NiC  118  Figure 4-8 (a) Photograph of the Falcon 20. (b) Illustration of parabolic trajectory. (c) The author onboard the Falcon 20 in microgravity.  119  Figure 4-9 (a) Schematic and (b) photograph of the electrochemical instrument  120  3 x  Figure 4-10 Third-order susceptibility of metallated Schiff base polymers electrodeposited in microgravity (0 g, red squares) and in 1 g (blue circles).  122  Figure 4-11 Third-order susceptibility (3) of Cu 2 Schiff base polymers electrodeposited in microgravity (0 g, red squares) and in 1 g (blue circles).  125  3 x5  Figure 4-12 Third-order susceptibility of poly-CuC 12 Schiff base polymers electrodeposited onto working electrodes at 0, 90, and 180° relative to the gravitational field.  126  xii  Figure 5-1 Examples of Pd-mediated cross-coupling reactions  132  Figure 5-2 Cyclic voltammograms of(a) 100, (b) 101, and (c) 102 in DCM containing 0.1 M 6 N]PF Scan rate = 100 mV/s. 4 [(n-Bu) .  139  Figure 5-3 Normalized solution phase UV/vis absorption spectra of 100 (solid line) and poiy-iOO (dashed line) at ca 25 °C.  140  Figure Al-i Oak Ridge Thermal Ellipsoid Plot (ORTEP) of 74. Thermal ellipsoids are drawn at 50% probability.  160  Figure Al-2 ORTEP of 68. Thermal ellipsoids are drawn at 50% probability  169  Figure A1-3 ORTEP of 69. Thermal ellipsoids are drawn at 50% probability  174  Figure A1-4 ORTEP of 71. Thermal ellipsoids are drawn at 50% probability  180  Figure A3-l Cyclic Voltammogram of 68 in DCM containing 0.1 M [(nBu ) 4 NJPF Scan rate = 100 mV/s, 3 cycles. . 6  186  Figure A3-2 Cyclic Voltammogram of 69 in DCM containing 0.1 M [(nBu ) 4 NJPF Scan rate = 100 mV/s. . 6  187  Figure A3-3 Cyclic Voltammogram of 70 in DCM containing 0.1 M [(nBu ) 4 NjPF Scan rate = 100 mV/s. , 6  187  Figure A3-4 Cyclic Voltammogram of 89 (VOC, ) in DCM containing 0.1 M 2 )NPF Scan rate 100 mV/s. 4 ftnBu . 6  188  Figure A3-5 Cyclic Voltammogram of 89 (NiC ) in DCM containing 0.1 M 12 )NIPF Scan rate = 100 mV/s. 4 [(nBu . 6  188  Figure A3-6 Cyclic Voltammogram of 94 (CuC ) in DCM containing 0.1 M 8 )NJPF Scan rate = 100 mV/s. 4 [(nBu . 6  189  Figure A3-7 Cyclic Voltammogram of 95 (CuC ) in DCM containing 0.1 M 14 )NIPF Scan rate = 100 mV/s. 4 [(nBu . 6  189  Figure A3-8 Cyclic Voltammogram of 96 (CuCMecy) in DCM containing 0.1 M )N]PF Scan rate 100 mV/s. 4 [(nBu . 6  190  Figure A6-1 1 H NMR spectrum of 61. (400 MHz, 2 C1 Ca. 25 °C) CD ,  195  Figure A6-2 ‘H NMR spectrum of 66. (400 MHz, 2 C1 CD ,  25 °C)  196  Figure A6-3 ‘H NIVIR spectrum of 71. (400 MHz, 2 CI ca. 25 °C) CD ,  196  Figure A6-4 ‘H NMR spectrum of 72. (400 MHz, 2 C1 ca. 25 °C) CD ,  197  Ca.  xlii  Figure A6-5 ‘H NMR spectrum of 73. (400 JVIHz, 2 C1 Ca. 25 °C) CD ,  197  Figure A6-6 ‘H NMR spectrum of 74. (400 IVIHz, 2 C1 Ca. 25 °C) CD ,  198  Figure A6-7 ‘H NIVIR spectrum of 96. (400 MFIz, 2 C1 Ca. 25 °C) CD ,  198  Figure A6.-8 ‘H NMR spectrum of 97. (400 MHz, 2 C1 Ca. 25 C) CD ,  199  Figure A6-9 ‘H NMR spectrum of 98. (400 MHz, 2 C1 Ca. 25 C) CD ,  199  Figure A6-10 ‘H NMR spectrum of 90. (400 MHz, 2 C1 ca. 25 C) CD ,  200  xiv  LIST OF SCHEMES Scheme 1-1.9 Scheme 1-2  18  Scheme 2-1  52  Scheme 4-1  110  Scheme 4-2  123  Scheme 4-3  124  Scheme 5-1  141  Scheme 5-2  143  Scheme 6-1  151  Scheme 6-2  153  Scheme 6-3  154  xv  LIST OF CHARTS Chart 1-1  10  Chart 1-2  13  Chart 1-3  20  Chart 1-4  23  Chart 1-5  26  Chart 2-1  38  Chart 2-2  63  Chart 5-i.  ...  137  xvi  LIST OF SYMBOLS AND ABBREVIATIONS  2D  two-dimensional  0  degrees degrees Celsius  A  Angstrom  o  chemical shift frontier orbital energy gap molar extinction coefficient (M’ cm’) permittivity of free space  2’.  wavelength excitation wavelength  9  theta, angle charge carrier mobility  0 co  input frequency output frequency  v  frequency quantum yield linear susceptibility tensor quadratic susceptibility tensor cubic susceptibility tensor effective third-order nonlinear susceptibility xvii  third-order nonlinear susceptibility of silica acac  acetylacetonate  AFM  atomic force microscopy  Ar  aryl  au  arbitrary units  BADT  bent anthradithiophene  1 cm  wavenumber  CSA  Canadian Space Agency  CV  cyclic voltammetry  D  drain  d  doublet polymer sample thickness  dr  reference sample thickness  DCM  dichioromethane  dd  doublet of doublets  dec.  decomposition  DFT  density functional theory  DIPEA  diisopropylethylamine  DMA  dimethylacetamide  DMF  dimethylformamide  DMSO  dimethylsulfoxide  ee  enantiomeric excess  E  electric field xviii  EF  Fermi energy level  El  electron impact  EPR  electron paramagnetic resonance  equiv.  equivalent  ESI  electrospray ionisation  Et  ethyl  eV  electron volts  F  calculated structure factor  FrR  Fresnel factor for silica  Fj?  Fresnel factor for sample  FET  field effect transistor  0 F  observed structure factor  fs  femtoseconds  FT-IR  fourier transform infrared  g  grams  g  gravity  GC  gas chromatography  h  hour(s)  HH  head-to-head  HPLC  high performance liquid chromatography  HOMO  highest occupied molecular orbital  HRMS  high resolution mass spectrometry  HT  head-to-tail xix  IAR (w)  Institute for Aerospace Research incident beam intensity reference THG intensity  I  sample THG intensity  i-Pr  isopropyl  IR  infrared  ITO  indium tin oxide reference coherence length sample coherence length  LADT  linear anthradithiophene  LED  light emitting diode  LMW  low molecular weight  LUMO  lowest unoccupied molecular orbital  M  molar  m  multiplet  Me  methyl  m!z  mass/charge  MF  metal-free  MHz  megahertz  MoKcL  molybdenum Kc radiation  Mp.  melting point  MS  mass spectrometry  mV  millivolts xx  NLO  nonlinear optical  NvR  nuclear magnetic resonance  NRC  National Research Council  o  ortho  OAc  acetate  OFET  organic field effect transistor  OLED  organic light-emitting diode  ORTEP  Oak Ridge thermal ellipsoid plot  P  electric polarization  P  pitch angle  p  probability of a Type 1 error  p  para  PAT  polyalkylthiophene  Pd/C  palladium on carbon (catalyst)  Ph  phenyl  PLED  polymer light-emitting diode  PMT  photomultiplier tube  ppm  parts per million  PT  polythiophene  R  roll angle  Rf  retention factor  S  Siemens  S  source xxi  s  singlet  salen  2,2’-N,N’-bis(salicylidene)ethylenediamine  salphen  2,2’-N,N’-bis(salicylidene)phenylenediamine  SCE  standard calomel electrode  SEM  scanning electron microscopy  t  triplet  TEA  triethylamine  tert  tertiary  THF  tetrahydrofuran  THG  third harmonic generation  TLC  thin-layer chromatography  TOF  time of flight  IT  tail-to-tail  UV-vis  ultraviolet-visible  VSD  source-to-drain potential  VSG  source-to-gate potential  XPS  x-ray photoelectron spectroscopy  xxii  ACKNOWLEDGMENTS There are a number of people that I would like to thank who have made this thesis possible. First and foremost, I would like to thank my supervisors Professors Mark MacLachian and Michael Wolf. Their guidance, wisdom, and patience has carried me through my studies during the most successful and frustrating of times and for this I am eternally grateful. They are excellent mentors and confidants and our thoughtful discussions on chemistry and life will be missed. I am grateful to all of my co-workers in the Wolf and MacLachian groups, both present and past, who have shared with me my incredible experience at JJBC. I specifically want to thank Dr. Tracey Stott and Dr. Amanda Gallant for all of their support through the frustrating periods in the lab and who always brightened my day. I would like to express my gratitude to Matt Roberts, Dr. Bryan Sih, and Dr. Britta Boden for all of their assistance in making the flight campaigns in Ottawa as successful as they were. I would also like to acknowledge Tim Kelly and Tamara Kunz for always listening to my banter in the lab and at the pub  well mostly at  the pub. I would like to express my gratitude to Professor Pierre Kennepohi for reading this thesis in its entirety and for his invaluable advice on my future endeavors. I would like to thank Professor Dan Bizzotto for his work on the LabView program and for allowing me to use his JR Microscope and Tissaphern Mirfakhrai for his patience in training me on the AFM instrument. I am grateful to Professor K.C. Chou, our collaborator, for his useful discussions on nonlinear optics, and for all his contributions to the microgravity project. Many thanks to all of the members that operate the NMR, Microanalysis, Electronics, Mechanical, and Glass blowing facilities at UBC. A great deal of this work would not have been possible without their technical  xxiii  support. I am forever indebted to my wonderful loving parents who have always supported me in whatever I have pursued. Their love, guidance, and advice has shaped me into the person I am today. I am also grateful for the care packages (home made prosciutto, cheese, sausages, and olives shipped directly from the cantina of Casa Pietrangelo in Toronto. .sweet!). I am also .  indebted to my wonderful fiancée Desirae. She is my rock. I am grateful to be blessed with her unconditional love and patience. Finally, I would like to thank the Canadian Space Agency (CSA) and UBC for all of their financial support.  xxiv  DEDICATION This thesis is dedicated to Kristin Matkovich. My beautiful friend, I wish you all the best in the future.  xxv  CO-AUTHORSHIP STATEMENT A version of Chapters 2 and 3 has been published as a letter to the editor: Pietrangelo, A.; MacLachian, M.J.; Wolf; M.O.; Patrick, B.O. Org. Lett. 2007, 9, 3571-3573. I am the primary author and principal investigator of this work under the supervision of Professors Mark MacLachlan and Michael Wolf. Dr. Brian Patrick performed the x-ray crystallography experiments of compounds 58 and 67-71. A version of Chapter 4 has been published as a communication to the editor: Pietrangelo, A.; Sih, B.C.; Boden, B.N.; Wang, Z.; Li,  Q.;  Chou, K.C.; MacLachian, M.J.; Wolf; M.O. Adv.  Mater. 2008, In Press. I am the primary author and principal investigator of this work under the supervision of Professors Mark MacLachian and Michael Wolf. The contributions of the remaining authors are described in detail in section 4.2.2. “Collaborators”. A version of Chapters 5 has been published as a communication to the editor: Albano, V.G.; Bandini, M.; Moorlag, C.; Piccinelli, F.; Pietrangelo, A.; Tommasi, S.; Umani-Ronchi, A.; Wolf; M.O. Organometallics 2007, 26, 4373-4375. The work presented in this Chapter was done in collaboration with Professor Marco Bandini and his research team at the University of Bologna. I was one of the principle investigators and primary authors of this work under the supervision of Professor Michael Wolf. The contributions of the remaining authors are described in detail in section 5.2.2. “Collaborators”.  xxvi  CHAPTER 1 Introduction  1.1  OVERVIEW  On October 1st, 2007, Sony Corporation introduced the Sony XEL-1 OLED Television, the world’s first commercially available television that utilizes organic light-emitting diodes. The 11-inch screen boasts a modest weight of 2 kg, a thickness of 3 mm, and a contrast ratio of 1,000,000:1.1 This product is a prime example of the role that organic materials have in the evolution of technological devices that constantly demand higher device efficiencies, lower power consumption, and lighter weights. This driving force is fueling great interest in the field of organic materials in both academic and industrial institutions. The objective of this Chapter is to provide the concepts and background to the thesis. First, a general introduction to the electronic properties of t-conjugated organic materials with an emphasis on oligoacenes is given. The origin of their electronic properties and the factors that influence them will be discussed. This is followed by a literature review of oligoacenes that have been studied for their potential use in organic electronic devices. In the second half of this Chapter, a general introduction to polythiophenes and transition-metal-polythiophene hybrid materials is given. A summary of the types of materials and their useful properties follows. Finally, the goals and scope of this thesis are stated.  1  1.2 1.2.1  it-CONJUGATED ORGANIC MATERIALS Electronic Properties of it-Conjugated Organic Materials  it-Conjugated organic materials are studied extensively for their electronic and optoelectronic properties that are applicable in a variety of molecular electronic devices such as field effect transistors (FET5), chemical sensors, light-emitting diodes (LEDs), and solar cells. 2 These properties arise from the alternating single and double bonds between sp -hybridized carbon 2 atoms that form an extended it-conjugated system. A consequence of this bonding is the formation of electronic “bands” that give rise to highly desirable properties such as electrical conductivity and electroluminescence. 7 it-Conjugated organic materials are broadly categorized into two classes: low molecular weight (LMW) molecules and polymers. LMW it-conjugated organic materials typically consist of fused arenes, oligoacenes, and oligomers. Examples of oligoacenes and their simplified frontier molecular orbital energy diagrams are illustrated in Figure 1-1. Bonding and antibonding interactions between sp -hybridized carbon atoms give rise to splitting of the 2  it-  orbital energy levels and to delocalization of it-electron density. The energy of the highest occupied molecular orbital (HOMO) increases with the length of the oligoacene. This is accompanied by a reduction in energy of the lowest unoccupied molecular orbital (LUMO) and an overall reduction of the frontier orbital energy gap (.E). 7 This phenomenon is reflected by the UV/vis absorption maxima which shift to lower energies from benzene through pentacene. ’ 8 In addition, reductions in vibrational reorganization energies’°’  , 2 and ionization potentials’  and improvements in both charge carrier mobility 13 and conduction bandwidths’ 4 are expected 2  with increasing oligoacene size, thus making higher oligoacenes desirable for materials applications.  LUMO Energy  zXE  HOMO1,  1.  Q  0 benzene naphthalene anthracene tetracene  pentacene  Figure 1-1. Schematic of frontier molecular orbitals of benzene to pentacene.  Basic descriptions of the electronic energy levels of LMW it-conjugated organic materials in the crystalline state are approximated using the “orientated gas model”. 7 Going from the gas phase to the crystalline phase, molecular energy levels are moderately split into narrow bands by the weak van der Waals interactions between adjacent molecules in the lattice (Figure 1-2). This is reflected by the solid-state absorption and luminescence spectra of crystalline organic materials that exhibit similar features to their gas and solution phase spectra. 8 In contrast, the electronic coupling interactions in inorganic semiconductors such as silicon are much greater as a result of the covalent interactions that bind adjacent atoms. This gives rise to much broader  3  valence and conduction bandwidths and a three dimensional charge transport pathway in the material resulting in much larger conductivities. 15  LUMO Conduction Band Energy Va’ence Band HOMO  anthracene (gas phase)  anthracene (crystalline phase)  silicon (crystalline phase)  Figure 1-2. Simplified electronic band diagrams of anthracene (gas phase), anthracene (single  crystal), and silicon (single crystal).  1.2.2  Conductivity of Oligoacenes  Oligoacenes such as tetracene and pentacene behave as p-type semiconductors when holes are injected into the low-lying HOMO levels (Figure 1-3 a). 6 Under an applied external electric field, these charges become mobile allowing an electrical current to flow, n-Type oligoacene semiconductors such as perfluorotetracene and perfluoropentacene are generally prepared by perfluorination of oligoacenes.’ 8 In these semiconductors, electrons are the principal charge ’ 6 carriers and are injected into the LUMO levels (Figure 1 -3b). In field effect transistors, charge is 4  injected into the semiconductor from a metal electrode; hence, it is necessary that the work function (i.e., the minimum energy required to remove an electron from the Fermi energy level, EF,  into vacuum) of the electrode be matched to the HOMO energy of a p-type semiconductor or  the LUMO energy of an n-type semiconductor in order to have efficient charge-injection. 5 This can be accomplished by tuning the energy of the frontier orbitals via chemical functionalization. Charge carriers in oligoacenes can also be photo-generated when irradiated with a laser pulse.’ ’ 9 20  LUMO  (a)  LUMO EF  EHOMO__ Metal  Metal Organic Semiconductor  Metal  Metal Organic Semiconductor  Figure 1-3. (a) Charge injection into the HOMO of a p-type semiconductor, and (b) charge injection into the LUMO of an n-type semiconductor.  An important parameter that is intimately related to the conductivity and device performance of oligoacenes and other it-conjugated organic materials is charge carrier mobility  (ii),  the drift  velocity of the charge carrier per unit applied field (cm /Vs). Charge carrier mobilities of single 2 crystal oligoacene semiconductors such as naphthalene, ’ 21 ’ 25 pentacene  26  22  23 tetracene, anthracene, 24 and  have been shown to increase significantly with decreasing temperature, a 5  phenomenon that supports a band-like charge transport mechanism. 27 As with metals, the temperature dependence arises from lattice vibrations (phonons) in the single crystal that scatter charge carriers and reduce their mobility with the effects becoming more prevalent at higher 28 Due to the relatively weak electronic coupling in organic semiconductors, the temperatures. largest mobilities are found in highly ordered single crystals and reach a room temperature upper limit of 1-10 29 /Vs. In inorganic semiconductors where electronic coupling is strong, 2 cm mobilities can be as large as 1000 3 /Vs. 2 cm ° 1.2.3  Factors Influencing Charge Carrier Mobility of Oligoacenes  There are many factors that influence the charge carrier mobility of it-conjugated organic materials. These include impurities, ’ disorder (both diagonal and off-diagonal disorder), 3 3237 ’ 21 temperature,  36  ’ 38 pressure,  39  electric field, ’ 21  40  charge carrier density, ’ and crystal packing 4  43 ’ 42 motifs. Impurities in LMW it-conjugated organic materials generally dampen the charge carrier transport that is necessary for good device performance. For instance, single crystals of anthracene doped with tetracene have lower charge carrier mobilities compared to pure anthracene single crystals. This is a result of the frontier molecular orbitals of tetracene that fall within those of anthracene giving rise to hole-trapping states (see Figure 1-1 )•7  In higher  oligoacenes such as tetracene and pentacene, impurities are generally by-products carried over from synthetic processes or decomposition products generated from exposure to air and/or ’ 31 light.  46,  One example is 6,13-pentacenequinone 3 (Scheme 1-1), an oxidative  decomposition product of pentacene that has been shown to decrease the charge carrier mobility of single crystals of the latter. 25 6  The anisotropy of charge carrier transport observed in oligoacene single crystals suggests that mobility. 48, 49 This is a consequence of the ’ molecular packing also influences charge carrier 42 weak intermolecular electronic interactions in the lattice that vary with respect to a predefined crystal axis. LMW it-conjugated organic materials tend to crystallize into one of two common packing motifs. Benzene 51 and the oligoacenes naphthalene through ’ ’ 50 50 pentacene 5 2 adopt a 3 herringbone packing motif that is characterized by a layered edge-to-face packing arrangement where electronic coupling between the it-rich faces is limited (Figure 1-4 top). 5456 Theoretical studies have shown that this geometry is favourable when the systems are represented as sandwiches of positively charged a-frameworks flanked by two negatively charged it-electron 57 In this packing motif charge carrier transport anisotropy is observed where 2D charge clouds. transport within a stacked layer is more efficient than charge transport between layers. ° 586 Theoretical studies have also shown that electronic coupling in organic semiconductors is influenced by• small molecular displacements in the 6 lattice, 14 and help explain why charge carrier mobilities of some organic materials increase with pressures that induce crystalline phase 6567 transitions.  7  Q—-.  Figure 1-4. (Top) Herringbone and (bottom) cofacial packing arrangement of pentacene showing HOMO interactions (Spartan ‘04, Wavefunction Inc.). Reprinted from reference 5 with permission from the American Chemical Society.  Many efforts have focused on derivatizing oligoacenes in order to induce a slipped-stacked cofacial packing motif in the solid state (Figure 1-4 bottom). 5 Theoretical studies have shown that small displacements between adjacent molecules in a stack along the short and/or long molecular axis can significantly influence the electronic coupling between their n-electron rich ’ These effects have been linked to the shape of the HOMO and LUMO orbitals and the 6 faces. sign of the wavefunction that varies across the rigid t-conjugated framework. The same studies have also shown that the interplanar distances in a n-stack also play a key role in electronic coupling. 8  1.2.4  Substituted Oligoacenes  Pentacene is the most extensively studied oligoacene for thin-film field effect transistors due to its superior charge carrier mobilities and device performance. 68 It is prepared by the reduction of 6,13-pentacenequinone, obtained by a four-fold aldol condensation between phthalaldehyde and 1,4 cyclohexanedione (Scheme 1-1 )•69 Scheme 1-1  o  0 0H  +  I  o  0  2  3 Al  3  , Cd 2 HgCI 4  Despite its large charge carrier mobility, pentacene suffers from a variety of drawbacks. It is sparingly soluble in common organic solvents, thus largely limiting purification and device fabrication processes to vapour deposition methods. ’ 8  30  It is also both oxidatively and  photochemically unstable, and has a tendency to adopt multiple polymorphs in the crystalline state, all of which significantly influence charge carrier transport. 7072 In the past, improvements of these shortcomings were largely confined to advancements in device engineering, device fabrication, and chemical purification processes; 34 however, more recently, an alternative approach to maximize device performance has been to design new derivatized oligoacene materials. Through chemical modification, (1) improvements in both solubility and environmental stability are possible, (2) HOMO and LUMO energies can be tailored to improve 9  charge carrier injection, and (3) crystal packing motifs may by modified to enhance intermolecular electronic coupling interactions. Chart 1-1  (H3C)3SI)cSi(CH3)3 Ci (H S 3 )  Si(CH  4  5  3 SIR  6 7 8 9  R  R=Me R=Eth R=i-Pr R=Ph  —  R’  _•%  _%  —  —  10 11 12 13  R=C,R=H R=CI,R’=CI RBr,R’=H RBr,R’Br  Functionalizing pentacene with small alkyl substituents is one strategy that has been used to modif’ the electronic properties of the oligoacene without significantly perturbing its solid-state packing motif. For example, 2,3,9,1 0-tetramethylpentacene (4, Chart 1-1) was the first alkylated derivatized pentacene to be incorporated into an electronic device. 73 The weakly electron donating methyl substituents were found to increase the HOMO energy relative to pentacene while having little effect on the herringbone packing motif (Figure 1 -5a and b), a feature that was expected to improve hole injection. Unfortunately, the low oxidation potential resulted in an increase in chemical instability and may explain why there are few studies using alkylated pentacenes in organic electronics. 2,3,9,1 O-Tetrakis(trimethylsilyl)pentacene 5 was synthesized in an effort to prepare a highly soluble derivative using relatively small solubilizing groups. This 10  compound could not be isolated due to radical formation upon exposure to light and oxygen in Anthony and co-workers have developed a series of pentacene derivatives with 74 solution. silylethynyl groups on the pen positions of the oligoacene framework. 75 These compounds based on structure 6 are highly soluble, stable to oxidation in air, and exhibit varying degrees of cofacial  it-it  interactions in the crystalline state that can be controlled by altering the silyl  substituents. These compounds can be deposited onto electronic devices using thermal evaporation or solution processing techniques and exhibit good device performances.  (a) 1JJjX  (b)  xxxxxx xcccxx 5r556 (c)  Figure 1-5. Edge-to-face packing arrangement of 4 with a (a) view down the short molecular  axis and (b) view down the long molecular axis. (c) Face-to-face packing arrangement of 8 with isopropyl-groups omitted for clarity.  11  Halogenation of an oligoacene has been shown to significantly influence solid-state packing 77 For instance, chioro- and bromo-derivatized tetracenes 10 and 12 adopt ’ 76 in the single crystal. a sandwich-herringbone packing motif where dimers comprised of two molecules in a cofacial stack interact with adjacent molecules in an edge-to-face arrangement (Figure 1 -6a). In contrast, the dihalogenated derivatives 11 and 13 adopt a slipped cofacial 7t-stacking arrangement in the single crystal (Figure 1 -6b) and exhibit charge carrier mobilities nearly three orders of magnitude larger than their monohalogenated derivatives. The results of this work suggest that st-stacking does enhance it-orbital overlap that leads to improved charge carrier transport.  (a)  (b)  Figure 1-6. (a) Sandwich packing arrangement of 10. (b) Cofacial packing arrangement of 11.  Chlorine atoms are green and hydrogen atoms are omitted for clarity.  12  Aryl-substituted oligoacenes are a class of LMW 71-conjugated organic materials that have been studied extensively due to the influence that aryl substituents have on the solid-state packing and environmental stability of the oligoacene framework. For instance, rubrene (14, Chart 1-2) adopts a cofacial 7t-stacking packing arrangement in the single crystal which exhibits one of the largest single-crystal charge carrier mobilities measured for a phenyl-derivatized ° In addition, the phenyl substituents prevent the oxidative decomposition of 788 oligoacene. rubrene to its quinone analogue.  Chart 1-2  R  R  14  15 16 17  18  R=Ph,R’=H RPh,R’=Ph R = 2-thienyl, R’  =  2-thienyl  19 20  R=H R=Ph  13  Nuckolls and co-workers have prepared a series of aryl-substituted pentacenes (15-20, Chart 1-2) and investigated how the aryl substituents influenced packing in the single crystal and charge carrier mobility in field effect transistors. 81 The authors concluded that packing in the single crystal is dictated by the edge-to-face intermolecular interactions between C-H groups of the pendant phenyl rings and carbon atoms of the pentacene framework, a feature that becomes more prevalent as the number of phenyl substituents increases. Interestingly, the diphenyl- (16) and decaphenyl-derivatives (20) were found to adopt a herringbone packing motif where the pentacene moieties between adjacent molecules were isolated from one another. These compounds possessed lower charge carrier mobilities compared to the tetraphenyl- (18) and hexaphenyl-derivatives (19) where the acenes were in close contact. The dithiophene derivatized pentacene (17) adopts a cofacial stacking arrangement in the single crystal and field effect transistors incorporating this organic semiconductor exhibit the largest charge carrier mobilities of the entire series. The results of this work exemplif’ the relationship between charge carrier transport and solid-state packing. Incorporating heteroarenes such as thiophene into oligoacenes has also been part of an ongoing effort to prepare new materials with improved device performances. For example, Katz and co-workers prepared a series of linear anthradithiopenes (LADT5) that are structurally analogous to pentacene. ’ These heteroacenes are prepared as a mixture of syn and anti isomers 3 that form highly ordered polycrystalline films grown via vacuum evaporation. Hole mobilities of LADTs approach that of thin-film pentacene (1 cm IVs) while showing improved oxidative 2 stability. In addition, theoretical studies have suggested that increasing the cofacial interaction between LADT molecules could lead to improved device perfonnances. 64 Anthony and co workers have prepared a series of silylethynyl-functionalized LADTs that have improved 14  solubilities and favourable solid-state packing 82 motifs. 83 More importantly, thin films of these ’ compounds are processable from solution and exhibit good hole mobilities that can be further improved by annealing the films with solvent vapour. 84 Developing new materials of this class for semiconductor applications is a primary objective in this thesis and will be the topic of Chapters 2 and 3.  1.3  it-CONJUGATED HYBRID POLYMERS  1.3.1  Introduction to Polythiophenes  7t-Conjugated polymers are a class of organic materials that are studied extensively for their electronic and optoelectronic properties. As in oligoacenes, their functional properties arise from valence and conduction bands that are formed from alternating single and double bonds, resulting in a delocalized t-system. Examples of some it-conjugated polymers are shown in Figure 1-7.  polythiophene polypyrrole poly(p-phenylen evi nyle ne)  polyaniline  Figure 1-7. it-Conjugated polymers.  Polythiophenes (PTs) are environmentally and thermally stable polymers that are promising candidates as active materials in nonlinear optical devices, antistatic coatings, smart windows, solar cells, and transistors. 85 They are characterized by the covalent linking of thiophene molecules through their a- or n-carbon atoms (Figure 1-8). Unsubstituted oligo- and 15  polythiophenes with all a-linkages adopt a more planar conformation than those with a-f3- or 313-linkages leading to better it-orbital overlap and improved 85 conjugation. 8 ’ 6 As the length of the oligomer chain increases, the energy of its HOMO increases while zE decreases giving rise to a bathochromic shift of  ?max  in the electronic absorption spectrum ’ 86  87  and  lower oxidation  potentials in the cyclic voltammograms. 88 Unsubstituted PT is insoluble in common organic solvents and lacks processability, hence monomers are often derivatized at the 13-position with linear alkyl substituents. It should be noted that as a result of the asymmetry of the monomer, there are three possible a-a-coupling orientations (head-to-tail (HT), head-to-head (HH), and tail-to-tail (TT) coupling) that give rise to four chemically distinct triad regioisomers in the polymer chain (Figure 1 ..9)89  9°  The  regioregularity of the polyalkyithiophene (PAT) influences the effective conjugation length along the polymer backbone where steric interactions between alkyl substituents can lead to large torsion angles between adjacent thiophene units giving rise to poor orbital overlap, wider bandgaps, and lower conductivity. Regioregular (HT-HT) PATs have been shown to exhibit larger conductivities and lower optical bandgaps compared to irregular PATs and are thus more 88 For instance, p-doped regioregular (HT-HT) PATs exhibit popular for materials applications. conductivities (>1000 S/cm) that are comparable to bulk copper. 92 ’ 91  0:; Figure 1-8. a- and 13-position of a thiophene molecule.  16  HT-HT  HT-HH  TT-HT  TT-HH  Figure 1-9. Regiochemical couplings in PATs.  PTs and PATs can be prepared using a variety of methods and a thorough discussion of this topic is beyond the scope of this thesis. For an excellent review of the many preparative methods, see references 85 and 86. In short, thiophenes and alkylthiophenes are polymerized using chemical or electrochemical methods. Chemical oxidative coupling methods typically employ transition metal halides such as FeCl 3 as the oxidant and yield high molecular weight polymers with low regioregularity. 9397 The McCullough 98 and Rieke 99 methods of polymerization are based on the metal-catalyzed cross-coupling of organo-magnesium and organo-zinc reagents respectively. These reactions are versatile, high yielding, and afford regioregular PATs of low polydispersity with improved optical and electronic properties. Electrochemical methods of polymerization offer some advantages over chemical synthetic processes. For instance, the absence of catalyst ensures that there are no transition metal impurities that have been shown to affect the electronic and optoelectronic properties of PT 17  films in devices.’ ’ 00  101  Thin films are grown directly onto a conductive substrate enabling their  facile preparation, purification, and characterization. In addition, film thickness and morphology may be controlled by varying reaction conditions and electrochemical parameters.’° 2 The accepted mechanism of the oxidative polymerization of thiophene is illustrated in Scheme 12  102, 103  The polymerization process is initiated with a one-electron oxidation of the  monomer yielding a radical cation. The coupling of two radical cations affords a dihydro-dimer that undergoes rearomatization upon the loss of two protons. Oxidation of the dimer followed by coupling to a third radical cation affords a trimer that undergoes rearomatization. This process is believed to continue until the polymer becomes insoluble and deposits onto the surface of the electrode. This method of polymerization is key to the work presented in Chapters 4 and 5 of this thesis where the synthesis, nonlinear optical, and catalytic properties of novel inorganic organic hybrid polymers will be discussed. Scheme 1-2  2  (ji  ye 2  2H  +ve potential  Oi:  -&  -2H  18  1.3.2  Transition-Metal-Polythiophene Hybrid Materials  The electronic and optoelectronic properties of it-conjugated organic polymers such as PT can be tuned by synthetic modification of the polymer backbone ’ 85  98, 104, 105  and/or by the  modification of processing 9 ’° An alternative approach has been to incorporate 6 techniques.’° transition-metal complexes that can introduce or enhance the optical, electronic, or electrocatalytic properties of the bulk  10, 111  The Wolf and MacLachlan groups are  interested in materials based on transition-metal-polythiophene hybrids prepared using electrochemical methods. Transition-metal-polythiophene hybrid materials are broadly categorized into three classes that are differentiated by the arrangement of the metal centre relative to the conjugated polymer backbone (Figure 1_1O).h12 Hybrid polymers are classified as “Type I” materials if the metal centre is tethered to the backbone by a linker, typically a saturated organic group. In these materials, the metal centre is not part of the conductivity pathway of the conjugated polymer, though electronic communication can exist due to inductive effects.” 3 Polymers 21 and 22 (Chart 1-3) are examples of Type I materials. In their work, Zotti and co-workers demonstrated that the length of the alkyl chain tether influenced both the redox properties of the material and its conductivity. This has been attributed to an outer-sphere electron transport mechanism that shifts from a process involving ferrocene-to-ferrocene self exchange when a long saturated organic linker is used (22) to a mechanism involving the conjugated backbone when a shorter tether length is used (21).””  19  M (31  .  1%)  F’.) ()  a)  II  3  F’., 1’.)  -  3  -  1’.3  +  r%)  .  I  cr 1  CD  CD  -  —  0 —  (  D  CD  0  C,)  I -o  Co  II  CD  ‘C D 0  0  3  0  -o  dull CD  -o  T DI  ‘  I  I  ii4ihI  =  CD  -o  Transition-metal-polythiophene hybrids with metal centres coordinated directly to the polymer backbone are classified as “Type II” materials (Figure 1-10). In this class, direct electronic communication between the metal centre and the conjugated polymer is possible. For instance, 1.JV/vis absorption spectroscopy and cyclic voltammetry studies on the model complex 23 (Chart 1-3) indicate that the Ru 2 centre affects the electronic structure of the oligothiophene moiety, which can be switched between two states depending on the ligand-metal binding ’ 6 mode.”  117  More recently, Chen and co-workers developed a photoluminescent lanthanide  conducting metallopolymer (24) that exhibits energy transfer from the polymer backbone to the 3 centre. Since emission is purely metal-based, these materials are promising for polymer Eu light-emitting diode (PLED) applications that require high colour purity.” 8 Finally, “Type III” materials are those where the metal centre is coordinated directly into the polymer backbone enabling strong inner-sphere electronic coupling between the two 113 Electronic and vibrational spectroscopic data of the model complex 25 suggest that moieties. the ruthenium centre interacts electronically with the oligothienyl ligands resulting in lower energy it-c transitions in the latter and stabilization of the ruthenium centre in the 3+ oxidation state. This complex has been electrochemically polymerized though the nature of the polymer structure is unknown.” 9  21  1.3.3  Schiff Base —Containing Conductive Polymers  Schiff base complexes are a broad class of coordination compounds that are attractive for materials applications due to their nonlinear optical, electroluminescent, magnetic, and catalytic ° Much of their allure stems from the facile formation of the chemically robust 2 properties.’ proligand generated from the Schiff base condensation of a diamine with two molar equivalents of a salicylaldehyde. This reaction allows access to a variety of ligand architectures with tuneable optical and electronic properties. In addition, the high coordination affmity of the N 0 2 binding pocket (comprised of two imines and two phenoxides) for a variety of transition metals provides a second avenue through which the chemical and physical properties of the complex can be tailored. It is natural then to assume that there are many examples in the literature where Schiff base complexes have been incorporated into polymers affording hybrid materials with new and exciting properties. This section will focus on the polymers of this class prepared using electrochemical methods. A review by Leung and MacLachlan presents a complete account of Schiff base-containing polymers prepared by chemical methods. ° 12 The first Schiff base complexes to be electrochemically polymerized were reported by Murray and co-workers in 1988 (26) where coupling of the monomeric units was believed to occur through the aniline moieties in a tail-to-tail fashion.’ ’ The structure of the polymer was 2 confirmed by the closeness of the anodic potentials required to induce the oxidative electropolymerization of the monomers and to induce the oxidative coupling of two N-N dimethylaniline molecules to form N, ]V N’, N’ —tetramethylbenzidine 27. The lack of conjugation in the polymer backbone is evident in the cyclic voltammograms traces of the Co and Ni polymers that were found to be similar to their corresponding monomers.  22  Chart 1-4  C 3 (H N 2 ) _Q-_-Q—N(CH )  M  =  , 2 Ni  2+  2 Mn  26  27  N\ N=\ _NiD  29  28  M  =  2 , Co 2 Zn , Cu 2  30  M = Ni 2 Cu 2  31  Electropolymerization of a nickel N,N’-bis(salicylidene)ethylenediamine (salen) complex was demonstrated by Goldsby and co-workers and is one of the earliest examples of a Type III material of this class  (28).122  Blocking experiments using methyl substituents provided indirect  evidence that monomer coupling occurred mostly through the carbon atoms para to the phenolic oxygens. These results were later corroborated by Audebert and co-workers who isolated bis(salicylaldehyde) (29) by the demetallation of 28 followed by imine cleavage in concentrated 23  aqueous hydrochloric acid. The polymerization mechanism was investigated by Vilas-Boas and co-workers by performing in-situ EPR experiments on the polymer films. The results of their study indicated that electropolymerization was a ligand-based process, supporting a ligand radical coupling mechanism first proposed by Goldsby. UV/vis and FTIR spectroscopic studies on oxidized and neutral films revealed that the electronic properties of 28 are similar to polyphenylene whereby the main charge carriers are paramagnetic radicals in the form of polarons in the band gap. In later studies, films of 28 when reduced to the Ni form in the presence of acetic acid have been shown to catalyze the reduction of halo- and dihaloalkanes) ’ 23 124  By incorporating an Fe 3 or Co 2 metal centre into the N 0 binding pocket instead, the films 2  are able to catalyze the electrochemical reduction of hydrogen peroxide and dioxygen to ’ 125 water.  126  These results exemplify the versatility of Schiff base-containing polymers as  heterogenous catalysts. The first metallated Schiff base-containing polythiophene hybrid materials were prepared by Reynolds and co-workers by electrochemically polymerizing monomers prepared by the condensation of various salicylaldehydes with 3 ‘,4’-diamino-2,2 ‘:5 ‘,2 “-terthiophene, followed by metallation with copper, cobalt, or zinc salts  (30).127129  These polymers are classified as Type II  materials. The colour and redox potentials of the monomers and polymers were found to be unique to the metal centre, as were the electrochromic properties of the polymer films indicating that the metal centres are in electronic communication with the polythiophene backbone. Using methyl-blocking substituents on the terthiophene moieties enabled polymerization of the monomers through the salicylidene rings affording Type III materials. The same group has also developed polymer sensors (31) by electropolymerizing Schiff base complexes that have crown ether-like macrocycles incorporated into the ligand.’ ° The redox potentials of the polymer films 3 24  were found to shift upon the complexation of alkali and alkaline earth metals to an extent that was unique to each ion type. In addition, the crown complexed polymers were also found to detect donor molecules such as pyridine and triphenyiphosphine at nanomolar concentrations. Swager and co-workers have developed a family of Type III salen-based polymers (32-47, Chart 1-5) and studied how the steric bulk of the diimine substituents influenced the electronic properties of the thin films.’ ’ Using a variety of techniques that included cyclic voltammetry, 3 UV-vis spectroelectrochemistry, and EPR spectroscopy, the authors where able to conclude that the most sterically encumbered diimine bridges prevented It-aggregation between polymer chains resulting in poor inter-chain electronic communication and lower conductivities. Specifically, the conductivities for the Ni 2 and Cu 2 polymers decreased in the order of 32, 36, 39, 42, and 45 and 33, 37, 40, 43, and 46. These effects were also found to be metal dependant with the Ni 2 polymers showing less sensitivity to the ligand structure compared to the Cu 2 polymers. This group has also demonstrated that thin films of the Co 2 polymer (35) can catalyze the reduction of dioxygen to water 132 and be employed as reversible resistivity sensors for nitric oxide.  133  25  Chart 1-5  N)<  3-?  PN  32  M  33  M=Cu  =  2 Ni  2 34M=uo  36  M  =  2 Ni  37MCu2  39  M  =  2 N  40M=Cu2+  2 41 38M=uo  42 M =  2 Ni  43M=Cu2+  2 44M=UO M=UO 2  45 M = Ni 2 46M=Cu2+  2 47M=uo  2 35MCo  26  1.4  GOALS AND SCOPE  There were three principal goals to this thesis. The first goal was to develop a new family of soluble and oxidatively stable thiophene-containing oligoacenes for organic semiconductor applications in field effect transistors. Chapter 2 describes in detail the synthesis, spectroscopic characterization, and electrochemistry of a novel bent anthradithiophene (BADT) and a series of dialkyl and diphenyl functionalized derivatives. In Chapter 3, the solid-state structure and packing motifs of the BADTs as single crystals and polycrystalline thin films grown via thermal evaporation is discussed. The second goal was to investigate the effects that convection currents have on the microscopic order of Type III Schiff base-containing polythiophene hybrid polymer films grown via electropolymerization. It has been proposed that the gravity-driven convection currents that are generated at the electrode surface during polymerization can influence polymer deposition processes giving rise to thin films of poor quality and low order. Hence, we anticipated that thin films of higher quality could be grown by performing the same experiments in the absence of gravity, a task that has been virtually unexplored. The third and final goal of this thesis was to electrochemically synthesize Type I and Type Il-like Pd-complex polythiophene hybrid polymers as heterogenous catalysts for Suzuki, Sonogashira, and both inter- and intramolecular Heck cross coupling reactions.  27  1.5 1.  REFERENCES http://www.sony.net/SonyInfo/News/Press/2007 10/07-1001 E/index.html.  In  Sony  Corporation: 2008. 2.  McQuade, D, T.; Pullen, A. E.; Swager, T. M., Chem. Rev. 2000, 100, 2537-2574.  3.  Heeger, A. J., Angew. Chem.  4.  MacDiarmid, A. G., Angew. Chem.  5.  Anthony, J. E., Chem. Rev. 2006, 106, 5028-5048.  6.  Anthony, J. E., Angew. Chem.  7.  Karl, N., Organic Electronic Materials: Conjugated Polymers and Low Molecular  mt. Ed 2001, 40, 2591-2611. mt. Ed. 2001, 40, 258 1-2590.  mt. Ed. 2008, 47, 452-483.  Weight Organic Solids. Springer-Verlag: Berlin, 2001; p 2 15-240. 8.  Brutting, W., Physics of Organic Semiconductors. Wiley-VCH Verlag GmbH & Co.  KGaA: Weinham, 2005; p 1-12. 9.  Pope, M., Swenberg, C.E., Electronic Processes in Organic Crystals. Clarendon Press:  Oxford, 1982; p 1-38. 10.  Deng, W.-Q.; Goddard, W. A., 111,1 Phys. Chem. B 2004, 108, 8614-8621.  11.  Coropceanu, V.; Malagoli, M.; da Silva Filho, D. A.; Gruhn, N. E.; Bill, T. G.; Bredas, J.  L., Phys. Rev. Lett. 2002, 89, 275503/1-275503/4. 12.  Deleuze, M. S.; Claes, L.; Kryachko, E. S.; Francois, 3. P., 1 Chem. Phys. 2003, 119,  3106-3119. 13.  Cheng, Y. C.; Silbey, R. J.; da Silva Filho, D. A.; Calbert, 3. P.; Comil, J.; Bredas, J. L.,  I Chem. Phys. 2003, 118, 3764-3774. 14.  Brocks, G.; van den Brink, 3,; Morpurgo, A. F., Phys. Rev. Lett. 2004, 93, 146405/1-  146405/4. 28  15.  Gamier, F., Chem. Phys. 1998, 227, 253-262.  16.  Sakamoto, Y.; Suzuki, T.; Kobayashi, M.; Gao, Y.; Inoue, Y.; Tokito, S., Mo!. Cryst.  Liq. Cryst. 2006, 444, 225-232. 17.  Sakamoto, Y.; Suzuki, T.; Kobayashi, M.; Gao, Y.; Fukai, Y.; Inoue, Y.; Sato, F.;  Tokito, S., J Am. Chem. Soc. 2004, 126, 8138-8140. 18.  Inoue, Y.; Sakamoto, Y.; Suzuki, T.; Kobayashi, M.; Gao, Y.; Tokito, S., Jpn. I App!.  Phys. 2005, 44, 3663-3668. 19.  Kepler, R. G., Phys. Rev. 1960, 119, 1226-1229.  20.  LeBlanc, 0. H., Jr., I Chem. Phys. 1960, 33, 626.  21.  Warta, W.; Karl, N., Phys. Rev. B. 1985, 32, 1172-1182.  22.  Schein, L. B.; Duke, C. B.; McGhie, A. R., Phys. Rev. Lett. 1978, 40, 197-200.  23.  Karl, N.; Marktanner, J., Mo!. Cryst. Liq. Cryst. Sd. Tech. Mo!. Cryst. 2001, 355, 149-  173. 24.  de Boer, R. W. I.; Jochemsen, M.; Klapwijk, T. M.; Morpurgo, A, F.; Niemax, J.;  Tripathi, A. K.; Pflaum, J., I App!. Phys. 2004, 95, 1196-1202. 25.  Jurchescu, 0. D.; Baas, J.; Paistra, T. T. M., App?. Phys. Lett. 2004, 84, 306 1-3063.  26.  Thorsmolle, V. K.; Averitt, R. D.; Chi, X.; Hilton, D. J.; Smith, D. L.; Ramirez, A. P.;  Taylor, A. J., App!. Phys. Lett. 2004, 84, 89 1-893. 27.  Smart, L., Moore, E., So!id State Chemistry. Stanley Thomes Ltd.: Cheltenham, 1998; p  136-158. 28.  Pope, M., Swenberg, C.E., Electronic Processes in Organic Crystals. Clarendon Press:  Oxford, 1982; p 337-374.  29  29.  Pope, M., Swenberg, C.E., Electronic Processes in Organic Crystals and Polymers. 2nd  ed.; Oxford University Press: Oxford, 1999; p 337-340. 30.  Dimitrakopoulos, C. D.; Malenfant, P. R. L., Adv. Mater. 2002, 14, 99-117.  31.  Laquindanum, J. G.; Katz, H. B.; Lovinger, A. J., I Am. Chem. Soc. 1998, 120, 664-672.  32.  Borsenberger, P. M.; Fitzgerald, 3. J., I Phys. Chem. 1993, 97, 4815-4819.  33.  Dieckmann, A.; Bassler, H.; Borsenberger, P. M., I Chem. Phys. 1993, 99, 8136-8141.  34.  Dimitrakopoulos, C. D.; Mascaro, D. 3., IBMI RES. & DEV 2001,45, 11-27.  35.  Dunlap, D. H.; Parris, P. E.; Kenkre, V. M., Phys. Rev. Lett. 1996, 77, 542-545.  36.  Karl, N.; Kraft, K. H.; Marktanner, 3.; Munch, M.; Schatz, F.; Stehie, R.; Uhde, H. M., I  Vac. Sd. Technol., A 1999, 17, 23 18-2328. 37.  Sirringhaus, H., Adv. Mater. 2005, 17, 2411-2425.  38.  Liu,  39.  Chandrasekhar, M.; Guha, S.; Graupner, W., Adv. Mater. 2001, 13, 6 13-618.  40.  Mozer, A. J.; Sariciftci, N. S., Chem. Phys. Lett. 2004, 389, 438-442.  41.  Pasveer, W. F.; Cottaar, 3.; Tanase, C.; Coehoorn, R.; Bobbert, P. A.; Blom, P. W. M.;  C.-y.; Bard, A. J., Nature (London) 2002, 418, 162-164.  de Leeuw, D. M.; Michels, M. A. 3., Phys. Rev. Lett. 2005, 94, 206601/1-206601/4. 42.  Lee, J. Y.; Roth, S.; Park, Y. W., App?. Phys. Lett. 2006, 88, 252106/1-252106/3.  43.  Sundar, V. C.; Zaumseil, J.; Podzorov, V.; Menard, E.; Willett, R. L.; Someya, T.;  Gershenson, M. B.; Rogers, J. A., Science 2004, 303, 1644-1647. 44.  Coropceanu, V.; Comil, J.; Da Silva Filho, D. A.; Olivier, Y.; Silbey, R.; Bredas, J.-L.,  Chem. Rev. 2007, 107, 2165. 45.  Karl, N., Defect Control In Semiconductors. Elsevier: North Holland, Amsterdam, 1990;  Vol. II, p 1725-1746. 30  46.  Reddy, A. R.; Bendikov, M., Chem. Commun. 2006, 11, 1179-1181.  47.  Reichwagen, J.; Hopf, H.; Del Guerzo, A.; Desvergne, J.-P.; Bouas-Laurent, H., Org.  Lett. 2004, 6, 1899-1902. 48.  Jurchescu, 0. D.; Paistra, T. T. M., Appi. Phys. Lett, 2006, 88, 122101/1-122101/3.  49.  de Wijs, G. A.; Mattheus, C. C.; de Groot, R. A.; Paistra, T. T. M., Synth. Met. 2003,  139, 109-1 14. 50.  Bendikov, M.; Wudi, F.; Perepichka, D. F., Chem. Rev. 2004, 104, 4891-4945.  51.  Bacon, G. E.; Curry, N. A.; Wilson, S. A., Proc. Roy. Soc. (London) Ser. A 1964, 279,  98-110. 52.  Desiraju, G. R.; Gavezzotti, A., Acta Crystallogr., Sect. B: Struct. Sd. 1989, B45, 473-  482. 53.  Silinsh, E. A., Organic Molecular Crystals. Springer-Verlag: Berlin, 1980.  54.  Holmes, D.; Kumaraswamy, S.; Matzger, A. J.; Vollhardt, K. P. C., Chem. Eur. J 1999,  5, 3399-3412. 55.  Campbell, R. B.; Robertson, J. M.; Trotter, 3., Acta Cryst. 1962, 15, 289-90.  56.  Robertson, 3. M.; Sinclaire, V. C.; Trotter, 3., Acta Cryst. 1961, 14, 697-704.  57.  Hunter, C. A.; Sanders, J. K. M., I Am. Chem. Soc. 1990, 112, 5525-5534.  58.  Minakata, T.; Nagoya, I.; Ozaki, M., I Appl. Phys. 1991, 69, 7354-7356.  59.  Servet, B.; Horowitz, G.; Pies, S.; Lagorsse, 0.; Alnot, P.; Yassar, A.; Deloffre, F.;  Srivastava, P.; Hajlaoui, R.; et al., Chem. Mater. 1994, 6, 1809-1815. 60.  Gamier, F.; Yassar, A.; Hajlaoui, R.; Horowitz, G.; Deloffre, F.; Servet, B.; Ries, S.;  Alnot, P.,I Am. C’hem. Soc. 1993, 115, 8716-8721.  31  61.  Bredas, J.-L.; Calbert, J. P.; Da Silva Filho, D. A.; Comil, J., Proc. Nat!. Acaci Sci. U S.  A. 2002, 99, 5804-5809. 62.  Bredas, J.-L.; Beijonne, D.; Coropceanu, V.; Cornil, J., Chem. Rev. 2004, 104, 4971-  5003. 63.  Lemaur, V.; da Silva Filho, D. A.; Coropceanu, V.; Lehmann, M.; Geerts, Y.; Pins, J.;  Debije, M. G.; van de Craats, A. M.; Senthilkumar, K.; Siebbeles, L. D. A.; Warman, J. M.; Bredas, J.-L.; Connil, J., J Am. Chem. Soc. 2004, 126, 327 1-3279. 64.  Kwon, 0.; Coropceanu, V.; Gruhn, N. E.; Durivage, J. C.; Laquindanum, J. G.; Katz, H.  E.; Connil, J.; Bredas, J. L., I Chem. Phys. 2004, 120, 8 186-8194. 65.  Kepler, R. G., Organic Semiconductors. Macmillan: London, 1962; p 1-20.  66.  Hanada, Y.; Maruyama, Y.; Shenotani, I.; Inokuchi, H., Bull. Chem. Soc. Japan 1964, 37,  1378-13 80. 67.  Kao, K. C., Hwang, W., Electrical Transport in Solids. Pergamon Press: Willowdale,  1981; Vol. 14, p 1-64. 68.  Chou, W. Y.; Kuo, C. W.; Cheng, H. L.; Mai, Y. S.; Tang, F. C.; Lin, S. T.; Yeh, C. Y.;  Horng, J. B.; Chia, C. T.; Liao, C. C.; Shu, D. Y.,J App!. Phys. 2006, 99, 114511/1-114511/7. 69.  Goodings, E. P.; Mitchard, D. A.; Owen, G., I Chem. Soc. Perkin. Trans. 1 1972, 13 10-  13  70.  Mattheus, C. C.; de Wijs Gilles, A.; de Groot, R. A.; Paistra, T. T. M., I Am. Chem. Soc.  2003, 125, 6323-6330. 71.  Siegnist, T.; Kioc, C.; Schon, J. H.; Batlogg, B.; Haddon, R. C.; Berg, S.; Thomas, G. A.,  Angew. Chem.  mt. Ed. 2001, 40,  1732-1736.  32  72.  Mattheus, C. C.; Dros, A. B.; Baas, J.; Meetsma, A.; de Boer, J. L.; Paistra, T. T. M.,  Acta Cryst. Sect. C: Cryst. Struct. Commun. 2001, C57, 939-941. 73.  Meng, H.; Bendikov, M.; Mitchell, G.; Helgeson, R.; Wudi, F.; Bao, Z.; Siegrist, T.;  Kloc, C.; Chen, C.-H., Adv. Mater. 2003, 15, 1090-1093. 74.  Chan, S. H.; Lee, H. K.; Wang, Y. M.; Fu, N. Y.; Chen, X. M.; Cai, Z. W.; Wong, H. N.  C., Chem. Commun. 2005, (1), 66-68. 75.  Anthony, J. E.; Eaton, D. L.; Parkin, S. R., Org. Lett. 2002, 4, 15-18.  76.  Sarma, 3. A. R. P.; Desiraju, 0. R., Acc. Chem. Res. 1986, 19, 222-228.  77.  Moon, H.; Zeis, R.; Borkent, E.-J.; Besnard, C.; Lovinger Andrew, J.; Siegrist, T.; Kioc,  C.; Bao, Z., J Am. Chem. Soc. 2004, 126, 15322-15323. 78.  Podzorov, V.; Menard, E.; Borissov, A.; Kiryukhin, V.; Rogers, 3. A.; Gershenson, M.  E., Phys. Rev. Lett. 2004, 93, 086602/1-086602/4. 79.  Menard, E.; Podzorov, V.; Hur, S.-H.; Gaur, A.; Gershenson, M. E.; Rogers, J. A., Adv.  Mater. 2004, 16, 2097-2 101.  80.  da Silva Filho, D. A.; Kim, E.-G.; Bredas, J.-L., Adv. Mater. 2005, 17, 1072-1076.  81.  Miao,  Q.; Chi,  X.; Xiao, S.; Zeis, R.; Lefenfeld, M.; Siegrist, T.; Steigerwald, M. L.;  Nuckolls, C., .1 Am. Chem. Soc. 2006, 128, 1340-1345.  82.  Payne, M. M.; Odom, S. A.; Parkin, S. R.; Anthony, 3. E., Org. Lett. 2004, 6, 3325-3328.  83.  Payne, M. M.; Parkin, S. R.; Anthony, J. E.; Kuo, C.-C.; Jackson, T. N., I Am. Chem.  Soc. 2005, 127, 4986-4987. 84.  Dickey, K. C.; Anthony, J. E.; Loo, Y.-L., Adv. Mater. 2006, 18, 1721-1726.  85.  McCullough, R. D., Adv. Mater. 1998, 10, 93-116.  33  86.  Bauerle, P., Handbook of Oligo- and Polythiophenes. Wiley-VCH: Weinheim, 1999; p  88-94. 87.  Becker, R. S.; de Melo, J. S.; Macanita, A. L.; Elisei, F., I Phys. Chem. 1996, 100,  18683-18695. 88.  Bauerle, P., Handbook of Oligo- and Polythiophenes. Wiley VCH: Weinheim, 1999; p  88-135. 89.  Sato, M.; Morii, H., Polym. Commun. 1991, 32, 42-44.  90.  Sato, M.; Morii, H., Macromolecules 1991, 24, 1196-200.  91.  Chen, T.-A.; Rieke, R. D., Synth. Met. 1993, 60, 175-177.  92.  Chen, T.-A.; Wu, X.; Rieke, R. D., I Am. Chem. Soc. 1995, 117, 233-244.  93.  Sugimoto, R.; Takeda, S.; Gu, H. B.; Yoshino, K., Chem. Express 1986, 1, 635-638.  94.  Yoshino, K.; Nakajima, S.; Sugimoto, R., Jpn. I App!. Phys. 1987, 26, L1038-L1039.  95.  Kulszewicz-Bajer, I.; Pawlicka, A.; Plenkiewicz, 3.; Pron, A.; Lefrant, S., Synth. Met.  1989, 30, 335-339. 96.  Leclerc, M.; Martinez Diaz, F.; Wegner, G., Makromo!. Chem. 1989, 190, 3105-3116.  97.  Pomerantz, M.; Tseng, J. J.; Zhu, H.; Sproull, S. 3.; Reynolds, J. R.; Uitz, R.; Amott, H.  3.; Haider, M. I., Synth. Met. 1991, 41, 825-830. 98.  McCullough, R. D.; Lowe, R. D., I Chem. Soc., Chem. Commun. 1992, 70-72.  99.  Wu, X.; Chen, T.-A.; Rieke, R. D., Macromolecules 1995, 28, 2101-2102.  100.  Abdou, M. S. A.; Lu, X.; Xie, Z. W.; Orfino, F.; Deen, M. 3.; Holderoft, S., Chem.  Mater. 1995, 7, 631-641. 101.  Chen, F.; Mehta, P. 0.; Takiff L.; McCullough, R. D., I Mater. Chem. 1996, 6, 1763-  1766. 34  102.  Roncali, J., Chem. Rev. 1992, 92, 711-738.  103.  Genies, E. M.; Bidan, G.; Diaz, A. F., I Electranal. Chem. 1983, 149, 101-113.  104.  Andersson, M. R.; Thomas, 0.; Mammo, W.; Svensson, M.; Theander, M.; Inganas, 0.,  I Mater. Chem. 1999, 9, 1933-1940. 105.  Akcelrud, L., Frog. Polym. Sd. 2003, 28, 875-962.  106.  Wada, T.; Wang, L.; Okawa, H.; Masuda, T.; Tabata, M.; Wan, M.; Kakimoto, M.-A.;  Imai, Y.; Sasabe, H., Mo!. Cryst. Liq. Cryst. Sci. Tech. Mol. Cryst. Liq. Cryst. 1997, 294, 245250. 107.  Okawa, H.; Wada, T.; Sasabe, H., Mater. Res. Soc. Symp. Proc. 1992, 244, 263-268.  108.  Leclere, P.; Surin, M.; Viville, P.; Lazzaroni, R.; Kilbinger, A. F. M.; Henze, 0.; Feast,  W. J.; Cavallini, M.; Biscarini, F.; Schenning, A. P. H. J.; Meijer, E. W., Chem. Mater. 2004, 16, 4452-4466. 109.  Handbook of Conducting Polymers. Marcel Dekker: New York, 1998; p 423-467.  110.  Kingsborough, R. P.; Swager, T. M., Frog. Inorg. Chem. 1999, 48, 123-23 1.  111.  MacLachian, M. J., Frontiers in Transition Metal-Containing Polymers. John Wiley and  Sons: Hoboken, New Jersey 2007; p 161-2 17. 112.  Wolf; M. 0., Adv. Mater. 2001, 13, 545-553.  113.  Holliday, B. J.; Swager, T. M., Chem. C’ommun. 2005, 23-36.  114.  Zotti, G.; Zecchin, S.; Schiavon, G.; Berlin, A.; Pagani, G.; Canavesi, A., Chem. Mater.  1995, 7, 2309-23 15. 115.  Zotti, G.; Schiavon, G.; Zecchin, S.; Berlin, A.; Pagani, G.; Canavesi, A., Synth. Met.  1996, 76, 255-258.  35  116.  Moorlag, C.; Clot, 0.; Wolf; M. 0.; Patrick, B. 0., Chem. Commun. 2002, 24, 3028-  3 029. 117.  Moorlag, C.; Wolf; M. 0.; Bohne, C.; Patrick, B. 0., 1 Am. Chem. Soc. 2005, 127,  6382-6393. 118.  Chen, X.-Y.; Yang, X.; Holliday, B. J., I Am. Chem. Soc. 2008, 130, 1546-1547.  119.  Zhu, Y.; Millet, D. B.; Wolf; M. 0.; Rettig, S. J., Organometallics 1999, 18, 1930-1938.  120.  Leung, A. C. W.; MacLachian, M. J., I Inorg. Organomet. Polym. Mater. 2007, 17, 57-  89. 121.  Horwitz, C. P.; Murray, R. W., Mol. Cryst. Liq. Cryst. 1988, 160, 389-404.  122.  Goldsby, K. A.; Blaho, 3. K.; Hoferkamp, L. A., Polyhedron 1989, 8, 113-115.  123.  Dahm, C. E.; Peters, D. G.,Anal. Chem. 1994, 66, 3117-3123.  124.  Dahm, C. E.; Peters, D. G., I Elecfroanal. Chem. 1996, 406, 119-129.  125.  Miomandre, F.; Audebert, P.; Maumy, M.; Uhi, L., I Electroanal. Chem. 2001, 516, 66-  72. 126.  Okada, T.; Katou, K.; Hirose, T.; Yuasa, M.; Sekine, I., Chem. Lett. 1998, 8, 841-842.  127.  Reddinger, J. L.; Reynolds, 3. R., Synth. Met. 1997, 84, 225-226.  128.  Reddinger, J. L.; Reynolds, J. R., Macromolecules 1997, 30, 673-675.  129.  Reddinger, 3. L.; Reynolds, J. R., Chem. Mater. 1998, 10, 1236-1243.  130.  Reddinger, 3. L.; Reynolds, J. R., Chem. Mater. 1998, 10, 3-5,  131.  Kingsborough, R. P.; Swager, T. M., I Am. C’hem. Soc. 1999, 121, 8825-8834.  132.  Kingsborough, R. P.; Swager, T. M., Chem. Mater. 2000, 12, 872-874.  133.  Shioya, T.; Swager, T. M., Chem. Commun. 2002, 13, 1364-1365.  36  CHAPTER 2 Synthesis and Characterization of Novel Luminescent Bent Acenedithiophenes*  2.1  INTRODUCTION  Thiophene-containing oligoacenes are studied extensively for their semiconducting properties and applications in organic field effect transistors (OFETs).’’ 2 The appeal relative to their allcarbon analogs is due in part to the site-selective reactivity that is inherent in the thiophene ’ 9 moieties.  13  This has led to the development of new derivatized materials with improved  solubility, environmental stability, processability, and device performance. Chart 2-1 shows a variety of thiophene containing oligoacenes (48-54) that have been recently investigated (see references 1-12). These rigid it-conjugated molecules are structurally analogous to anthracene, tetracene, pentacene, and hexacene. In the work presented in this Chapter, motivation was provided by the hypothesis that molecules based on a bent acenedithiophene (67) that is structurally analogous to dibenz{a,h]anthracene, a structural isomer of pentacene, may also be of interest for organic electronics applications. Bent anthradithiophenes (BADTs) are virtually 14 and there is no reported route to the parent unsubstituted compound. Swager and unexplored  A version of this chapter has been published. Pietrangelo, A.; MacLachian, M.J.; Wolf M.O.; Patrick, B.O. Org. Lett. 2007, 9, 357 1-3573.  37  co-workers have developed aryl-functionalized derivatives using a chemical cyclization strategy; however, this is limited in scope. ’ 15  16  Chart 2-1  48  49  51  52  QsO (0) S 5 1 3  In this Chapter, a new route to luminescent BADTs using an oxidative photocyclization-based synthetic strategy is reported. The synthesis and spectroscopy of BADTs 67-71 (see Scheme 2-I) and their thiophene-phenylene oligomer precursors are discussed in detail. This route enables access to dialkyl- and diphenyl-functionalized BADTs with the substituents modifying both the solubility and packing structure in the solid state (see Chapter 3). In addition, the major product prepared by the oxidative photocyclization of the novel cis,cis- and trans,trans-2,5dithienyl-1 ,4-distyrylbenzenes is discussed.  38  2=2 2.2.1  EXPERIMENTAL General  Materials and Equipment. Chromium trioxide, 2-tributyistannyithiophene, anhydrous dimethylformamide (DMF), p-xylene, methyltriphenyiphosphonium bromide, and benzyl triphenyiphosphonium chloride were purchased from Aldrich. Tetrakis(triphenylphosphine) palladium(0) was purchased from Strem. Tetrahydrofuran (THF) was distilled from sodium and benzophenone under nitrogen gas. Deuterated solvents were purchased from Cambridge Isotope Laboratories, Inc. All purchased chemicals were used without further purification. 2,5Dibromobenzene,  ‘7  2,5-dibromoterephthalaldehyde,  18  9 5-methyl-2-tributylstannylthiophene,’  ° 5-dodecyl-2-tributylstannylthiophene, 2 5-hexyl-2-tributylstannylthiophene, ’ and 5-phenyl-22 22 were prepared according to literature procedures. All reactions were tributylstannylthiophene carried out under a dinitrogen atmosphere unless otherwise noted. All photochemical reactions were carried out in a Rayonet Photoreactor (Southern New England Ultraviolet Company, Branford, CT) equipped with 16 RPR-3000  A (300 nm, 21 W) lamps. ‘H NMR spectra were  recorded on either a Bruker AV-300 or AV-400 spectrometer and calibrated to the residual protonated solvent at  5.32 for deuterated dichloromethane 2 CI and (CD )  7.24 for deuterated  chloroform (CDC1 ) All ‘ 3 C NMR experiments were carried out in 2 3 CI and calibrated at CD 54.00. Solution absorption spectra were obtained in dichloromethane (DCM, 2 C1 on a CJ-1 ) Vàrian Cary 5000 UV-vis-near-IR spectrophotometer using a 1 cm quartz cuvette. JR spectra were obtained directly from samples using a Nicolet 6700 FT-JR spectrometer or from KBr dispersions on a Bomem MB-100 FT-JR spectrometer. Fluorescence spectra were obtained in DCM on a Photon Technology International QuantaMaster fluorimeter using a 1 cm quartz  39  cuvette. Quantum yields were referenced to a solution of anthracene in EtOH. ( r 1  =  O.3).23  Melting points were obtained on a Fisher-Johns melting point apparatus. Electron ionization EI) mass spectra were obtained at the UBC Mass Spectrometry facility. Elemental analyses were obtained at the UI3C Microanalytical facility. Scanning electron microscopy (SEM) images were taken using a Hitachi S4700 electron microscope operating at 5 kV. Electrodeposited films were imaged on Au/Si electrodes. DFT calculations on 68 were performed using a B3LYP/6-3 IG* basis set implemented in the Spartan 02 software package. X-ray Crystallographic Analysis. Suitable single crystals of 58 and 74 were grown from cold DCM and mounted on glass fibres and the data collected at 173(1) K on a Bruker X8 APEX II  diffractometer with graphite monochromated Mo-Kc radiation. Data were collected in a series of 4) and co scans in 0.5& oscillations with 10.0 second exposures, and collected and integrated using the Bruker SAINT software package. 24 Data were corrected for absorption effects using 25 and corrected for Lorentz and polarization effects. The the multi-scan technique (SADABS)  structure was solved using direct methods 26 and refined using the SHELXTL crystallographic software package of Bruker-AXS. 27 The structures were obtained at UBC by Dr. Brian Patrick. See Appendix 1 for tabulated data. Electrochemistry. Cyclic voltammetry experiments were conducted using an Autolab potentiostat. The working electrode was either a Pt disk, an indium tin oxide (ITO) thin film on glass, or a wafer comprised of Au (1000  A) deposited on Si using a Cr (50 A) adhesion layer.  The counter electrode was a Pt mesh and the reference electrode a silver wire. An internal reference, decamethylferrocene, was added to correct the measured potentials with respect to saturated calomel electrode (SCE). Anhydrous 4 NJC1O was purchased from Aldrich and [(n-Bu)  40  used as is. All experiments were carried out using a scan rate of 100 mV/s. DCM used for CV experiments was purified by passing the solvent through an activated alumina tower. 2.2.2  Synthesis  2,5-di(2-thienyl)terephthalaldehyde (57). A 100 mL round bottom Schienk flask was charged with  2,5-dibromoterephthalaldehyde  56  (2.00  g,  mmol),  6.85  tetrakis(triphenylphosphine)palladium(0) (800 mg, 0.692 mmol), 2-tributyistannyithiophene (7.68 g, 20.6 mmol) and anhydrous DMF (60 mL) and heated to 80°C with stirring for 72h. The reaction mixture was then cooled to room temperature, diluted with Et 0, and filtered through 2 Celite. The organic phase was washed with brine and water and dried over MgSO . After 4 filtration, the solvent was removed to yield the crude product that was then chromatographed on silica using a hexanelDCM (2:1) solvent mixture as the eluent (Rf= 0.29). The desired product was obtained as a crystalline yellow solid (1.35 g, yield 66%). ‘H NMR 2 CI 300 MHz) (CD , 10.25 (2H, s, CHO), 8.12 (2H, s, aromatic Cl]), 7.57 (2H, dd,  JHH 3  =  4.97 Hz,  Jmi 3  =  1.28 Hz,  aromatic Cl]), 7.19 (4H, m, aromatic CR). ‘ C NMR 2 3 CI 100 MHz) ö 191.6, 138.0, 137.5, (CD , 137.4, 131.3, 130.7, 128.8, 128.6. EI-MS:  m/z  =  298 (M, 100%). UV-vis 2 C: (CH ) I  374 (4600), 269 (29600) nm (L mol’cm’). JR (KBr): v  =  Xmax (E)  =  1684, 1529, 1431, 1384, 1327, 1279,  1144, 846, 818, 721 cm . Mp. 160-162 °C. Anal. Calcd for 0 1 H, C, 64.41; H, 3.38. 6 C, : S 2 Found: C, 64.61, H, 3.42. cI  0.39.  2,5-di(5-methyl-2-thienyl)terephthalaldehyde (58). The same procedure was used as for preparation of 57. Rf  =  0.38 (hexane/DCM (2:1)). The product was isolated as an orange  crystalline solid (yield 72%). ‘H NMR 2 C1 400 MHz) 6 10.25 (2H, s, CHO), 8.05 (2H, s, (CD , aromatic Cl]), 6.94 (2H, d,  JIiH 3  =  3.46 Hz, aromatic CR), 6.86 (2H, m, aromatic CR), 2.57 (6H, 41  C1 100 MHz) 6 191.8, 144.0, 137.4, 137.2, 135.6, 131.0, 130.7, 127.0, (CD , ). ‘C NMR 2 3 s, Cl-I 15.7. EI-MS: m/z  =  326.1 (M, 100%). UV-vis ) CL 2 (CH :  271 (24700) nm (L moF’cm). JR (KBr): v  =  ()  =  401 (5600), 308 (17800),  1684, 1560, 1460, 1399, 1278, 1146, 912, 824,  . Mp. 164-166 °C. Anal. Calcd for 2 1 796, 720 cm 0 C 1 H : S 8 C, 66.23; H, 4.32. Found: C, 4  66.64; H, 4.32.  =  0.85.  2,5-di(5-hexyl-2-thienyl)terephthalaldehyde (59). The same procedure was used as for preparation of 57. Rf  =  0.58 (hexane/DCM (2:1)). The product was isolated as a yellow  crystalline solid (yield 87%). ‘H NMR 2 C1 400 MHz) 6 10.26 (2H, s, CHO), 8.06 (2H, s, (CD , aromatic CR), 6.95 (2H, d,  JHJ{ 3  =  3.50 Hz, aromatic CR), 6.87 (2H, d, 11 = 3.50 Hz, aromatic J 3 1  ), 1.69-1.77 (4H, m, CH 2 ), 1.45-1.32 (12H, m, CH 2 ), 0.91 2 CH), 2.88 (4H, t, 3 Jrn = 7.60 Hz, Cl-I  (6H, t,  J,*i 3  =  6.99 Hz, CH ). ‘ 3 C NMR 2 3 C1 100 MHz) 6 191.9, 150.2, 137.4, 137.2, 135.4, (CD ,  131.0, 130.5, 125.8, 32.2, 32.1, 30.7, 29.4, 23.2, 14.4. EI-MS: m/z C: 2 (CH ) 1  ()  =  466 (M, 100%). UV-vis  403 (5500), 311(18800), 272 (23500) nm (L mor’cm). IR (KBr): v  =  2953, 2924, 2853, 1683, 1490, 1465, 1465, 1395, 1382, 1282, 1256, 1151, 1053, 905, 818 cm. 24 C 3 H : S 2 8 C, 72.06; H, 7.34. Found: C, 72.38; H, 7.42. t= 0.92. Mp. 90 C. Anal. Calcd for 0 2,5.-bis(5-dodecyl-2-thienyl)terephthalaldehyde (60). The same procedure was used as for preparation of 57. Rf  0.69 (hexane/DCM (2:1)). The product was recrystallized in hexanes and  isolated as a yellow crystalline solid (yield 46%). ‘H NMR 2 C1 400 MHz) 6 10.26 (2H, s, (CD , CHO), 8.06 (2H, s, aromatic CR), 6.95 (2H, d, 3 J 3.45 Hz, aromatic CR), 2.88 (4H, t, 3 J  ), 0.88 (6H, t, 2 (36H, m, CH  JHH  =  =  3.48 Hz, aromatic CR), 6.87 (2H, d,  J}TJ{ 3  7.54 Hz, CH ), 1.77-1.69 (4H, m, CH 2 ), 1.41-1.28 2  6.53 Hz, CH ). 13 3 CI 100 MHz) 6 191.9, 150.2, (CD , C NMR 2  137.5, 137.2, 135.4, 130.9, 130.5, 125.8, 32.5, 32.3, 30.7, 30.24, 30.22, 30.13, 29.93, 29.90,  42  29.68, 23.3, 14.5. EI-MS: m/z  =  634 (M, 100%). UV-vis 2 C: (CH ) 1  (8)  =  403 (5400), 311  (18000), 272 (22400) nm (L moF’cm’). JR (KBr): v 2918, 2850, 1684, 1491, 1471, 1382, 1285, 1154, 1096, 905, 817 cm’ . Mp. 97-98 °C. Anal. Calcd for 0 1 48 C 5 H : S 2 0 C, 75.66; H, 9.21. Found: C, 75.70, H, 9.23. I= 0.89. 2,5-bis(5-phenyl-2-thienyl)terephthalaldehyde (61). The same procedure was used as for preparation of 57. Rf = 0.70 2 CI (1:1)). The product was recrystallised in DCM and (hexane/CH isolated as an orange solid (yield 43%). ‘H NMR 2 CI 400 MHz) ö 10.36 (2H, s, CHO), (CD , 8.19 (2H, s, aromatic Cl]), 7.70 (4H, m, aromatic CH), 7.44 (6H, m, aromatic CH), 7.36 (2H, t, JHH  =  7.39 Hz, aromatic CH), 7.16 (2H, d, 3 111 J  3.72 Hz). ‘ C NMR 2 3 C1 100 MHz) ö (CD ,  191.5, 148.0, 137.42, 137.26, 134.2, 131.29, 131.26, 129.7, 128.8, 126.4, 124.7. EI-MS: m/z 450 (M, 100%). UV-vis 2 C: (CH ) I mo[’cm’). IR: v  (6)  =  =  270 (22400), 333 (29300), 413 (11400) nm (L  1681, 1476, 1444, 1379, 1325, 1270, 1251, 1146, 1079, 903, 822, 812, 759,  689, 644, 634, 586, 553, 532 cm . Mp > 230 °C. Anal. Calcd for H, 1 28 C, 74.64; H, 4.03. C : S 2 0 8 Found: C, 74.24; H, 4.04. cI = 0.83. 2,5-bis(2-thienyl)-1,4-diviuylbenzene (62). A suspension of methyltriphenylphosphonium bromide (1.15 g, 3.22 mmol) and 60 mL of anhydrous TI-IF in a 250 mL round bottom Schienk flask was cooled to 0 °C and left to stir for 30mm. With stirring, 1.84 mL of n-BuLi (1.6 M in hexanes) was added dropwise. After an additional 30mm  of stirring, a solution of 2,5-di(2-  thienyl)terephthalaldehyde 57 (400 mg, 1.34 mmol) dissolved in 30 mL of anhydrous TI-IF was added. The combined solution was then warmed to room temperature and left to stir for 24h. Solvent was then removed under reduced pressure and the product purified by column chromatography using DCM as the eluent (Rf  =  1.00). The product was isolated as a white  43  crystalline solid (324 mg, yield 82%). ‘H NMR (CDC1 , 300 MHz) 6 7.64 (2H, s, aromatic CR), 3 7.36 (2H, dd,  .JFJJI 3  (2H, dd, 3 Jjnj  =  =  3.85 Hz, 11 J,3  17.47 Hz, 3 1 J  =  =  2.49 Hz, aromatic CR), 7.10 (4H, m, aromatic CR), 6.94  10.97 Hz, vinylic CR) 5.73 (2H, dd, 3 1 J  1.19 Hz, vinylic CR), 5.27 (2H, dd, 3 Jin  =  10.98, 1 -,jJ 2  =  =  17.46 Hz, 2 1 J  =  1.18 Hz, vinylic CR). ‘ C N1VIR 3  C1 100 MHz) 6 142.0, 136.4, 135.7, 133.3, 128.9, 128.4, 127.9, 126.5, 116.4. EI-MS: m/z (CD , 2 =  294 (M, 100%). UV-vis 2 C: (CH ) 1 2 (e)  =  276 (33200) nm (L mor’cm ). IR (KBr): v 1  =  2924, 2855, 1419, 1232, 1211, 1042, 985, 915, 898, 851, 836, 707, 699 cm . Mp. 108-110 °C. 1 Anal. Calcd for S C 1 H : 2 8 C, 73.43; H, 4.79. Found: C, 73.67, H, 5.10. 4 2,5-di(5-methyl-2-thienyl)-1,4-divinylbenzene (63). The same procedure was used as for preparation of 62. Rf = 1.00 (DCM). The product was isolated as a white solid (yield 76%). 1 H NIVIR 2 C1 400 MHz) 6 7.61 (2H, s, aromatic CR), 7.00 (2H, dd, (CD ,  JHJ{ 3  =  17.47 Hz, 3 J,ni  10.98 Hz, vinylic CR), 6.90 (2H, d, 3 , = 3.45 Hz, aromatic CR), 6.78 (2H, dd, 1 J =  1.07 Hz, aromatic CR), 5.74 (2H, dd, 3 J,nj  (2H, dd,  J1-iH 3  =  10.96,  J,iH 2  =  17.45 Hz,  JHH  =  =  =  3.43 Hz,  1.19 Hz, vinylic CR), 5.28  1.17 Hz, vinylic CR), 2.53 (6H, s, CH ). ‘ 3 C NMR 2 3 C1 100 (CD ,  MHz) 6 141.3, 139.7, 136.1, 135.9, 133.3, 128.7, 128.25, 126.2, 116.0, 15.6. EI-MS: m/z  =  322.1 (M, 100%). JJV-vis 2 C: (CH ) 1 Xm  =  (6)  =  279 (23600) nm (L moF’cm’). JR (KBr): v  2924, 2855, 1376, 1260, 1240, 1212, 1093, 1060, 993, 897, 803, 794, 617 cm . Mp. 115-117 1 °C. Anal. Calcd for H, 20 C, 74.49; H, 5.63. Found: C, 74.33; H, 5.55. C : 2 S 3 2,5-di(5-hexyl-2-thienyl)-1,4-divinylbenzene (64). The same procedure was used as for preparation of 62. Rf  =  0.96 (DCMlhexanes (1:1)). The product was isolated as a white solid  (yield 74%). ‘H NMR 2 C1 400 MHz) 6 7.61 (2H, s, aromatic CR), 7.01 (2H, dd, (CD , 17.47 Hz, 3 Jp- = 10.98 Hz, vinylic CR), 6.91 (2H, d,  -JJ{ 1 J 3  =  =  3.48 Hz, aromatic CR), 6.79 (2H, d,  44  =  3.48 Hz, aromatic CH), 5.74 (2H, dd, 3 J,  (2H, dd, 3 J,, = 10.97,  =  =  17.44 Hz, 2 J  1.11 Hz, vinylic H), 5.28  =  7.63 Hz, CH ), 1.76-1.68 2  1.13 F{z, vinylic CR), 2.85 (4H, t,  ), 1.5 1-1.32 (12H, m, CH 2 (4H, m, CH ), 0.89 (6H, t, 3 2 J  100 Tvll-Iz)  =  =  6.98 Hz, CH ). ‘ 3 C NMR 2 3 C1 (CD ,  147.5, 139.4, 136.1, 136.0, 133.4, 128.7, 128.0, 124.9, 116.0, 32.3, 32.2, 30.7, 29.4,  23.2, 14.4. EI-MS: m/z  =  462.2 (M, 100%). UV-vis ) C: 2 (CH 1  mol’cm’). IR (KBr): v  =  2958, 2925, 2849, 1493, 1473, 1271, 1055, 1038, 996, 957, 913, 903,  (s)  =  280 (30900) nm (L  . Mp. 50 C. Anal. Calcd for S 1 801, 607, 517 cm C 3 H : 2 0 C, 77.86; H, 8.28. Found: C, 77.65; H, 8 8.33. 2,5-bis(5-dodecyl-2-thienyl)-1,4-divinylbenzene (65). The same procedure was used as for preparation of 62. Rf = 0.96 (hexane/CH C1 (1:1)). The product was isolated as a white solid 2 C1 400 MHz) ö 7.61 (2H, s, aromatic CR), 7.01 (2H, dd, 3 (CD , (yield 80%). ‘H NMR 2 J-,  =  17.44 Hz, 3 J,nj = 10.98 Hz, vinylic CR), 6.91 (2H, d, 3 JHIj = 3.46 Hz, aromatic CR), 6.79 (2H, d, 3.44 Hz, aromatic CR), 5.74 (2H, d, 11.04, vinylic CR), 2.84 (4H, t, m, CH ), 0.88 (6H, t, 11 2 J, 3  =  J}U-{ 3  =  JF{J{ 3  =  17.44 Hz, vinylic CR), 5.28 (2H, d, 3 J  =  7.52 Hz, CH ), 1.41-1.27 (36H, 2 ), 1.75-1.68 (4H, m, CH 2  6.30 Hz, CH ). ‘ 3 C1 100 MHz) 8 147.5, 139.3, (CD , C NMR 2 3  136.1, 133.4, 128.7, 128.0, 124.9, 116.0, 32.5, 32.4, 30.7, 30.3, 30.2, 30.1, 29.9, 29.7, 23.3, 14.4. EI-MS: m/z cm’). IR (KBr): v  =  =  630.4 (M, 100%). UV-vis ) C: 2 (CH I  ?‘.m (6)  =  280 (31600) nm (L moF’  2960, 2916, 2849, 1497, 1472, 1465, 1058, 1005, 960, 907, 898, 808, 718,  . Mp. 81 °C. Anal. Calcd for S 1 605, 523 cm 42 C, 79.94; H, 9.90. Found: C, 79.88; H, C 6 H : 2 10.08.  45  2,5-bis(5-phenyl-2-thienyl)-1,4-divinylbenzene (66). The same procedure was used as for  preparation of 62. Rf = 1.00 (DCM). The product was isolated as a white solid (yield 84%). ‘H NMR 2 C1 400 IVIHz) ö 7.74 (2H, s, aromatic CR), 7.67 (4H, d, (CD , CR), 7.42 (4H, t, J 3 ,j = 7.44 Hz, aromatic CR), 7.36 (2H, d, 3 J (2H, t, 3 J, =  (2H, d,  =  =  7.40 Hz, aromatic  3.67 Hz, aromatic CR), 7.32  7.37 Hz, aromatic CR), 7.13 (2H, d, 3 Jij = 3.67 Hz, aromatic CR), 7.08 (2H, dd,  17.47 Hz, j, 3 1  JHJ{ 3  =  JfJ 3 { 1  =  11.03 Hz, vinylic CR), 5.82 (2H, d, 3 J  17.42 Hz, vinylic CR), 5.35  11.53 Hz, vinylic CR). 13 C NMR 2 C1 100 MHz) (CD ,  145.4, 141.5, 136.4,  135.8, 134.7, 133.2, 129.54, 129.49, 128.88, 128.23, 126.2, 124.0, 116.6. EI-MS: m/z (M, 100%). UV-vis 2 C: (CH ) 1 =  2max  =  446.1  ). IR: v 1 () 344 nm (25300), 291 nm (20400) (L mor’cm =  1592, 1485, 1460, 1444, 1408, 1379, 1337, 1254, 1159, 1099, 1075, 982, 940, 920, 897, 889,  842, 812, 753, 686, 615 cm . Mp. 209 °C. Anal. Calcd for S 1 32 C 2 H : 2 0 C, 80.68; H, 4.96. Found: C, 80.41; H, 5.07. Authra(1,2-b: 5,6-b’)dithiophene (67). A 500 mL quartz flask was charged with 2,5-bis(2-  thienyl)-1,4-divinylbenzene 62 (90 mg, 0.31 mmol), iodine (154 mg, 0.61 mmol), and 300 mL of benzene sparged with dinitrogen gas. The flask was irradiated with IJV light while the progress of the reaction was monitored by UV-vis absorption spectroscopy. Once complete, the organic solution was first washed with an aqueous sodium thiosulfate solution, then water, and dried over 4 SO After filtration, the solvent was removed under reduced pressure to yield a 2 Na . dark brown solid that was chromatographed on silica using a hexanelDCM (1:1) (Rf  0.64)  mixture as the eluent. The product was isolated as a yellow solid and recrystallized in 2 C1 at CH —10 °C (36 mg, 40%). ‘H NMR 2 C1 400 MHz) 6 8.76 (2H, s, aromatic CR), 7.94 (2H, d, (CD , HH 1  =  8.82 Hz, aromatic CR), 7.87 (2H, d,  5.22 Hz, aromatic CR), 7.53 (2H, d, 3 J  JH}{ 3  =  8.80 Hz, aromatic CR), 7.60 (2H, d, 3 J,-n  =  5.22 Hz, aromatic R). ‘ C NMR 2 3 C1 100 MHz) (CD , 46  o  137.6, 137.6, 130.5, 127.8, 126.1, 125.9, 125.7, 123.1, 123.1. EI-MS:  UV-vis ) C: 2 (CH I  max (6)  =  m/z  =  290 (M, 100%).  304 (142900), 292 (60000) nm (L 1 mor’cm ) . IR (KBr): v  2923,  2855, 1279, 1145, 1083, 883, 839, 782, 693, 601 cm’. Mp. 223-225 °C. Anal. Calcd for  18 C, 74.45; H, 3.47. Found: C, 74.80, H, 3.82. cI 0.36. C : 2 S 0 H, Anthra(1,2-b: 5,6-b’)di-5-methylthiophene (68). The same procedure was used as for preparation of 67. Rf  =  0.64 (hexane/DCM (1:1)). The product was isolated as a yellow solid  C1 at —10 C (yield 37%). 1 CH and recrystallized in 2 C1 400 MHz) 6 8.59 (2H, s, (CD , H NMR 2 aromatic CR), 7.86 (2H, d, 3 J = 8.77 Hz, aromatic CR), 7.72 (2H, d, 3 Jinj = 8.78 Hz, aromatic C1 100 MHz) 6 140.6, 2 (CD CR), 7.17 (2H, s, aromatic CR), 2.70 (6H, s, 3 CH ) . 3 ‘ NMR , C 137.9, 136.5, 130.2, 127.4, 125.6, 124.1, 122.7, 122.6, 16.4. EI-MS:  UV-vis ) C: 2 (CH I2  318 (M, 100%).  m/z  () 309 (217900), 296 (96300) nm (L mo[’cm’). JR (KBr): v 2921, =  =  2850, 1458, 1269, 1201, 1091, 983, 869, 829, 801, 699, 670, 606, 490 cm . Mp. >230 °C. 1  cf  0.56.  Anthra(1,2-b: 5,6-b’)di-5-hexylthiophene (69). The same procedure was used as for preparation of 67. Rf  =  0.80 (hexane/DCM (1:1)). The product was isolated as a yellow solid  and recrystallized in chloroform (CHCI ) at —10 °C (yield 62%). ‘H NMR 2 3 C1 400 MHz) 6 (CD , 8.60 (2H, s, aromatic CR), 7.86 (2H, d, 3 J  =  8.80 Hz, aromatic CR), 7.72 (2H, d, 3 J,  =  8.80  Hz, aromatic CR), 7.18 (2H, s, aromatic CR), 3.01 (4H, t, J3 ), 1.90-1.78 (4H, 2 mj-, = 7.49 Hz, CH ), 0.91 (6H, t, 2 m, CH ), 1.47-1.27 (12H, m, CH 2  JHJ 3  =  ). ‘ 3 C NMR 2 3 C1 100 (CD , 6.93 Hz, CH  MHz) 6 146.7, 137.6, 136.1, 130.1, 127.4, 125.6, 122.9, 122.7, 122.6, 32.2, 32.1, 31.3, 29.4, 23.2, and 14.4. EI-MS:  m/z  =  458 (M, 100%). UV-vis ) C: 2 (CH I  (52900) nm (L mor’cm’). JR (KBr): v  =  )max  ()  =  311(129500), 298  2953, 2926, 2849, 1466, 1092, 984, 872, 832, 794,  47  724, 699, 670, 607, 491, 458 cm . Mp. 117-119 ‘C. Anal. Calcd for S 1 C 3 H : 2 0 C, 78.55; H, 4 7.47. Found: C, 78.28; H, 7.77. I= 0.60. Anthra(1,2-b: 5,6-b’)di-5-dodecylthiophene (70). The same procedure was used as for  preparation of 67. Rf  =  0.88 (hexane/DCM (1:1)). The product was isolated as a yellow solid  and recrystallized in CHC1 3 at —10 °C (yield 56%). ‘H NMR 2 C1 400 MHz) ö 8.61 (2H, s, (CD , aromatic CR), 7.86 (2H, d,  JHj1 3  =  8.77 Hz, aromatic CR), 7.73 (2H, d, 1 J,-, = 8.79 Hz, aromatic 3  CR), 7.19 (2H, s, aromatic CR), 3.01 (4H, t, 3 J, 1.50-1.27 (36H, m, CH ), 0.88 (6H, t, 3 2 Jim  7.49 Hz, CH ), 1.87-1.80 (4H, m CH 2 ), 2  6.93 Hz, CH ). ‘ 3 C NMR 2 3 C1 100 MHz) ö (CD ,  146.7, 137.7, 136.2, 130.2, 127.5, 125.6, 122.9, 122.8, 122.6, 32.5, 32.2, 31.3, 30.3, 30.2, 30.1, 30.0, 29.9, 29.7, 23.3, 14.5. EI-MS: m/z  =  626 (M, 100%). UV-vis ) C: 2 (CH 1  (162000), 298 (67000) nm (L mol’cm’). JR (KBr): v  =  2max (8)  311  2954, 2922, 2851, 1469, 1094, 984,  871, 826, 793, 720, 699, 606 cm’. Mp. 123-125 ‘C. Anal. Calcd for S 48 C 5 H : 2 2 C, 80.45; H, 9.32. Found: C, 80.10; H, 9.52.  =  0.66.  Anthra(1,2-b: 5,6-b’)di-5-phenylthiophene (71).  The same procedure was used as for  preparation of 67 with the following modifications. The photolysis reaction was carried out in  xylenes sparged with dinitrogen gas. After the reaction was complete, the organic solution was washed with aqueous sodium thiosulfate solution, then water, and dried over 4 SO After 2 Na . filtration, the solvent was removed under reduced pressure to yield an insoluble brown solid that was purified by multiple rinsing with DCM followed by sublimation. The fmal product was isolated as a yellow solid (yield 37%). ‘H NMR (DMSO-d , 400 MHz) 6 8.89 (2H, s, aromatic 6 CR), 8.13 (2H, d, 3 J = 8.74 Hz, aromatic CR), 8.08 (2H, s, aromatic, CR), 7.95 (2H, d, 8.73 Hz, aromatic CR), 7.89 (4H, d,  =  7.46 Hz, aromatic CR), 7.54 (4H, t,  JFTJI 3  JHH 3  =  7.50 Hz,  48  aromatic Cl]), 7.43 (2H, t, 3 Ji vis ) C: 2 (CH I  )‘max  (s)  =  =  7.24 Hz, aromatic Cl]). EI-MS: m/z  442 (M, 100%). UV  324 (89400), 339 (156200), 400 (17500) nm (L mor’cm’). IR: v  1071, 1025, 879, 835, 801, 757, 745, 689, 608 cm. Mp  Cis,cis-2,5-bis(2-thienyl)-1,4-distyrylbenzene  >  =  230 C.  (72).  A  suspension  of  benzyltriphenylphosphonium chloride (313 g, 0.805 mmol) and 30 mL of anhydrous THF in a 250 mL round bottom Schlenk flask was cooled to 0 °C and left to stir for 30mm. With stirring, 0.46 mL of n-BuLi (1.6 M in hexanes) was added dropwise. After an additional 30 mm of stirring, a solution of 2,5-di(2-thienyl)terephthalaldehyde 57 (100 mg, 0.335 mmol) dissolved in 30 mL of anhydrous THF was added. The combined solution was then warmed to room temperature and left to stir for 24h. Solvent was then removed under reduced pressure and the product purified by column chromatography using DCM as the eluent (Rt- = 0.97). The cis,cis isomer was isolated as a white solid (120 mg, yield 80 %). ‘H NMR 2 C1 400 MHz) (CD , (2H, s, aromatic Cl]), 7.30 (12H, m, aromatic Cl]), 7.05 (2H, d, 3 J 7.00 (2H, dd, 3 JFm  =  5.02 Hz, 3 Jnj  =  =  7.43  3.55 Hz, aromatic Cl]),  3.67 Hz, aromatic Cl]), 6.71 (2H, d, 3 Jjm  =  12.09 Hz,  olefinic Cl]), 6.67 (2H, d, J3 C1 100 MHz) ö 142.4, (CD , C NMR 2 3 ,-m = 12.09 Hz, olefinic Cl]). ‘  137.5, 135.2, 133.0, 132.2, 132.1, 130.2, 129.5, 128.8, 127.86, 127.83, 127.6, 126.5. EI-MS: m/z =  446 (M, 100%). UV-vis ) C: 2 (CH I  2max  (s)  =  311 nm (27400) (L mol’cm’). IR: v  =  1481,  1438, 1400, 1382, 1241, 1241, 1213, 1072, 1056, 919, 904, 846, 831, 773, 744, 735, 690, 538, . Mp. 175-177 C. Anal. Calcd for S 1 505, 471, 445 cm 32 C 2 H : 2 0 C, 80.68; H, 4.96. Found: C, 80.79, H, 5.17.  49  Trans,trans-2,5-bis(2-thienyl)-1,4-distyrylbenzene (73). Compound 72 was converted to the trans,trans-isomer by refluxing in 10 mL of xylenes containing a catalytic amount of ‘2 for 12 h. After cooling, the product was precipitated by the addition of methanol and isolated on a BUchner funnel (100 mg, 83%). 1 H NMR 2 C1 400 MHz) 6 7.85 (2H, s, aromatic CH), 7.47 (CD , (6H, m, aromatic CR), 7.40 (2H, d, 7.22 (2H, dd, =  JHJT 3  =  3.51 Hz, 3 111 J  J}IH 3  =  16.24 Hz, olefinic CR), 7.35 (4H, m, aromatic CR),  1.17 Hz, aromatic CR), 7.18 (2H, dd,  3.57 Hz, aromatic CR), 7.14 (2H, d,  JHJ{ 3  =  JjTji 3  5.06 Hz,  J}Tj-f 3  16.23 Hz, olefinic H). ‘ C NMR 2 3 C1 100 (CD ,  MI-Tz) 6 142.3, 138.0, 135.8, 133.8, 131.1, 129.3, 129.0, 128.44, 128.33, 128.07, 127.29, 127.21, 126.8. EI-MS: m/z  =  446 (M, 100%). UV-vis 2 C: (CH ) 1  )m  (s)  =  312 (43600), 348 (43700)  nm (L mor’ cm’). IR: v = 1594, 1493, 1446, 1390, 1315, 1235, 1207, 983, 946, 897, 854, 840, 755, 710, 731, 689, 669, 590, 513, 484 cm . Mp. >220 °C. Anal. Calcd for S 1 32 C 2 H : 2 0 C, 80.68; H, 4.96. Found: C, 80.31; H, 5.30. Helicene (74). The same procedure was used as for preparation of 67 with the following  modifications. After purification by flash column chromatography, side products of lower solubility that eluted with the helicene were separated by precipitation from cold hexane/DCM (1:1) solutions. The final product is a grey solid (yield 20%) that decomposes in solution at room temperature. Rf 0.80 (hexane/DCM (1:1)). 2 CI 400 MHz) 68.85 (1H, d, ‘HNMR(CD , J.n.i 3  =  8.44 Hz, aromatic CR), 8.20 (1H, d, 3 Jin,  CR), 8.05 (IH, d,  =  =  8.84 Hz, aromatic CR), 8.10 (1H, s, aromatic  7.85, aromatic CR) 7.95 (2H, m, aromatic CR), 7.78 (2H, d, 3 Jini  6.94 Hz, aromatic CR), 7.68  (  1H, t, , 141 J 3  =  6.91 Hz, aromatic CR), 7.58 (2H, t, 3 Jmi  aromatic CR), 7.50 (4H, m, aromatic CR), 7.35 (1H, d, 3 J,, dd,  JHH 3  =  3.49 Hz, 3 J4j  =  =  7.24 Hz,  5.57 Hz, aromatic CR), 7.32 (IH,  1.17 Hz, aromatic CR), 7.25 (1H, dd,  JHJ{ 3  5.15 Hz, 3 Jjnj  3.50 Hz,  aromatic CR). ‘ C NMR 2 3 C1 100 MHz) 6 141.8, 141.0, 139.3, 139.1, 137.9, 133.2, 131.42, (CD , 50  131.37, 130.76, 130.72, 130.3, 129.9, 129.2, 128.82, 128.67, 128.33, 128.23, 128.05, 128.01, 127.9, 127.7, 126.6, 125.43, 125.36, 125.03, 124.83, 124.15, 123.89. EI-MS: m/z 100%). UV-vis ) C: 2 (CH 1 IR: v  =  (E)  =  442 (M,  319 (33917), 269 (20785), 243 (30345) nm (L mol cm’). 1  1495, 1434, 1386, 1243, 1219, 1081, 1026, 905, 853, 838, 820, 798, 770, 760, 748, 722,  711, 694, 666, 643, 612, 591, 554, 521, 504 cm . Mp 195 °C. 1  51  RESULTS AND DISCUSSION  2.3 2.3.1  Synthesis and Spectroscopy  The synthetic route to 1,4-di(2-thienyl)-2,5-divinylbenzene 62 and its derivatives 63-66 is outlined in Scheme 2-1. Scheme 2-1  Br2  —_/‘  Br—( ‘s—Br  1) 3 CH C O0H, 2 CO) 3 (CH 0 , S0 Cr0 2 H , 4 3  -Br  2) 4 S0 2 2 H , C 3 CH 0 H, H H 0 2  55  56  3 R._/S_Sn(Bu) PPh 3 CH B r, n-BuLi  R. 4 ) 3 Pd(PPh  57 58 59 60 61 uv. 2 I  62 63 64 65 66  R=H 3 R=CH 13 H 6 R=C 25 H 12 R=C 5 H 6 R=C  67 68 69 70 71  R=H 3 R=CH 13 H 6 R=C 15 C 2 2 R=H 5 H 6 R=C  R=H R = CH 3 R=C 13 H 6 15 C 2 2 R=H R=C 5 H 6  2,5-Dibromo-p-xylene 55 and 2,5-dibromoterephthalaldehyde 56 were prepared according to literature procedures. Compounds 57-61 were prepared via a two-fold Pd(O)-catalyzed Stille cross-coupling reaction between 56 and the appropriate 2-tributyistannyithiophene. Column 52  chromatography was used to purit’ the dialdehydes that were isolated as bright yellow solids. Single-crystal x-ray diffraction studies were carried out on a crystal of the dimethyl-derivative 58 grown from cold (ca. -11 C) dichloromethane. The thermal ellipsoid plot shown in Figure 2-1  illustrates  the  successful  addition  of two  5-methyithienyl-substituents to the  terephthalaldehyde moiety forming the thiophene-phenylene oligomer.  Figure 2-1. Thermal ellipsoid plot of 58. Thermal ellipsoids are drawn at 50% probability. The  hydrogen atoms are omitted for clarity.  The 1 H NMR spectrum of 58 (Figure 2-2) illustrates the resonance pattern that is typical for the alkylated derivatives. The sharp singlets at 6 10.25 and 8.05 are consistent with the precursor 9 and are assigned to the aldehyde CHO and phenyl CH protons. Resonances at 6 6.94 and 6.86 are assigned to the aromatic thienyl C-H protons and the singlet at 6 2.57 is assigned to the aliphatic CH 3 protons. Strong stretching frequencies spanning 1681-1684 cm 1 in the IR spectra of 57-61 confirmed the integrity of the aldehyde functionalities after purification.  53  -  ppm  I  I  9.0  8.0  I  7.0  I  I  I  6.0  I  I  I  5.0  4.0  3.0  Figure 2-2. ‘H NMR spectrum of 58. (400 MHz, 2 C1 ca. 25 °C) CD ,  The solution-phase UV/vis absorption spectra of dialdehydes 57-61 are shown in Figure 2-3 (top) and the data collected in Table 2-1. All spectra possess two distinct absorption bands within the regions of 269-272 nm and 374-413 nm. These are assigned to  ic-.it’  and n7c*  electronic transitions involving the C0 chromophores as the absorption bands have also been observed in 56. The shoulder at 288 nm of the non-derivatized dialdehyde 57 is assigned to a it-t  transition of the thiophene-phenylene oligomer which becomes red-shifted upon  derivatization of the thiophene groups with alkyl substituents. The  it-’W  absorption band of the 54  diphenyl-derivative 61 is further red-shifted due to an increase in conjugation imparted by the phenyl-substituents. Compounds 57-61 exhibit green luminescence in solution with emission maxima between 490 and 548 nm, and quantum yields  F) 1 (c  of 0.39-0.92.  62  I  I  -  250  300  350  400  450  500  550  600  650  700  Wavelength (nm) Figure 2-3. Normalized solution phase UV/vis absorption spectra of 57-61 (top) and 62-66 (bottom) at ca. 25 °C.  55  Table 2-1. UV/vis Absorption Data of Dialdehydes 57-61. Compound  Solution absorptiona -1  maxIflm (/M cm  a  .1  Solution emissiona  )  Quantum Yielda ()  max/flm  57  374 (4600), 269 (29600)  490  0.39  58  401 (5600), 308 (17800), 271 (24700)  523  0.85  59  403(5500),311(18800),272(23500)  530  0.92  60  403 (5400), 311 (18000), 272 (22400)  530  0.89  61  413 (11400), 333 (29300) 270 (22400)  548  0.83  c1 CH . 2  A two-fold Wittig olefination of 57-61 using methyltriphenyiphosphonium bromide afforded compounds 62-66 in good yield (74-84%). Column chromatography was used to purify the compounds that were isolated as either white or yellow solids. The ‘H NMR spectra of compounds 62-66 show three distinct sets of doublet of doublets in the regions around 6 7.00, 5.74, and 5.28 that are characteristic of the two-bond and three-bond coupling of the vinylic protons. An example of this feature is illustrated in the  1  H NMR spectrum of 63 shown in  Figure 2-4. The solution phase UV/vis absorption spectra of 62-66 (Figure 2-3, bottom) show absorption maxima between 276 —280 nm that are assigned to a  ic-t’  transition involving the vinylic C=C  chromophores while the lower energy shoulders are assigned to the  n7t*  transition of the  56  thiophene-phenylene oligomer. Similar features are observed for 66, though the absorption bands are bathochromically shifted due to the larger degree of conjugation.  6.00  ppm  6.0  5.0  5.50  4.0  3.0  Figure 2-4. ‘H NMR spectrum of 63. (400 MHz, , C1 Ca. 25 C) 2 CD  BADTs 67-71 were prepared by irradiating dilute benzene (or xylenes) solutions of 62-66 with UV light (ca. 300 nm) using iodine as the oxidant. The reactions were monitored by UV/vis absorption spectroscopy and terminated when absorption bands of the starting material were no longer present and absorption maxima of the product no longer increased with irradiation. Figure 2-5 illustrates the conversion of 66 to 71 through a series of UV/vis absorption spectra taken at 30s intervals during a typical photolysis experiment. Unlike the parent linear anthradithiophene 52 and its alkylated derivatives, compounds 67-71 are 57  synthesized as single isomers and are readily soluble in common organic solvents at room temperature enabling purification by column chromatography. The solubility of these compounds in common organic solvents such as hexanes and dichloromethane is desirable for ultimately incorporating our BADTs into electronic devices using solution processing techniques. Unfortunately, the diphenyl-derivatized BADT 71 was found to be insoluble and therefore could only be purified by multiple sublimations. These compounds were all isolated as pale yellow solids.  D  a)  0  0 Cl)  250  300  350  400  450  500  Wavelength (nm)  Figure 2-5. UV/vis absorption spectra of 71 recorded at 30s intervals during photolysis in  benzene with dissolved iodine at Ca. 25 °C.  58  The solution phase UV/vis spectra of compounds 67-71 exhibit nearly identical features  (2m  between 304 and 324 nm) and are similar to the absorption spectra of the all-phenyl analogue 28 Compounds 67-71 exhibit blue fluorescence in solution with emission dibenz[a,h]anthracene. maxima between 408 and 439 nm, and quantum yields (Ii) of 0.36  —  0.96 (see Table 2-2) and  green/blue fluorescence in the crystalline state. Table 2-2. UV/vis Absorption Data of BADTs 67-71. Sample  Solution absorptiona 4 -1 Xmax/nm (E/M cm )  Solution  Solid-state  emissiona  emission  Quantum Yield a  X/nm  67  304 (142900), 292 (60000)  408  413  0.36  68  309 (217900), 296 (96300)  425  447  0.56  69  311 (129500),298(52900)  425  453  0.60  70  311 (162000),298(67000)  427  480  0.56  71  324 (89400), 339 (156000),  439  -  0.96  400 (18000) a  C1 CH 2  The ‘H NMR spectrum of the dimethyl derivative 68 possesses a resonance pattern that is consistent with BADTs functionalized at the cL-position of the thiophene groups. The singlet at 6 8.59 is assigned to the thienyl 3-hydrogens which is 0.75 ppm upfield from that of 71. This is 59  likely due to the extended i-e1ectron delocalization over the thienyl groups and the phenyl substituents in the latter. The second singlet at 6 7.17 is assigned to the CH proton of the central phenyl ring of the anthracenyl moiety while the doublets at 6 7.86 and 7.72 are assigned to the remaining aromatic CH protons.  ppm  ppm  8.0  7.850 7.800 7.750 7.700 7.650 7.600  7.0  6.0  5.0  4.0  3.0  Figure 2-6. ‘H NMR spectrum of 68. (400 MHz, 2 C1 Ca. 25 °C) CD ,  60  2.3.2  Cyclic Voltammetry  Cyclic voltammetry (CV) was carried out on the parent 67 in dry DCM containing 0.1 M NjCIO on a Pt-disc working electrode scanning from +0.4 to [(n-Bu) 4  +  1.3 V vs. SCE. The  fIrst scan shows a single irreversible anodic wave at +1.2 V vs. SCE with a weak cathodic feature on the return scan. Interestingly, an increase in current and a decrease in oxidation potential was observed upon successive sweeps suggesting that 67 oxidatively polymerizes electrochemically via a radical mechanism (Scheme 1-2) onto the working electrode forming a thin  film  of poly-67  (Figure  2-7).  Similar observations have  been observed  in  29 anthratetrathiophenes as well.  0 0  C  0 0 Co  C-)  0.4  0.6  0.8  1.0  1.2  1.4  Potential (V) vs SCE Figure 2-7. Cyclic voltammetry of 67 in 2 C1 containing 0.1 M 4 CH NjC10 Scanned [(n-Bu) .  from +0.4 to  +  1.3 V vs SCE for 10 cycles, scan rate = 100 mV s . 1 61  To further this investigation, films of poiy-67 were grown on either gold or indium-doped tin oxide (ITO) substrates. A scanning electron microscopy (SEM) micrograph of a poiy-67 film is given in Figure 2-8 showing a cauliflower-like surface morphology. The UV/vis absorption spectrum of poly-67 exhibits a  max  at 319 nm, 15 nm red-shifted from the monomer (67)  suggesting that there is limited delocalization of electron density between monomeric units. Unfortunately, multiple attempts to characterize the polymer using spectroelectrochemistry failed due to the insolubility and structural instability of the thin films that flake from the surface of the electrode upon successive washes with DCM.  Figure 2-8. SEM micrograph of a poly-67 film electrochemically grown onto a gold on glass  wafer.  62  Electrochemical experiments were also carried out on the dialkyl derivatives 68-70 which all exhibit a single quasi-reversible redox wave in their cyclic voltammograms (see Appendix 3). These redox waves do not increase in intensity upon successive sweeps suggesting that the electropolymerization of 67 likely occurs through the ct-positions of the thienyl groups. On the premise that the HOMO energy level of ferrocene is 4.8 eV below the vacuum level, ’ 30  31  HOMO energy levels of 68-70 were estimated by using their oxidation peak maxima (1.17, 1.16, and 1.15 V respectively) and were calculated to be 5.6, 5.5, and 5.5 eV respectively. These values are consistent with the HOMO level of the dimethyl derivative 68 (5.08 eV) calculated using DFT methods and similar to that estimated for 51 (5.8 eV, Chart 2-1). These values imply good oxidative stability, a feature that is desirable for electronic device applications. 2.3.3  Oxidative Photocyclization of 2,5-dithienyl-1,4-distyrylbenzenes  In order to elucidate the scope of our synthetic strategy, our investigation was extended to include the products formed by the double oxidative photocyclization of 2,5-dithienyl-1,4distyrylbenzenes 72 and 73. Chart 2-2  /  72  \/  73  74  63  The cis,cis-isomer 72 was prepared using the same synthetic strategy used to prepare the all phenyl analogue cis,cis-2,5-diphenyl- 1 ,4-distyrylbenzene. 32 The trans,trans-isomer 73 is readily obtained by heating 72 to reflux in p-xylene containing a catalytic amount of iodine. These isomers are unambiguously characterized as either cis,cis or trans,trans by 1 H NMR spectroscopy (see Appendix 6). For instance, the olefmic protons of the cis,cis-isomer give rise to a pair of doublets appearing at 6 6.71 and 6.67 with a coupling constant of 12 Hz while those of the all-trans isomer appear downfield at 6 7.40 and 7.14 with a coupling constant of 16 Hz. This is consistent with data obtained from the all-cis and all-trans isomers of 2,5-diphenyl-1,4’ 32 distyrylbenzenes.  The authors attribute these differences to the larger degree of planarity  and hence greater conjugation effect along the distyrylbenzene moiety in the trans,trans-isomer. This phenomenon is supported by the absorption spectra of 72 and 73 where the trans,trans isomer possesses a  max  absorption band at 348 nm (molar absorption coefficient of 43700 L  mor’cm’) while the cis,cis-isomer has a  umax  at 311 nm (molar absorption coefficient of 27400  L1 moF’cm ) . The double oxidative photocyclization of both the cis,cis- and trans,trans-isomers afforded a racemic mixture of the novel thiaheterohelicene 74. Thiaheterohelicenes are an emerging class of compounds that are interesting due to the site-selective reactivity of the thiophene group(s) that can be exploited to tune their electronic and chiroptical properties. 34 Compound 74 was purified by flash chromatography followed by multiple precipitations in cold hexane/DCM mixtures which removed any remaining by-products of lower solubility. Single crystals suitable for XRD studies were grown from a concentrated solution of 74 in cold (ca. —11 °C) DCM. The thennal ellipsoid plot of 27 is shown in Figure 2-9a.  64  (a)  (b)  1 111  11  iv  Figure 2-9. (a) Thermal ellipsoid plot of 74. Thermal ellipsoids are drawn at 50% probability.  The hydrogen atoms are omitted for clarity. (b) Packing diagram of 74.  The thiaheterohelicene possesses Ci symmetry and crystallizes as a racemate. Aromatic rings B-E all deviate from planarity while the thienyl ring A remains planar. A dihedral angle of 51°  between the mean planes of A and E illustrates the large degree of twisting in the heterohelicene. For comparison, the dihedral angle between the terminal aromatic rings in 35 and [5]carbohelicene trithia[5]heterohelicene 36 are 37° and 49° respectively.  This large  dihedral angle is somewhat surprising since a lower degree of steric crowding would be expected due to the orientation of the thiophene moiety A with its ci and n-hydrogen atoms situated on the periphery of the thiaheterohelicene framework. The dihedral angles between the remaining mean planes of 74 are as follows: A-B 11°, B-C 15°, C-D 12°, and D-E 14°. The crystal packing of 74 is shown in Figure 2-9b. The S S distance (ca. 3.29 A) between  65  alternating P and M enantiomers (i.e.,  i-u  and iii-iv) is shorter than the sum of their van der  Waals radii (1.80 A for S) suggesting the presence of intermolecular interactions that give rise to a one-dimensional chain-like structure. This stacking arrangement is unique since both thiophene moieties in 74 participate in intermolecular interactions, a feature that may be an attractive approach to thiaheterohelicene self-assembly studies. In addition, a short intermolecular distance of 3.33 A is observed between adjacent enantiomers, ii and iii, suggesting that it- it interactions also contribute to the intimate contact between P and M isomers in the single crystal.  2.4  CONCLUSION  In this Chapter, the preparation of a series of bent anthradithiophenes was described. Dialdehydes 57-61 were prepared via Stille cross coupling of 2,5-dibromoterephthalaldehyde 56 with the appropriate 2-tributylstannylthiophene. A two-fold Wittig olefination of 57-61 using methyltriphenylphosphonium bromide offered the divinyl-compounds 62-66. Photochemical cyclization of 62-66 using iodine as the oxidant afforded BADTs 67-71 in low-to-moderate yields. All compounds were characterized using a variety of spectroscopic techniques, mass spectrometry, and elemental analysis. Apart from the diphenyl derivative 71, all BADTs were soluble in common organic solvents including hexanes, DCM, and chloroform and could be purified using column chromatography. Cyclic voltammetry experiments revealed that 67 polymerizes electrochemically upon successive potential sweeps to afford thin films that are structurally unstable. The cyclic voltammogram traces of the dialkyl derivatized BADTs 68-71 were very similar exhibiting a quasi-reversible redox wave that did not increase in current upon successive sweeps, thus providing indirect evidence that 67 polymerizes through the cL-carbon of  66  the thienyl groups. In order to extend the scope of our synthetic strategy, oxidative photocyclization reactions were carried out on the novel cis,cis- and trans,trans-2,5-dithienyl1 ,4-distyrylbenzenes. Both reactions yielded a racemic mixture of the heterohelicene 74 which has been characterized by a variety of spectroscopic techniques and single-crystal x-ray diffraction studies.  67  2.5  REFERENCES  1.  Yamamoto, T.; Takimiya, K., J Am. Chem. Soc. 2007, 129, 2224-2225.  2.  Takimiya, K.; Ebata, H.; Sakamoto, K.; Izawa, T.; Otsubo, T.; Kunugi, Y., I Am. Chem.  Soc. 2006, 128, 12604-12605. 3.  Gao, J.; Li, R.; Li, L.; Meng,  Q.; Jiang, H.; Li, H.; Hu, W., Adv. Mater.  2007, 19, 3008-  3011. 4.  Ebata, H.; Miyazaki, E.; Yamamoto, T.; Takimiya, K., Org. Lett. 2007, 9, 4499-4502.  5.  Wex, B.; Kaafarani, B. R.; Schroeder, R.; Majewski, L. A.; Burckel, P.; Grell, M.;  Neckers, D. C.,J Mater. Chem. 2006, 16, 1121-1124. 6.  Xiao, K.; Liu, Y.; Qi, T.; Zhang, W.; Wang, F.; Gao, J.; Qiu, W.; Ma, Y.; Cui, G.; Chen,  S.; Zhan, X.; Yu, G.; Qin, J.; Hu, W.; Zhu, D.,I Am. Chem. Soc. 2005, 127, 13281-13286. 7.  losip, M. D.; Destri, S.; Pasini, M.; Porzio, W.; Pernstich, K. P.; Batlogg, B., Synth. Met.  2004, 146, 25 1-257. 8.  Li, X.-C.; Sirringhaus, H.; Gamier, F.; Holmes, A. B.; Moratti, S. C.; Feeder, N.; Clegg,  W.; Teat, S. J.; Friend, R. H., .J Am. Chem. Soc. 1998, 120, 2206-2207. 9.  Laquindanum, J. G.; Katz, H. E.; Lovinger, A. J., I Am. Chem. Soc. 1998, 120, 664-672.  10.  Laquindanum, J. G.; Katz, H. E.; Lovinger, A. J.; Dodabalapur, A., Adv. Mater. 1997, 9,  36-39. 11.  Payne, M. M.; Parkin, S. R.; Anthony, J. E.; Kuo, C.-C.; Jackson, T. N., I Am. Chem.  Soc. 2005, 127, 4986-4987. 12.  Dickey, K. C.; Anthony, J. E.; Loo, Y.-L., Adv. Mater. 2006, 18, 1721-1726.  13.  Roncali, J., Chem. Rev. 1992, 92, 711-738.  14.  Shen, H.-C.; Tang, J.-M.; Chang, H.-K.; Yang, C.-W.; Liu, R.-S., I Org. Chem. 2005, 68  70, 10113-10116. 15.  Tovar, J. D.; Swager, T. M., I Organomet. Chem. 2002, 653, 215-222.  16.  Goldfinger, M. B.; Crawford, K. B.; Swager, T. M., I Am. Chem. Soc. 1997, 119, 4578-  4593. 17.  Chen, Z. K.; Huang, W.; Wang, L. H.; Kang, E. T.; Chen, B. J.; Lee, C. S.; Lee, S. T.,  Macromolecules 2000, 33, 9015-9025. 18.  Xia, C.; Advincula, R. C., Macromolecules 2001, 34, 6922-6928.  19.  Berridge, R.; Wright, S. P.; Skabara, P. J.; Dyer, A.; Steckler, T.; Argun, A. A.;  Reynolds, J. R.; Harrington, R. W.; Clegg, W., I Mater. Chem. 2007, 17, 225-23 1. 20.  Jousselme, B.; Blanchard, P.; Gallego-planas, N.; Levillain, E.; Delaunay, J.; Allain, M.;  Richomme, P.; Roncali, J., Chem. Eur. 1 2003, 9, 5297-5306.  21.  Wilson, P.; Lacey, D.; Sharma, S.; Worthington, B., Mo!. Ctyst. Liq. Cryst. Sci. Tech.  2001, 368, 279-292. 22.  Li, J. J.; Carson, K. G.; Trivedi, B. K.; Yue, W. S.; Ye,  Q.;  Glynn, R. A.; Miller, S. R.;  Connor, D. T.; Roth, B. D.; Luly, J. R.; Low, 3. E.; Heilig, D. J.; Yang, W.; Qin, S.; Hunt, S.,  Bioorg. Med. Chem. 2003, 11,3777-3790. 23.  Weber, G.; Teale, F. W. J., Trans. Faraday Soc. 1957, 53, 646-55.  24.  SAIN7, Version 7.03A; Bruker AXS Inc.: Madison, Wisconsin, USA 1997-2003.  25.  SADABS, V.2.10; Bruker AXS Inc.: Madison, Wisconsin, 2003, 2003.  26.  Altomare, A.; Cascarano, G.; Giacovazzo, C.; Guagliardi, A., I AppL Ciystallogr. 1994,  27, 1045-1050. 27.  SHELXTL, Version 5.1; BrukerAXS Inc.: Madison, Wisconsin USA, 1997.  28.  Karcher, W.; Fordham, R. J.; Dubois, J. J.; Glaude, P. G. J. M.; Ligthart, J. A. M.,  69  Spectral Atlas of Polycyclic Aromatic Compounds. D. Reidel Publishing Company: Dordrecht, The Netherlands, 1985. 29.  Brusso, J. L.; Hirst, 0. D.; Dadvand, A.; Ganesan, S.; Cicoira, F.; Robertson, C. M.;  Oakley, R. T.; Rosei, F.; Perepichka, D. F., Chem. Mater. 2008, 20, 2484-2494. 30.  Bredas, J. L.; Silbey, R.; Boudreaux, D. S.; Chance, R. R., I Am. Chem. Soc. 1983, 105,  6555-6559. 31.  Pommerehne, J.; Vestweber, H.; Guss, W.; Mahrt, R. F.; Baessler, H.; Porsch, M.; Daub,  J., Adv. Mater. 1995, 7, 55 1-554. 32.  Xie, Z.; Yang, B.; Liu, L.; Li, M.; Lin, D.; Ma, Y.; Cheng, G.; Liu, S., I Phys. Org.  Chem. 2005, 18, 962-973. 33.  Jacobs, S.; Levers, W.; Verreyt, G.; Geise, H. J.; De Groot, A.; Dommisse, R., Synth.  Met. 1993, 61, 189-193. 34.  Collins, S. K.; Vachon, M. P., Org. Biomol. Chem. 2006,4, 25 18-2524.  35.  Nakagawa, H.; Yamada, K.; Kawazura, H.; Miyamae, H., Acta Ciys4 Sect. C: Ciyst.  Struct. Commun. 1984, C40, 1039-1041. 36.  Goedicke, C.; Stegemeyer, H., Tetrahedron Lett. 1970, 12, 937-940.  70  CHAPTER 3 Solid—State Structures of Bent Anthradithiophene Single Crystals and Films  3.1  INTRODUCTION  Single-crystal and thin-film organic field effect transistors (OFETs) are three terminal devices that rely on an electric field to modulate electric current passing through an organic semiconductor. Although these devices currently under perform metal-oxide-semiconductor FETs,’ they offer some potential advantages such as vapour/solution processability, improved substrate compatibility, and chemicallstructural tuneability. 2 It has been suggested that OFETs may fmd applications in radio-frequency technologies, 3 sensors, ’ 4  identification tags, pixel  drives, and switching elements in flexible electronic displays. 68 One of the most common thin-film OFET architectures is the top contact configuration illustrated in Figure 3-1. The organic semiconductor is deposited onto a dielectric material possessing an underlying gate electrode. Source (S) and drain (D) electrodes are then deposited onto the semiconductor, completing the device. In “p-channel” OFETs, positive charges (i.e., holes) are injected into the organic semiconductor upon application of a negative source-to-gate potential (V5G).’° Charge carrier formation is controlled by the magnitude of VSG giving the  *  A version of this chapter has been published. Pietrangelo, A.; MacLachlan, M.3.; Wolf, M.O.; Patrick, B.O. Org. Lett. 2007, 9, 357 1-3573.  71  device its field-effect properties. The holes are then able to migrate through a narrow channel generated at the organic semiconductor/dielectric interface upon the application of a negative source-to-drain potential (VSD).” 4  ,,,,,,,,,, ,,,,,,,,,,, //////////  Dielectric Layer  VSD  <0 V, VSG  <  0V  Figure 3-1. Illustration of a top-contact OFET and the molecular layer structure of the  conducting channel. Low molecular weight organic semiconductors such as oligoacenes are generally fabricated into a device as either a single crystal or as a highly ordered polycrystalline thin film grown via thermal evaporation. ’ 1  10, 11  In the solid-state, oligoacenes tend to adopt an edge-to-face  herringbone layered packing motif where the long molecular axes are orientated parallel to each other and tilted with respect to the substrate surface (Figure ’ 2 pentacene’  13  and sexithiophene-based’ ’ 4  15  31).1  Experimental studies on  FETs have shown that charge transport is favoured  in the direction parallel to the layers, suggesting that molecular orientation can influence device performance. In addition, theoretical studies performed by Brédas and co-workers have shown that the amplitude of the interchain transfer integrals (that express the ease by which charge is transferred between adjacent molecules) is highly sensitive to molecular displacements; these 72  include slipping along both their short and long molecular axis, and shifts in interplanar 6 The results of this study have motivated synthetic chemists to develop new distances.’ functionalized materials in order to modify packing motifs in the crystalline phase such that electronic coupling between adjacent molecules can be improved. 9 In Chapter 2, the synthesis and spectroscopy of a series of functionalized bent anthradithiophenes that are anticipated to be good candidates for organic semiconductors in field effect transistors were reported. In this Chapter, their solid-state packing structures as single crystals and as films grown via thermal evaporation are discussed. The objective of this work was to determine how the substituents influence packing in the solid-state. For the BADT derivatives that adopt a cofacial stacking arrangement, translational displacements between adjacent molecules were characterized using a method developed by Curtis and co-workers where slipping along the long and short molecular axis is described by pitch (P) and roll (R) angles (Figure 3-2).’ Finally, the UV/vis absorption and luminescence spectra of films prepared from BADTs 67 and 70 are reported.  73  (a)  (b)  LR,  (c) long molecularaxis  short molecular axis  Figure 3-2. (a) Pitch angle (F) describing intermolecular slipping along the long molecular axis (view down short molecular axis). (b) Roll angle (R) describing intermolecular slipping along the short molecular axis (view down long molecular axis). (c) Long and short molecular axes of 67.  74  3.2 3.2.1  EXPERIMENTAL General  Materials and Equipment. Films of BADTs 67-70 were prepared by vacuum evaporation onto Corning® cover glass substrates at temperatures between 150 and 200 °C at a pressure of 0. 1 to 1 Ton. The substrate temperature was ca. 25 °C. All glass substrates were cleaned with a sulfuric acid/hydrogen peroxide mixture (4:1) prior to use in order to remove surface organic contaminants. Powder x-ray diffraction measurements were carried out using a Bruker D8 Advance diffractometer with graphite monochromated Cu-Kc radiation. All fluorescence spectra were obtained on a Photon Technology International QuantaMaster fluorimeter. Solidstate absorption spectra of 67-70 were obtained from drop-casted films deposited from DCM solutions onto Corning® cover glass substrates using a Varian Cary 5000 UV-vis-near-IR spectrophotometer. X-ray Crystallographic Analysis. Suitable crystals of BADTs 67-70 were mounted on a glass  fibre and data for each compound were collected at 173 (1) K. All structures were solved by direct methods 18 and refined using the SHELXTL 19 crystallographic software package of Bruker-AXS. All data were collected and integrated using the Bruker SAINT ° software 2 package. All data were corrected for absorption effects using the multi-scan technique (SADABS) and corrected for Lorentz polarization. ’ All measurements were made on a Bruker 2 X8 APEX II diffractometer with graphite monochromated Mo-KcL radiation. The structures were obtained at UI3C by Dr. Brian Patrick. Crystallographic data for 68, 69, and 71 are tabulated in Appendi’x 1.  75  The data for 67 were collected to a maximum 29 value of 50.2°. Data were collected in a series of  4 and  o scans in  0.500  oscillations with 20.0 second exposures. Compound 67  crystallizes with the molecule residing on an inversion center. All non-hydrogen atoms were refmed anisotropically. All hydrogen atoms were included in calculated positions but were not refined. The data for 68 were collected to a maximum 29 value of 55.9°. Data were collected in a series of  4  and o scans in 0.50° oscillations with 10.0 second exposures. Compound 68  crystallizes with one half-molecule residing on an inversion center. All non-hydrogen atoms were refined anisotropically. All hydrogen atoms were included in calculated positions but were not refined. The data for 69 were collected to a maximum 29 value of 56.0°. Data were collected in a series of  4  and co scans in 0.50° oscillations with 10.0 second exposures. Compound 69  crystallizes with one half-molecule residing on an inversion center. All non-hydrogen atoms were refined anisotropically. All hydrogen atoms were included in calculated positions but were not refined. The data for 70 were collected to a maximum 29 value of 50.2°. Data were collected in a series of  4’ and  o scans in 0.50° oscillations with 30.0 second exposures. Compound 70  crystallizes with one half-molecule residing on an inversion center. All non-hydrogen atoms were refined anisotropically. All hydrogen atoms were included in calculated positions but were not refined.  76  Suitable crystals of 71 were mounted on a glass fibre and the data collected at 150 K on a D8 goniostat equipped with a Bruker APEXII CCD detector at Beamline 11.3.1 at the Advanced Light Source (Lawrence Berkeley National Laboratory) using synchrotron radiation tuned to 0.7749  =  A. Synchrotron radiation was required due to the thinness of the crystal. The structure  was solved using direct methods and refined using the SHELXTL’ 9 crystallographic software package of Bruker-AXS. A series of 3-s data frames measured at 0.2° increments of o were collected to calculate a unit cell. For data collection, 3-s frames were measured at 0.3° intervals of o and  4. The data frames were collected using the program APEX2 and processed using the  program Bruker SAINT. ° Data were corrected for absorption effects using the multi-scan 2 technique (SADABS). ’ Compound 71 crystallizes with one-half molecule residing on an 2 inversion centre.  77  3.3  RESULTS AND DISCUSSION  3.3.1  Solid-State Crystal Structures and Packing  Crystals of 67 and 68 suitable for single-crystal x-ray diffraction (XRD) studies were grown from cold (ca. —11 C) DCM. Both the parent 67 and the dimethyl derivatized BADT 68 crystallize in the monoclinic 1 P2 / n space group with two molecules in the unit cell. The rigid conjugated molecules are planar and show a small extent of cofacial overlap between adjacent molecules (Figure 3-3b,d).  (a)  (b)  Si  C9  C2  C6  Si*  (c)  (d)  \La Figure 3-3. (a) Thermal ellipsoid plot of 67. The hydrogen atoms are omitted for clarity.  Thermal ellipsoids are drawn at 50% probability. (b) View down the stacking axis of two cofacial molecules of 67. (c) Crystal packing of 67. Dashed lines illustrate short contacts (ca. 3.47  A). (d) View down the stacking axis of two cofacial molecules of 68.  78  The pitch and roll angles of 67 (see Table 3.1 for selected bond lengths) are 13° and 28° respectively. An interplanar distance of 3.46 A indicates the presence of it-it interactions along the intermolecular stacking axis. For comparison, dibenz[a,hjanthracene crystallizes into a 1 or Pcab) with no intermolecular cofacial interactions. herringbone arrangement (P2 2226 Thus,  the incorporation of thienyl groups appears to enhance it-stacking in the crystal lattice, a feature that is highly desirable in LMW organic semiconductors. In addition, the it-slipped stacks are aligned into edge-to-face herringbone arrays where four intermolecular close-contacts are observed between each molecule of 67 and four others in adjacent stacks (Figure 3-3c). For instance, the distance between the sulfur atoms in a molecule of 67 (i.e., Si and Si *) and a single C9 atom from two adjacent molecules is 3.47 A, a distance shorter than the sum of their van der Waals radii (3.55 A). This same distance is observed between the C9 and C9* atoms of each molecule and the sulfur atoms of two additional molecules. Interestingly, this contact distance is shorter than those observed between close-carbon contacts in adjacent molecules of pentacene (3.6-3.8 A), ° and suggests that a single crystal of 67 may have a two dimensional 273 electronic structure.  79  Table 3-1. Bond Lengths of BADT 67. Bond Length! A  Bond Length IA C(1)-C(2)  1.347(3)  C(4)-S1  1.725(2)  C(1)-S(1)  1.715(2)  C(5)-C(6)  1.35 1(3)  C(2)-C(3)  1.452(3)  C(6)-C(7)  1.436(3)  C(3)-C(4)  1.388(3)  C(7)-C(9)  1.394(3)  C(3)-C(5)  1.429(3)  C(7)-C(8)  1.435(3)  C(4)-C(8)  1.432(3)  C(8)-C(9)  1.389(3)  An interplanar distance of 3.28  A between adjacent molecules of 68 (Figure 3-3d) indicates  the presence of t-it interactions along the intermolecular stacking axis. The pitch and roll angles are 4Y and 44 respectively; hence, it appears that the methyl substituents induce a large degree of slipping along both the short and long molecular axes compared to the parent. In addition, there is no evidence of close contacts between adjacent stacks. This packing feature has been observed in 51 (Chart 2-2)’ and suggests that a single crystal of 68 may have a one-dimensional electronic structure. Single crystals of the dihexyl (69) and didodecyl (70) derivatives were grown from cold (ca. -41 °C) chloroform and their structures determined by XRD. Compound 69 crystallizes into the monoclinic P2 /c space group with two molecules in the unit cell. In the crystal lattice, both 1 hexyl chains are in a conformation that extends above and below the aromatic plane of the BADT framework at 39° angles (Figure 3-4).  80  I  (b)  “ 3_  —  -,.  •  -: --4  *  --.  _-4-___  ,*-  -0  *-_-  .*-v  —•  e ‘—.  ;_/  ,—: r  •_  >  Figure 3-4. Packing diagram of 69. (a) View along short molecular axis. The hydrogen atoms  are omitted for clarity. Thennal ellipsoids are drawn at 50% probability. (b) View perpendicular to the molecular plane of the stacking axis. (c) Space-filling diagram of 69. Sulfur atoms are yellow, sp -hybridized carbon atoms are grey, and sp 3 -hybridized carbon atoms are purple. 2  Unlike 67 and 68, there is no evidence of cofacial ic-ic interactions in the crystalline phase of 69 due to the large degree of slipping (pitch angle, 15°; roll angle, 72°) between adjacent coplanar molecules along their short molecular axis (Figure 3-4b). This could be due to steric effects imparted by the hexyl substituents, a phenomenon that has also been observed in a dihexyloxy-derivatized fluorinated tetracene. 32  81  The didodecyl derivatized BADT 70 crystallizes into the triclinic P-i space group with a single molecule in the unit cell. Functionalizing the thienyl cL-positions with dodecyl chains regenerates the cofacial stacking arrangement with pitch and roll angles of 19° and 48° respectively (Figure 3-Sb). In the crystal lattice, both dodecyl chains are in a conformation that extends above and below the aromatic plane of the BADT framework at 46° angles.  (a)  (b)  (c)  Figure 3-5. (a) Thermal ellipsoid plot of 70. The hydrogen atoms are omitted for clarity.  Thermal ellipsoids are drawn at 50% probability. (b) View down the “stacking axis” of two cofacial molecules of 70 with dodecyl chains omitted. (c) Space-filling diagram of 70 illustrating packing structure. Sulfur atoms are yellow, sp -hybridized carbon atoms are grey, 3 and sp -hybridized carbon atoms are purple. 2  82  The interplanar stacking distance of 3.49 A is indicative of 7t-1t interactions along the stacking axis. In the solid state, the molecules are organized into a lamellar packing arrangement with the stacks separated by insulating dodecyl chains (Figure 3-5c). The lack of contact between the  it-  stacks suggests a one-dimensional electronic structure in the crystal. Single crystals of the diphenyl-derivatized BADT 71 were grown from a refluxing solution of p-xylene that was cooled to room temperature and the structure determined by )(RD.  (a)  (b)  Figure 3-6. (a) View down the short molecular axis of 71. The hydrogen atoms are omitted for clarity. Thermal ellipsoids are drawn at 50% probability. (b) Crystal structure of 71 showing two of the eight close contacts between the edge of one acene and the face of another.  83  Compound 71 crystallizes into a monoclinic P2 /c space group with two molecules in the unit 1 cell. The rigid conjugated structure is slightly twisted out of planarity while the pendant phenyl rings are rotated out of the plane of the thiophene groups at an angle of 210 (Figure 3-6a). In the solid state, 71 adopts an edge-to-face herringbone packing motif where the tilt angle between  two mean planes of the BADT framework is  330,  compared to 45° of the all-carbon analog  dibenz[a,h]anthracene and 52° in pentacene. There are eight intermolecular close-contacts in these edge-to-face structures that link a molecule of 71 with four others in the lattice. The two types of contacts are shown in Figure 3-6b. The closest intermolecular C-C distances are 3.29 and 3.33 A. These distances are shorter than the closest intermolecular C-C distances observed in pentacene, phenylated derivatives of pentacene, 33 and 2226 dibenz[a,h]anthracene and may lead to strong electronic coupling between adjacent molecules in the crystalline lattice. 3.3.2  Powder X-ray Diffraction Analyses of BADT Films  The XRD pattern of a film of 67 prepared by vacuum evaporation exhibits two strong  reflections corresponding to the (10-1) and (20-2) planes assigned from the diffraction pattern calculated from the single-crystal XRD data. The thin film is highly crystalline, with reflections indicating that the molecules are oriented with their long molecular axis nearly perpendicular (ca. 77°) to the substrate surface, a phenomenon seen in oligothiophenes as well as in the linear anthradithiophenes prepared by Katz and co-workers. ’ 4  14, 34  This packing orientation is  favourable for electronic device applications as the direction of the t-orbital overlap is parallel to the substrate surface and coincides with the plane in which a current must flow.  84  (10-1)  (a)  s/if//I//i  /1/i//i! D (‘3 (40-4)  > Cl)  (b) C  0  ,  •  0  —  —  .  ;  •  -  ;e  <  • ..  •  .  -  0 .  ..  ••  .  0•  (004) (002)  5  (003)  10  15  20  25  30  35  40  Diffraction Angle, 29 I degree Figure 3-7. X-ray diffractograms and schematic representations of the structural orientation of (a) 67 and (b) 70 on glass substrates (parallel to the x-axes) deposited by vacuum evaporation.  The XRD pattern of a film of 70 prepared by vacuum evaporation exhibits six strong reflections that correspond to the (001) through (006) planes (Figure 3-7b). The molecules are oriented with their long molecular axes inclined approximately  470  with respect to the (001)  plane that is parallel to the substrate surface. These reflections are consistent with those observed in films prepared from the didodecyl derivative of LADT 52 (Chart 2-1), suggesting  85  that this compound packs into a similar arrangement as The XRD pattern of a film of 68 suggests that there are two phases present (Figure 3-8a). The  two sharp reflections at 11.4 and  23.00  20 correspond to the (10-1) and (20-2) planes of the  P2 i/n space group.  %. 0  %  %  (a)  ‘.‘  \  N  >  .4—  U)  0 C  -I—  (b)  5  10  15  20  25  30  Diffraction AngIe, 29 / degree Figure 3-8. X-ray diffractograms and schematic representations of the structural orientation of (a) 68 and (b) 69 on glass substrates (parallel to the x-axes) deposited by vacuum evaporation.  These assignments are supported by the single-crystal XRD data and are consistent with the diffraction pattern obtained from crystals of 68. The molecules are inclined approximately  350  86  with respect to the (10-1) plane that is parallel to the substrate surface. The additional reflections observed at 10.8 and 22.4° 20 are absent in both the calculated and experimental diffraction patterns and are shifted approximately 0.6° 20 from the reflections assigned to the (10-1) and (20-2) planes. Similar features have been observed in the XRD diffractogram of a pentacene thin-film grown onto a silica substrate using molecular beam deposition techniques. These features have been attributed to the coexistence of two phases, a “thin-film” phase and a “single crystal” phase that form under certain deposition conditions.’ 3 The diffraction pattern obtained from a film of 69 exhibits four sharp reflections at 20  =  5, 10,  15, and 20° (Figure 3-8b). These reflections are inconsistent with those calculated from the single-crystal )(RD data and those obtained experimentally from crystals of 69 suggesting that the dihexyl derivatized BADT adopts a different packing motif in the evaporated film. Interestingly, this diffraction pattern is strikingly similar to that obtained from a film of 70 (Figure 3-7b). Although we can only speculate on the packing structure of 69, the similarities between the diffraction patterns accompanied by the higher angle reflections suggests that like the didodecyl derivative, the dihexyl derivative also adopts a lamellar packing arrangement in the film. 3.3.3  Solid-State Absorption and Luminescence Properties of Films  The solid-state UV/vis absorption spectra of drop-cast films of 67-70 exhibit near identical features with  ranging between 280 and 311 nm. Representative spectra of 67 and 70 are  shown in Figure 3-9. The high energy peaks in the solid-state emission spectrum of 67 are similar to those found in the solution phase spectrum (Figure 3-9a) and 70. At longer wavelengths however, the emission intensity from the thin film is greater and a new peak is  87  present at 486 nm. The solid-state emission spectrum of 70 is red-shifted relative to solution, a feature that is likely attributed to intermolecular interactions in the microcrystalline film, 35 where t-staeking has been observed in the solid-state structures.  D  ct  a) C)  C -Q 0 Cl)  -o ci) N  E 0  z  250  300  350  400  450  500  Wavelength (nm) Figure 3-9. (a) Solid-state TJV/vis absorption spectrum of 67 (black-solid). Emission spectrum of 67 in solution (red-dash) and as a thin film (blue-dot). (b) Solid-state UV/vis absorption spectrum of 70 (black-solid). Emission spectrum of 70 in solution (red-dash) and as a thin film (blue-dot). All spectra were taken at Ca. 25 C.  88  CONCLUSION  3.4  In this chapter, the solid-state packing motifs of crystalline BADTs 67-71 in the single crystal were described. The unsubstituted BADT 67 packs in a slipped cofacial stacking arrangement with  it- it  interactions along the intermolecular stacking axis. This motif has not been observed  in the all-phenyl analog, dibenz[a,h]anthracene, suggesting that the thiophene units enhance  it-  stacking in the crystal lattice. The alkyl derivatized BADTs 68-70 adopt similar packing motifs with varying degrees of slipping along their long and short molecular axes. Unfortunately, a trend relating the length of the alkyl substituent and the pitch and roll angles associated with the packing motif was not observed. Finally, the diphenyl derivative, 71, packs into an edge-to-face herringbone arrangement that is common in many phenyl-derivatized and non-derivatized oligoacenes, Single-crystal and powder XRD studies have shown that films prepared via vacuum evaporation are highly crystalline with a preferred specific orientation relative to the substrate surface. Films of 67 and 70 possess reflections that are consistent with the single crystal data suggesting that packing in the film is similar to packing in the single crystal. In addition, molecules of 67 are oriented nearly perpendicular to the substrate surface, a feature that is highly desirable for thin-film OFETs. Films of the dimethyl derivative were found to possess reflections that were both consistent and inconsistent with the single-crystal data suggesting the presence of two phases in the film. Finally, films of the dihexyl derivative 69 were found to possess a set of reflections that were inconsistent with those calculated from the single-crystal data suggesting the presence of a new polymorph in the thin film.  89  REFERENCES  3.5 1.  Horowitz, G., J Mater. Res. 2004, 19, 1946-1962.  2.  Facchetti, A., Mater. Today 2007, 10, 28-37.  3.  Subramanian, V.; Chang, P. C.; Lee, J. B.; Molesa, S. E.; Volkman, S. K., IEEE Trans.  Comp. Pack. Tech. 2005, 28, 742-747. 4.  Lovinger, A. J.; Davis, D. D.; Rue!, R.; Torsi, L.; Dodaba!apur, A.; Katz, H. E., J  Mater. Res. 1995, 10, 2958-2962. 5.  Katz, H. E.; Hong, X. M.; Dodabalapur, A.; Sarpeshkar, R., I App!. Phys. 2002, 91,  1572-1576. 6.  Katz, H. E.; Bao, Z., I Phys. Chem. B 2000, 104, 671-678.  7.  Kitamura, M.; Imada, T.; Arakawa, Y., Jpn. I App!. Phys. 2003, 42, 2483-2487.  8.  Huitema, H. E. A.; Gelinek, G. H.; Van der Putten, J. B. P. H.; Kuijk, K. E.; Hart, K. M.;  Cantatore, E.; De Leeuw, D. M., Adv. Mater. 2002, 14, 1201-1204. 9.  Anthony, J. E., Chem. Rev. 2006, 106, 5028-5048.  10.  Dimitrakopoulos, C. D.; Malenfant, P. R. L., Adv. Mater. 2002, 14, 99-117.  11.  De Boer, R. W. I.; Gershenson, M. E.; Morpurgo, A. F.; Podzorov, V., Phys. Status  SolidiA 2004, 201, 1302-1331. 12.  Minakata, T.; Nagoya, I.; Ozaki, M., I App!. Phys. 1991, 69, 73 54-7356.  13.  Dimitrakopoulos, C. D.; Brown, A. R.; Pomp, A., I AppL Phys. 1996, 80, 250 1-2508.  14.  Servet, B.; Horowitz, G.; Ries, S.; Lagorsse, 0.; Alnot, P.; Yassar, A.; Deloffre, F.;  Srivastava, P.; Hajlaoui, R., Chem. Mater. 1994, 6, 1809-18 15. 15.  Gamier, F.; Yassar, A.; Hajlaoui, R.; Horowitz, G.; Deloffre, F.; Servet, B.; Ries, S.;  Alnot, P., 1Am. Chem. Soc. 1993, 115, 8716-8721. 90  16.  Bredas, J. L.; Calbert, I. P.; Da Silva Filho, D. A.; Cornil, 3., Proc. Nat!. Acad. Sci. U S.  A. 2002, 99, 5804-5809. 17.  Curtis, M. D.; Cao, J.; Kampf J. W., I Am. Chem. Soc. 2004, 126, 43 18-4328.  18.  Altomare, A.; Cascarano, G.; Giacovazzo, C.; Guagliardi, A., I App!. Ciystallogr. 1994,  27, 1045-50. 19.  SHEIXTL, 5.1; Bruker AXS Inc.: Madison, Wisconsin, USA, 1997.  20.  SAINT, Version 7.23A; Bruker AXS Inc.: Madison, Wisconsin, USA, 1997-2003.  21.  SADABS, 2.10; Bruker AXS Inc.: Madison, Wisconsin, USA, 2003.  22.  Iball, J., Nature 1936, 137, 361.  23.  IbalI, 3.; Morgan, C. H.; Zacharias, D. B., I Chem. Soc., Perkin Trans. 2: Phys. Org.  Chem. 1975, 12, 1271-1272. 24.  Krishnan, K. S.; Banerjee, S., Z Kristallogr. 1935, 91, 170-172.  25.  Robertson, 3. M.; White, 3. G., I Chem. Soc. 1947, 1001-1010.  26.  Robertson, 3. M.; White, 3. G., I Chem. Soc. 1956, 925-391.  27.  Campbell, R. B.; Robertson, J. M.; Trotter, J.,Acta Ciyst. 1962, 15, 289-90.  28.  Holmes, D.; Kumaraswamy, S.; Matzger, A. J.; Vollhardt, K. P. C., Chem. Eur. I 1999,  5, 3399-34 12. 29.  Siegrist, T.; Kioc, C.; Schon, J. H.; Batlogg, B.; Haddon, R. C.; Berg, S.; Thomas, G. A.,  Angew. Chem.  30.  mt. Ed. 2001, 40, 1732-1736.  Mattheus, C. C.; Dros, A. B.; Baas, 3.; Meetsma, A.; de Boer, 3. L.; Paistra, T. T. M.,  Acta Ciyst., Sect. C: Cryst. Struct. Commun. 2001, C57, 939-941. 31.  Ebata, H.; Miyazaki, E.; Yamamoto, T.; Takimiya, K., Org. Lett. 2007, 9, 4499-4502.  32.  Chen, Z.; Mueller, P.; Swager, T. M., Org. Lett. 2006, 8, 273-276.  91  33.  Miao,  Q.; Chi, X.; Xiao, S.; Zeis, R.; Lefenfeld, M.; Siegrist, T.; Steigerwald, M. L.;  Nuckolls, C., J Am. Chem. Soc. 2006, 128, 1340-1345. 34.  Laquindanum, J. G.; Katz, H. E.; Lovinger, A. J., I Am. Chem. Soc. 1998, 120, 664-672.  35.  Dabestani, R.; Ivanov, I. N., Photochem. Photobiol. 1999, 70, 10-34.  92  CHAPTER4 Nonlinear Optical  Properties of Schiff Base-Containing  Conductive Polymers Electrodeposited in Microgravity*  4.1 4.1.1  INTRODUCTION Background  Materials that exhibit large nonlinear optical (NLO) responses are required for future optical and photonic technologies that will be used for telecommunications and information processing and storage applications.” 2 Conjugated polymers are emerging as promising candidates owing to their inherent extended delocalization of polarizable t-electrons. 3 Polymers offer advantages over inorganic crystalline materials as they merge the possibility of tuneable NLO properties with solution processability and enhanced mechanical stability. A NLO response is a material phenomenon that arises from its interaction with light. 2 As light traverses a material, the oscillating electric fields induce polarization within the material. At low field intensities, the electric polarization, P (electric dipole moment per unit volume), is linearly proportional to the electric field, E (Figure 4-la), and is described by equation I, where s is the permittivity of free space, -a arid cv,, are the output and input frequencies, respectively, and m is the linear susceptibility tensor.  *  A portion of this chapter has been published. Pietrangelo, A.; Sih, B.C.; Boden, B.N.; Wang, Z; Li, K.C.; MacLachian, M.J.; Wolf, M.O. Adv. Mater. 2008, 20, 2280-2284.  Q.; Chou,  permittivity of free space, -con and o are the output and input frequencies, respectively, and is the linear susceptibility tensor. P(—ao)//  (a)  (1)  ; =z’(—a ) 0 ) E(co o  P  (b)  -  (1)  c)  _3(.)  C)  cis low iuentv  h1h mtuiiy  E  Figure 4-1. (a) Schematic of the relationship between electric polarization (F) and electric field (E). (b) Schematic of electronic transitions that give rise to THG.  At high field intensities, the linear relationship breaks down and P is no longer proportional to E (Figure 4-la), and Equation 2 is used to compensate for the small deviations from linearity,  where 12) and  are the quadratic and cubic susceptibility tensors.  =  +  (3)  (1)  )E(a + (2)( ) ; ) 0 2 , ; ) 1 E(a EQ  (2)  1 )E(to 3 )E(a 2 )E(a) )+ 3 ; a 2 a) 0 (—a  A consequence of this nonlinear relationship is harmonic generation, a nonlinear response whereby the material doubles or triples the frequency of the incident light with an intensity that is proportional to the square of 2 and  (3),  respectively. Accordingly, the intensities of these 94  harmonics should increase as the induced polarization (P) increases. In the case of polymeric materials, this may be achieved by extending the effective conjugation lengths along the polymer backbone by improving molecular order or by incorporating transition metals with polarizable d-electrons. Here, we are interested in third harmonic generation (THG), a thirdorder response that is the result of a series of electronic transitions (Figure 4-1 b) induced by the absorption of three photons of frequency o followed by the emission of a single photon of frequency 3u. Conjugated polymers such as polythiophene, polyacetylene, and poly(2,5-dimethoxy-pphenylenevinylene) have excellent NLO properties 47 that have been linked to the degree of bond alternation in these systems. 4 Since the effective conjugation lengths of conducting ’ 8 polymers are influenced by the orientation of the repeat units in the backbone, small improvements in alignment can give rise to large improvements in NLO response.’ 5 For instance, Okawa and co-workers have demonstrated that the uniaxial stretching of polyalkyithiophene films enhances  >•’ 3 6  The authors conclude that the process of stretching  induces both polymer chain alignment and planarity (Figure 4-2) giving rise to films of higher order and enhanced conjugation.  95  sçs,  Stretching --  Figure 4-2. Illustration of main chain orientation before and after stretching.  In addition to mechanical alignment strategies, it is possible to improve the NLO response of a material by modifying the conditions under which it is prepared. For instance, biopolymer 7 phthalocyanines,’ composites,’ ° and polydiacetylenes 82 ’ show enhanced NLO properties when 2 processed under conditions of microgravity. Interestingly, electropolymerization, a facile and effective method to prepare thin films of conjugated polymers for NLO studies, is virtually unexplored in microgravity, despite studies that suggest electrochemical processes are significantly influenced by gravity-driven convection currents. 22 For instance, Gao and co workers have demonstrated that the steady-state voltammetric currents generated from the oxidation and reduction of [Fe(CN) J’ and [Fe(CN) 6 3 respectively, are angularly dependant on J 6 the orientation of the electrode surface with respect to the gravitational field. 23 This seminal work provides indirect evidence that gravity-driven convection currents influence the process of mass transfer at the surface of an electrode.  96  Convection currents are a consequence of density gradients that form as the composition of the fluid at and near the surface of the electrode changes due to reactant consumption, product formation, and the redistribution of counterions during an electrochemical reaction (Figure 4-3). This phenomenon is similar to that observed in the process of crystallization whereby convection currents are generated as a result of solution inhomogeneity and sedimentation that arise after crystal nucleation. 24 Ultimately, these density gradients create buoyancy forces that are expected to influence the structural quality of the electrodeposited material. It is reasonable then to hypothesize that these forces can influence electropolymerization, a process where soluble monomers are oxidatively coupled to form insoluble films with unpredictable degrees of intermolecular order. 25 Performing these experiments in microgravity  (—‘  0 g) may lead to  polymer films with improved morphologies and properties. For instance, Mizuno and co workers have demonstrated that thin films prepared by the electropolymerization of pyrrole in a drop tube are more electrochemically stable compared to those grown under terrestrial conditions  (—  1 g). 26 Furthermore, polypyrrole particles prepared via chemical oxidative  coupling in 0 g were found to be smaller and adopt a different morphology compared to those grown in 1 g. 27  97  tightly adsorbed inner layer  diffuse part of double layer  bulk solution  Figure 4-3. Electric double layer formed as a result of polymerization at the electrode surface.  Note the uneven distribution of product (polymer, red spheres), reactant (monomer, blue spheres) and counterions (electrolyte, +,-).  98  4.1.2  Chapter Objective  Schiff base metal complexes have been studied extensively for their NLO properties. ° 283 Their large NLO response arises from the polarizable d-electrons that are inherent in the metal centres and the significant charge transfer character of the excited states that gives rise to large transition dipole moments. 28 A variety of Schiff base complexes have been electrochemically polymerized to afford hybrid conjugated polymer films that possess catalytic, sensing, and electrochromic properties (see Chapter 1); however, the NLO properties of these films have not been investigated. In this Chapter, the electrochemical polymerization of a series of thiophene-functionalized , Ni 2 Cu , and VO 2 2 Schiff base complexes with peripheral alkoxy substituents under terrestrial and microgravity conditions is reported. The objective of this work is to determine how the metal, pendant alkoxy chains, and gravity influence the third-order NLO response of the thin films. In the case of the latter, it is anticipated that the microscopic order of the films grown in the absence of convection currents will be improved and, as a consequence, larger  xm values  should be observed. ’ 3  99  4.2 4.2.1  EXPERIMENTAL General  Materials and Equipment. Catechol, copper(I) bromide, 2-tributyistannyithiophene, anhydrous dimethylformamide (DMF), 1-bromododecane, bromomethylcyclohexane, sodium methoxide, copper acetylacetonate (acac), vanadyl acetylacetonate, and nickel acetylacetonate tetrahydrate were purchased from Aldrich. ) 3 ( Trans-PdC1 2 PPh was obtained from Strem Chemicals. Tetrahydroffiran (THF) was distilled from sodium and benzophenone under nitrogen gas. Deuterated solvents were purchased from Cambridge Isotope Laboratories, Inc. All purchased chemicals were used without further purification. 5-Thienylsalicylaldehyde 32 (76) and alkoxy substituted diamines 77-79, and 92-93 were prepared according to literature procedures for related compounds. ’ 33  All reactions were performed using standard Schlenk techniques with  dry solvents under a dinitrogen atmosphere. Solution electronic absorption spectra were  obtained in DCM on a Varian Cary 5000 UV-vis-near-IR spectrometer using a 1 cm quartz cuvette. Solid-state absorption spectra were acquired on films electrodeposited onto ITO on glass. JR spectra were obtained directly from samples using a Nicolet 6700 FT-JR spectrophotometer or from KBr dispersions on a Bomem MB- 100 spectrometer. JR spectra were obtained from polymer films poly-MFC , poly-VOC 12 , poly-NiC 12 , and poly-CuC 12 12 using a Hyperion 2000 FT-IR microscope. ‘H and ‘ C NMR spectra were acquired on a Bruker AV-300 3 or AV-400 spectrometer, and spectra were referenced to residual protonated solvent at ö 5.32 for deuterated dichloromethane ) C, 2 (CD 1 ö 2.50 for deuterated dimethylsulfoxide 6 (DMSO-d ) , and 3 7.24 for deuterated chloroform 3 (CDC1 ) . All ‘ C NMR experiments were carried out in CD 3 CI 2 and referenced to 6 54.00. High resolution electrospray (ESI) or electron impact (El) ionization mass spectra and elemental analyses were performed at the UBC Microanalytical Services 100  Laboratory. Scanning electron microscopy (SEM) images were taken using a Hitachi S4700 electron microscope operating at 5 kV. Films were imaged directly on Au/Si electrodes used for electrodeposition. Thin film thicknesses were measured by atomic force microscopy using an Asylum Research Molecular Force Probe 3D instrument. Electrochemistry. Cyclic voltammetry (CV) experiments were conducted using either a Pine AFCBP1 bipotentiostat or an Autolab potentiostat. The working electrode was either a Pt disk, an indium tin oxide (ITO) thin film on glass, or Au (1000 A) deposited on Si using a Cr (50 A) adhesion layer. The counter electrode was a Pt mesh and the reference electrode a silver wire. The scan rate was fixed at 100 mV/s. An internal reference, decamethylferrocene, was added to correct the measured potentials with respect to a saturated calomel electrode (SCE). [(n N]PF was used as a supporting electrolyte and was purified by triple recrystallization from 4 Bu) 6 ethanol and dried at 90 °C under vacuum for 3 days. DCM used for CV was purified by passing the solvent through an activated alumina tower. Electrochemistry in Microgravity. Electrochemical polymerization was carried out in a homebuilt instrument that features four sealed electrochemical cells cut into a Delrin® block, each equipped with three individually-addressable electrodes for electropolymerization experiments. LABView software on a laptop computer enables time- and voltage-controlled electrochemical processes with in situ current measurements. A silver wire (reference electrode), platinum wire (counter electrode) and Au on glass (working electrode) were used. The deposition solution consisted of 1 mM monomer dissolved in dry DCM containing 0.1 M 6 N 4 [(n-Bu) . ]PF Deposition was carried out by electrolysis at 1.5 V vs. a Ag quasi reference electrode for lOs. For polymers grown in microgravity, electropolymerization was initiated manually onboard the Canadian Space Agency’s (CSA) Falcon 20, a commercial jet with 101  modified hydraulic and fuel systems, for the period of 15  —  20s when microgravity conditions  were present during the parabolic flight path. For comparison, polymers were also electropolymerized at 1 g using the same conditions after the plane had landed. All electropolymerized polymers were dedoped by applying a potential of 0 V to the working electrode for 60s. Cabin temperatures were not recorded in the aircraft during polymerization experiments. However, temperature measurements were made using a thermocouple for another set of experiments conducted under similar conditions. These measurements indicated that the temperature of the cabin was only 2 4 C cooler for the polymerization experiments carried out -  under conditions of microgravity than for the experiments conducted on the ground. X-ray Crystallographic Analysis. All x-ray data for structures NiC 12 (91) 12 (90) and CuC were collected on a Bruker X8 APEX diffractometer using Mo-Kc radiation.  Data were  collected at -100.0 ± 0.1 °C in four scan sets using 0.50 oscillations and exposure times of 30 seconds. All data were collected and integrated using the Bruker SAINT 4 software package and corrected for absorption using SADABS. 35 The structures were solved by direct methods. All refinements were performed using the Sl-IELXTL 36 crystallographic software package of Bruker-AXS. Complex 90 (NiC ) crystallizes in the space group P-i with two molecules of 12 ethanol in the asymmetric unit. Both thiophene rings are disordered by rotation about the C4-C5 and C 15-Cl 9 bonds, respectively. The disorder was modelled with constraints on C-S and C-C bond distances. All hydrogen atoms involved in hydrogen-bonding were located in difference maps and refined isotropically, while all other hydrogen atoms were included in calculated positions but not refined. Complex 91 (CuC ) crystallizes in the space group P2 1 12 /c with one molecule of methanol in the asymmetric unit.  All non-hydrogen atoms were refined  anisotropically. All hydrogen atoms involved in hydrogen-bonding were located in difference 102  maps and refined isotropically, while all other hydrogen atoms were included in calculated positions but not refined. Nonlinear Optical Measurements. An amplified Ti:sapphire laser with an output at 800 nm, a pulse duration of 130 fs, and a repetition rate of 1 kHz was used for third harmonic generation (THG) in reflection geometry. The incident beam was p-polarized with an incident angle of 45  .  A series of mirrors, bandpass filters, and a monochromator were used to separate the fundamental 800 nm beam and the THG. The THG intensity was detected by a photomultiplier tube (PMT) and a gated integrator. The energy of the incident laser beam was typically below 3 jtJ per pulse. At this energy level, the THG contributions from air and other optics were found  to be negligible. To compare the THG from the polymer films to the reference silica window, the intensity of THG can be written as 2 J(3))(3)  where  2 xl xI(co)xd 2  (3)  is the effective third-order nonlinear susceptibility, I (a) is the incident beam  intensity, d is the thickness of the film, and l is the coherence length. Using the third-order nonlinear susceptibility of silica, susceptibility of the polymers,  Z  (3)  (3) Zr  x  (3),  x  as the calibration reference, the third-order nonlinear can be derived as  /i  x  d x d 1  (4)  103  where d 3 is the sample thickness and  FR and FR  are the Fresnel factors for silica and the  samples, respectively. The dielectric constants used to determine the Fresnel factors of the polymers were obtained using ellipsometry. With d,. nm, and F = 1.8110 and  FR =0.0356,  =  2 / 2g =127.3 nm, 1 =16.4 nm, 1 =12.6  the third-order nonlinear susceptibilities of the polymers,  were determined using equation (4). 4.2.2  Collaborators  The synthesis and CV studies on complexes 83-88 were performed by Dr. Britta Boden and Dr. Bryan Sih respectively. The homebuilt electrochemical instrument was designed and built in collaboration with the Electronic and Mechanical Shops of the Department of Chemistry at UBC and by Engineering Physics students Edwin Chan, Vivide Chang, and Linus Leung. All x  ray crystallographic analyses were performed by Dr. Brian Patrick. All nonlinear optical measurements were carried out by Dr. Qifeng Li, Dr. Zhenwei Wang, and Prof. Keng C. Chou at UBC. All statistical analyses were performed by Prof. Stan Floresco of the Department of Psychology at UBC. The author’s contributions to this work include: (1) the synthesis and characterization of the novel compounds 82, 89-91, and 94-98, (2) the CV studies on 82, 89-91, 94, 95, and 99, (3) the design, assembly, and maintenance of the homebuilt electrochemical instrument used for the microgravity experiments, (4) all polymer film thickness measurements determined by AFM (5) all electropolymerizations performed in 0 g and 1 g, and (5) IR and UV/vis absorption studies on poly-MF , poly-VOC 12 , poly-NiC 12 , and poly-CuC 12 . The SEM micrographs of poly-1’IFi 12 , 2 , poly-N1C 12 poly-VOC , and poly-CuC12 were taken by both the author and Dr. Bryan Sih. 12  104  The author was also responsible for coordinating the flight campaigns, including logistics for transporting the chemicals and apparatus from Vancouver to Ottawa. Flight campaigns were scheduled in collaboration with John Croll, a research officer at the Flight Mechanics and Avionics NRC Institute for Aerospace Research (JAR) and Timothy Leslie, a supervisor of Flight Operations and pilot. 4.2.3  Synthesis  N, N ‘-4-5-didodecyloxyphenylenebis(5-(2-thienyl))salicylidenimine (MFC ), (82). Under a 12  nitrogen atmosphere, 5-thienylsalicylaldehyde 76 (0.642 g, 3.14 mmol) and 4,5-didodecyloxy1,2-phenylenediamine 79 (0.502 g, 1.05 mmol) were dissolved in anhydrous THF (ca. 40 mL) and heated to reflux overnight. The orange solution was cooled to room temperature and concentrated in vacuo. Addition of cold methanol to the concentrate precipitated an orange solid that was isolated on a Büchner funnel. The product was purified by recrystallization in a chiorofomi/ethanol mixture (0.576 g, 64%). 1 H NIvIR (CDCI , 300 MHz): 3  13.24 (2H, s, OH),  8.64 (2H, s, CH=N), 7.59 (4H, m, aromatic CR), 7.07 (4H, m, aromatic CR), 7.18 (4H, m, aromatic CR), 6.83 (2H, s, aromatic CR) 4.07 (4H, t, 3 Jjq CH 2 OCH ) , 1.49-1.47, (36H, m, CH ), 0.88 (6H, t, 3 2 J  =  =  6.5 Hz, 2 0Cf1 ) , 1.86 (4H, m, 6.8 Hz, ) 3 C 2 -CH H . ‘ C NMR 3  CI 100 MHz): ö 162.2, 161.3, 150.0, 144.2, 135.9, 131.2, 129.9, 128.7, 126.4, 124.5, (CD , 2 122.8, 120.1, 118.3, 105.2, 70.3, 32.5, 30.3, 30.3, 30.0, 29.97, 29.9, 26.7, 23.3, 14.5. UV-vis C: 2 (CH ) I  (a)  N 5 C 6 H S 4 0 2 2 (M 9  =  +  276 (63000), 368 (27000) nm (L mof’cm’). HRMS (ESf): Calcd for  H): 849.4699. Found: 849.4698. JR (KBr): v  =  2920, 2843, 1616, 1507,  1475, 1274, 1169, 807, 678 cm . Mp. 156 °C. Anal. Calcd for 0 1 58 C 6 H : S 2 N 4 2 C, 73.54; H, 8.07; N, 3.30, found: C, 73.50; H, 8.10; N, 3.34.  105  12 (89). The same procedure was used as for the preparation of 90. The product was V0C isolated as a red solid (yield 85%). HRMS (El): Calcd for 2 S 5 C 6 H V N 5 O 2 913.3853. Found 6 913.3859. UV-vis ) C: 2 (CH 1 =  (E)  301 (62000), 442 (24000) nm (L mor’cm’). IR (KBr): v  2924, 2847, 1607, 1519, 1462, 1374, 1265, 1169, 1108, 975, 818, 686, 609, 512 cm . Mp. 1  223 C (dee).  Anal. Calcd for 2 N 5 C 7 H V S 7 0 2 (M 0  +  =  0): C, 65.73; N, 2.95; H, 7.43. 2 2 H  Found: C, 66.01; N, 2.94; H, 7.70. 12 (90). Under a nitrogen atmosphere, pro-ligand 82 (0.101 g, 0.119 mmol) and nickel (II) NiC acetate tetrahydrate (0.090 g, 0.36 1 mmol) were dissolved in anhydrous THF (ca. 30 mL). The dark red solution was left to reflux for 3h. After cooling to room temperature, the solution was concentrated in vacuo. A dark red solid precipitated upon addition of methanol and was isolated using centrifugation. After washing with methanol and hexanes, the product was recrystallized from an ethanol/THF mixture to afford dark red crystals (0.8 10 g, 75%). ‘H NIVLR (CDC1 . 300 3 MHz)  7.95 (2H, s, CHN), 7.52 (4H, m, aromatic Cl]), 7.05 (2H, m, aromatic Cl]), 6.99 (2H,  aromatic Cl]) 4.06 (4H, m, 2 OCH ) , 1.86 (4H, m, ) CH 2 OCH , 1.50-1.25, (36H, m, CH ), 0.86 2 (6H, m, ) 3 C 2 CH H . UV-vis ) C: 2 (CH 1  2max  ()  =  317 (60000), 388 (36000), 507 (16000) nm (L  mor’cm’). FIRMS (El): Calcd for 2 HoS 5 C N N O 2 i: 904.3818. Found: 904.3826. JR (KBr): v =  2923, 2847, 1615, 1515, 1463, 1354, 1277, 1169, 815, 686 cm’. Mp.  Calcd for 5 O 5 C 7 H N S 2 N 3 0 i (M  +  =  225 ‘C (dee). Anal.  EtOH): C, 67.87; H, 7.52; N, 2.99. Found: C, 67.69; H, 7.44;  N, 3.06.  12 (91). The same procedure was used as for the preparation of 90. The product was CuC isolated as a red solid (yield 64%). HRMS (El): Found: 911.3756. UV-vis ) C: 2 (CH 1 (18000) nm (L mof’cm’). JR (KBr): v  (6)  =  =  Calcd for : 56 C 6 H C N 4 O 2 S 2 u 911.3742.  319 (55000), 380 (17000), 425 (17000), 462  2919, 2855, 1607, 1515, 1463, 1374, 1277, 1173, 106  1116, 819, 694 cm . Mp. 1  =  178 °C. Anal. Calcd for H 5u: C C S 2 N 4 O 6 2 C, 68.57; H, 7.30; N,  3.08. Found: C, 68.20; H, 7.38; N, 3.10.  8 (94). Under a nitrogen atmosphere, 5-thienylsalicylaldehyde 76 (0.140 g, 0.68 mmol), CuC 4,5-dioctyloxy- 1 ,2-phenylenediamine 79 (0.100 g, 0.27 mmol), and copper (II) acetylacetonate (0.086 g, 0.33 mmol) were. dissolved in anhydrous THF (ca. 40 mL) and heated to reflux overnight. The red solution was cooled to room temperature and concentrated in vacuo. Addition of cold methanol to the concentrate precipitated a red solid that was isolated by centrifugation. The product was isolated as a waxy red solid (0.186 g, 85%). FIRMS (El): Cald for 4 4 C j 5 H C S 2 N O 4 u (M  +  H): 798.2586 Found: 798.2586. UV-vis ) C: 2 (CH I .  (19500), 425 (19000), 379 (18500), 319 (61000) nm (L moF’cm’). IR: v  =  2max (6)  464  2920, 2852, 1606,  1583, 1515, 1502, 1461, 1375, 1322, 1273, 1168, 1140, 118, 1018, 813, 685, 578, 559, 499 cnf ‘.Mp.  =  210-2 13 C. Anal. Calcd for 5 O 4 C 5 H C S 2 N 2 u (M  +  0): C, 64,72; H, 6.42; N, 3.43. 2 H  Found: C, 64.61; H, 6.10; N, 3.54. 1 (95). The same procedure was used as for the preparation of 94. The product was CuC isolated as a red solid (yield 8 1%). FIRMS (El): Cald for O 55 C 7 H C S 2 N 4 6 u (M Found: 966.4479. UV-vis ) C: 2 (CH I (52000) nm (L moF’ cm’). IR: v  (6)  =  +  H): 966.4464.  460 (167000), 425, (16600), 378, (17000), 319  2917, 2848, 1608, 1581, 1515, 1503, 1460, 1428, 1416,  1373, 1324, 1277, 1265, 1169, 1119, 944, 848, 814, 720, 683 cm’. Mp. Calcd for 6 O 5 C 7 H C S 2 N 6 3 u (M  +  163-165 °C. Anal.  0): C, 67.07; H, 7.84; N, 2.79. Found: C, 67.26; H, 7.46; 2 2H  N, 2.87. 1,2-dicyclohexylmethoxybenzene (96). Sodium hydride (1.64 g, 68.3 mmol) was added portionwise to a solution of catechol (3.00 g, 27.2 mmol) and {Bu N]Br dissolved in dry THF 4 (Ca. 30 mL). After lh of heating to reflux, bromomethylcyclohexane (11.3 mL, 81.6 mmol) was 107  added portion-wise and left to reflux for an additional 48h. Progress of the reaction was monitored by thin-layer chromatography (TLC) (1:2 DCM/hexanes). Once the reaction was complete, the mixture was cooled and diluted with diethylether. The organic phase was washed with water and dried over MgSO . Solvent was removed by reduced pressure techniques to yield 4 an oil that was purified by column chromatography (hexanes:DCM, 2:1). A clear oil was isolated (4.84 g, 56%). 1 H NI\4R 2 CI 400 MHz): 6 6.88 (4H, s, aromatic CH), 3.78 (4H, d, (CD , 6.30 Hz), 1.84 (12H, m, Cl]), 1.22 (IOH, m, Cl]). EI-MS: rn/z = 302 (M). 4,5-dicyclohexylmethoxy-1,2-dinitrobenzene  (97).  A  solution  of  1,2-  dicyclohexylmethoxybenzene 96 (3.23 g, 10.1 mmol) in HNO 3 (ca. 50 mL) was heated to 80 °C for 1 8h. Upon cooling, the yellow mixture was poured into H 0 and a yellow product was 2 isolated using a Btichner funnel. The solid was washed with an aqueous solution of NaHCO 3 and recrystallized from an ethylacetate/ethanol solution to yield a crystalline yellow solid (2.80 C1 400 MHz): 6 7.31 (2H, s, aromatic Cl]), 3.90 (4H, d, (CD , g, 71%). ‘H NMR 2  JHJI 3  5.80  Hz), 1.86 (12H, m, Cl]), 1.22 (1OH, m, Cl]). ‘ C NTv1R , 3 C1 100 MHz): 6 152.8, 136.9, 2 (CD 108.7, 76.0, 38.0, 30.1, 27.0, 26.3. IR: v  =  2925, 2850, 1585, 1513, 1330, 1276, 1225, 1071,  1037, 878, 819, 752, 677 cm’. EI-MS: m/z = 392 (Md). Anal. Calcd for 0 C 2 H : 2 N 6 0 C, 61.21; 8 H, 7.19; N, 7.15. Found: C, 61.24; H, 7.07; N, 7.04.  N,  N’-4-5-dicyclohexylmethoxyphenylenebis(5-(2-thienyl))salicylidenimine  (MFCiecy),  (98). Under a nitrogen atmosphere, a mixture of 4,5-dicyclohexylmethoxy- 1 ,2-dinitrobenzene 97 (200 mg, 0.51 mmol), hydrazine monohydrate (1 mL, 20.60 mmol), and 10 mg of Pd/C in dry THF (ca. 200 mL) was left to reflux for 24h. Rainey nickel (10 mg) was added and the  mixture was stirred for an additional 6h. The mixture was filtered through a Celite pad into a flask containing 5-thienylsalicylaldehyde (260 mg, 1.27 mmol) and left to reflux for 24h. The 108  orange solution was cooled to room temperature and concentrated in vacuo. Addition of cold methanol to the concentrate precipitated an orange solid that was isolated using a Büchner funnel. The product was purified by recrystallization in a chloroformlmethanol mixture (320 mg, 89 %). ‘H NMR 2 C1 400 MHz) 6 13.21 (2H, s, 011), 8.70 (2H, s, CH=N), 7.67 (2H, d, (CD , =  2.2 Hz, aromatic Cl]), 7.63 (2H, dd, 3 Ji-m  (4H, m, aromatic Cl]), 7.08 (2H, t, 3 J  =  =  8.6 Hz,  JHH  =  6.3 Hz, aromatic Cl]), 7.25  4.4 Hz, aromatic CR), 7.03 (2H, d, 11 J,3 1 .  =  8.6 Hz,  aromatic Cl]), 6.88 (2H, s, aromatic Cl]), 3.90 (4H, d, 6.1 Hz, 2 0C11 ) , 1.82 (12H, m, Cl]), 1.27 (1OH, m, Cl]). ‘ C1 100 MHz) 6 162.1, 161.2, 150.3, 144.2, 135.8, 131.2, 129.8, (CD , C NMR 2 3 128.6, 126.4, 124.5, 122.8, 120.1, 118.3, 105.2, 75.7, 38.5, 30.4, 27.2, 26.4. IR: v = 2921, 2851, 1616, 1510, 1483, 1466, 1447, 1282, 1264, 1174, 1079, 1015, 982, 876, 846, 816, 689, 491 cm  Anal. Calcd for 0 C 4 H S 2 N 5 3 (M  +  MeOH): C, 70.08; H, 6.56; N. 3.80. Found: C, 70.20; H,  6.30; N, 3.88. CUCMeCy (99). The same procedure was used as for the preparation of 90. The product was  isolated as a red solid (yield 92%). HRMS (El): Cald for O C 4 H C S 2 N 4 u (M + H): 766.1960. 2 3 Found: 766.1948. UV-vis ) C: 2 (CH I Xm (60000) nm (L moF’cm’). IR: v  =  (E)  =  462 (20000), 428 (19400), 380 (18700), 319  2921, 2848, 1611, 1586, 1513, 1501, 1367, 1273, 1169,  1028, 980, 830, 810, 678, 597 cm . Mp. >220CC. 1  Anal. Calcd for O C 4 H C S 2 N 5 2 4 u (M  +  0): C, 64.30; H, 5.65; N, 3.57. Found: C, 64.63; H, 5.46; N, 3.59. 2 H  109  RESULTS AND DISCUSSION  4.3  Synthesis and Structure of Schiff Base Monomers  4.3.1  5-Thienylsalicylaldehyde 76 was prepared via Stile cross-coupling of 75 with 2tributylstannyithiophene in the presence of a Pd catalyst. The novel metal free (MF) Schiff base , and MFC 6 compounds MF , MFC 0 12 (80-82) were prepared by the Schiff base condensation of  two equivalents of 76 with the appropriate diamine (77-79). The metal complexes were synthesized in moderate yield (65-85%) by reacting the appropriate proligand with the respective metal salt in THF at reflux (Scheme 4-1).  Scheme 4-1 R  R  R 77R=H  —  OHO  \/  OHO  3 Sn(Bu)  ‘  —  \/  -  79 R = OCi _: H 2  2 NH  N 2 H  R  C1 2 ) 3 Pd(PPh  80(MFC R=H ) 0 ) R=0C 6 13 H 6 81 (MFC ) R = 0C 12 25 H 12 82 (MFC  76  75  R  R  O or 2 M(OAC) • riH 2 2 M(acac)  —  >Joxo:bci 83(VOC ) 0 86 (VOC ) 6 89 (V0C ) 12  MVO,RH M  =  VO, R  =  0C 1 H 6 3  M  =  VO, R  =  0C 2 H 12 5  84(NiC ) 0 87 (NiC ) 6 90 (N1C ) 12  M=Ni,R=H M M  =  Ni, R Ni, R  0C 1 H 6 3 =  0C 2 H 12 5  85(CuC ) 0 ) 6 88 (CuC ) 12 91 (CuC  M=Cu,R=H M  =  Cu, R  =  0C 1 H 6 3  M  =  Cu, R  =  0C 2 H 12 5  110  Monomers 89-91 were isolated by centrifugation after precipitating them from the reaction solution with methanol. The dark red waxy solids are (1) soluble in organic solvents that are commonly used for electrochemical experiments, (2) thermally stable with melting points between 178 and 225 °C, and (3) environmentally stable under ambient conditions, as suggested ) that remained unchanged over a three-year 2 by the ‘H NMR spectral features of 90 (NiCi period (see Appendix 6). Crystals suitable for single-crystal XRD studies were grown from ethanollTHF (90, NiC ) or 12 methanol/THF (91, CuC ) mixtures. Compound 90 crystallizes in the centrosymmetric space 12 group P-i with the molecular structure shown in Figure 4-4a. The N, N’-phenylene-salicylidine (saiphen) moiety is essentially flat with a Ni 2 ion coordinated inside the N 0 binding pocket in 2 a square planar geometry. The thiophene rings, which were both modelled with static disorder over 2 sites, are nearly co-planar with the iminophenol rings. In the single crystal, 90 adopts a side-slipped cofacial stacking arrangement with adjacent molecules oriented nearly 1 8O with respect to an axis perpendicular to the plane of the salphen moiety (Figure 4-4b). An interplanar distance of 3.4 A indicates the presence of it-it interactions along the stacking axis where both the thiophene rings and the Ni 2 salphen groups are involved. The alkoxy chains are interdigitated with those from other molecules in the lattice and occupy the space between the it—stacks. Only one alkyl chain is nearly fully extended (see 03, Figure 4-4a) relative to the plane of the diiminobenzene ring while the other alkyl chain is significantly kinked.  111  (a)  S2b  SI b  02  01 Sla  S2a  (b)  --—--V  Figure 4-4. (a) Thermal ellipsoid plot of 90 (NiC ). Thermal ellipsoids are drawn at 50% 12 probability. The hydrogen atoms are omitted for clarity. (b) Packing diagram of 90 with alkoxy chains and hydrogen atoms removed for clarity. 112  Compound 91 (CuC ) crystallizes in a centrosymmetric space group P2 12 /c with the 1 molecules stacked in a cofacial arrangement (Figure 4-5). The Cu 2 ion is in a slightly distorted square planar geometry with a small degree of torsion between the hydroxyphenyl rings. Like 90, compound 91 exhibits intermolecular  it  interactions along the stacking axis where  interplanar separations between adjacent molecules are between 3.3  —  3.4  A. Unlike 90, only  one thiophene ring is nearly coplanar to the iminophenol ring while the other is significantly twisted (torsion angle of Ca. 43 ). The alkoxy chains are nearly fuiiy extended relative to the diiminobenzene ring (Figure 4-5 a) and form an extended interdigitated network with those from adjacent stacks. Overall, it appears that the packing structures of 90 and 91 in the single crystal are significantly influenced by both the strong intermolecular it-interactions between the saiphen moieties and the van der Waals interactions between the extended alkoxy chains, effects that are likely to manifest themselves in the organization of the resulting polymers.  113  (a)  02  01  Figure 4-5. (a) Thermal ellipsoid plot of 91 (CuC ). Thermal ellipsoids are drawn at 50% 12  probability. The hydrogen atoms are omitted for clarity. (b) Packing diagram of 91 with alkoxy chains and hydrogen atoms removed for clarity.  114  4.3.2  Electrochemical Polymerization of Schiff Base Monomers and Film  Characterization  In our preliminary experiments, all polymers were deposited electrochemically at 1 g in order to characterize the films and examine their film quality. These experiments were carried out in either 1 mM (80-82, 86-86, 89-91) or saturated (ca. 0.1 mM) (80 and 83-85) DCM solutions of monomer in sealed glass three-electrode electrochemical cells. All monomers were oxidatively polymerized by sweeping the working electrode between 0 V and the onset of current (+1.5 to +1.75 V vs. SCE) for a total of 10 cycles. During polymerization, an increase in current was  observed upon successive sweeps (see Figure 4-6 for a representative voltammogram and Appendix 6), a feature consistent with previous observations for polymers 32-47 prepared by Swager and co-workers. 37 From visual inspection, it was apparent that most films were stable to multiple washes with DCM while showing little cracking upon drying; however, films prepared from monomers 80 and 83-85 (i.e., those without alkoxy chains) were thin, unstable, and of poor quality. The NLO data for these films will not be discussed herein. The JR absorption data of the monomers 89-91 and their corresponding polymers are listed in Table 4-1. The results suggest that the monomers maintain their structural integrity after polymerization as evidenced by the similarity between the absorption bands.  115  0  0 C  C  0  0  V 0  c 0  0.0  0.2  0.4  0.6  0.8  1.0  1.2  1.4  1.6  1.8  Potential (V) vs SCE Figure 4-6. Cyclic voltammogram of 91 (CuC ) in DCM containing 0.1 M 6 12 N]PF 4 [(n-Bu) .  Scan rate  =  100 mV/s.  Table 4-1. JR absorption peaks of selected Schiff base complexes and their corresponding  polymers. Sample ) 12 89 (V0C  IR absorption (cm’) Sample 2924, 2847, 1607, 1519, 12 poly-VOC 1462, 1347, 1265, 975, 818  IR absorption (cm’) 2928, 2854, 1612, 1508, 1467, 1373, 1276, 985, 835  ) 12 90(NiC  2923, 2847, 1615, 1515, 1463, 1277, 1169, 815  12 poly-N1C  2924, 2853, 1613, 1516, 1467, 1283, 1180, 826  ) 12 91 (CuC  2919, 2855, 1607, 1515, 1463, 1277, 1173, 819  12 poly-CuC  2923, 2851, 1610, 1514, 1467, 1277, 1174, 847  116  The electronic absorption spectra (see Appendix 2 for tabulated data) of monomers 80-91 show an intense band between 280 and 320 nm that is assigned to a ligand-based transition.  ic-it”  At lower energies, multiple absorption bands are observed for the metallated  compounds and are attributed to metal-to-ligand charge transfer transitions that have been observed in other Schiff base complexes. 38 Surprisingly, the metal-free and metallated polymer spectra were found to be similar, suggesting that the metal centres do not extend conjugation across the polymer backbone. Finally, the  ?max  of the polymer films range between 380 and 400  nm, suggesting that absorption is localized in the organic bithiophene linker. This is a reasonable assessment as the  2\max  of 5,5’-bis(4-hydroxyphenyl)-2,2’-bithiophene is 386 nm. 39  SEM micrographs of poly-MFC , poly-NiC 12 , poly-VOC 12 , and poly-CuC 12 12 films deposited onto gold on silicon wafers were taken in order to determine if the metal centre influences film morphology. It appears from Figure 4-7a that the metal-free polymer has the smoothest surface. This is in contrast to the cauliflower-like surface observed on a film of poly-CuC 12 (Figure 47d), a morphology consistent with poly-CuC , PT, and poly-20. The surface of a poly-NiC 6 12 film appears to have a web-like morphology (Figure 4-7c) that is consistent with poly-NiC . 6 Finally, while poly-VOC 12 (Figure 4-7b) appears to have a cauliflower-like surface morphology, poly-VOC 6 has a morphology that is unique amongst these films, rendering the results of this study inconclusive.  117  Figure 4-7. SEM micrographs of(a) poly-MFC , (b) poly-VOC 12 , (c) poly-NiC 12 , and (d) 12  12 electrochemically grown films on gold on silicon wafers. poly-CuC  4.3.3  Electropolymerization in Microgravity  Electropolymerization experiments in microgravity were performed onboard the Falcon 20, a commercial jet with modified hydraulic and fuel systems operated by the Canadian Space Agency (Figure 4-8a). During a typical flight, the jet follows a parabolic trajectory (Figure 4-8b) that includes a free fall drop for Ca. 15s, simulating microgravity (Figure 4-8c). This is followed by a 2 g pullout after which the aircraft is stabilized in order to prepare for another set of experiments. 118  Figure 4-8. (a) Photograph of the Falcon 20. (b) Illustration of parabolic trajectory. (c) The author onboard the Falcon 20 in microgravity. The electropolymerization experiments were carried out in a home-built computer-controlled instrument that features four sealed air-tight electrochemical cells, each equipped with a platinum counter electrode, a silver reference electrode, and three individually-addressable working electrodes prepared by depositing Au (100 nm) on glass with a Cr adhesion layer (20 nm) (Figure 4-9a). A photograph of the instrument is shown in Figure 4-9b. Prior to flight, the electrochemical cells were injected with a solution of monomer (1 mM) and electrolyte ({(n N]PF 0.1 M) in dry DCM. Once microgravity was achieved, the electrochemical cells 4 Bu) , 6 were activated by a trigger and electrodeposition was carried out via electrolysis at 1.5 V vs. Ag quasi reference electrode for 10 s. For comparison, polymers were also electropolymerized at 1  119  g under identical conditions immediately after landing. All polymers were undoped by applying a potential of 0 V to the working electrode for 60 s.  (a) I  counter electrode (Pt wire)  working electrode (Au on glass)  flZ  Z’  c  ZE  c  reference electrode (Ag wire)  ZD  cE  ZZ  (b)  Figure 4-9. (a) Schematic and (b) photograph of the electrochemical instrument.  120  4.3.4  NLO Properties of Schiff Base-Containing Polymer films  The thickness corrected third-order susceptibilities,  of the polymer films prepared over a  4-year period are plotted in Figure 4-10 (see Appendix 4 for tabulated data). Each data point represents a single polymer film that was grown in 1 g (blue circle) or 0 g (red square). The error bars (%-error) account for the THG signal variation across each sample that was measured in Ca. 6 positions and the signal variation associated with the reference, a silica window. Other sources of error include thickness variation across the sample and variation in the size of the working electrode. There are many trends that emerge from the data. Apart from the polymers coordinating VO 2 ions, the metal-containing polymers generally show a larger third-order susceptibility compared to the metal-free polymers. This is likely due to the Ni 2 and Cu 2 metal centres that are involved in both the intramolecular charge transfer transitions with the ligand and rigidification of the saiphen moiety that should enhance the planarity of the polymer backbone. The low thirdorder response of the VO2+ polymers was not surprising, as Gradmaru and co-workers have .  observed lower second-order NLO responses in a VO 2 Schiff base complex compared to the 2 and Cu Ni 2 analogues. 40 Furthermore, it is apparent that the Cu 2 polymers generally show larger  2 polymers. Ledoux and co-workers have also observed this trend values than the Ni  when studying the second-order NLO properties of metallated Schiff base complexes. Using a combination of theoretical and experimental results, the authors conclude that the enhancement in the Cu 2 complexes is a result of its open shell electronic configuration. Cobalt (II) complexes were also found to exhibit larger second-order NLO responses than Ni 2 analogues lending further support to this conclusion. ’ 4  121  10 3.5x10 10 3.0x10  • •  Microgravity (0 g) Terrestrial (1 g)  10 2.5x10 10 x 2.0x10 (esu) 10 1.5x10 10 1.0x10 I  11 5.0x10  ii 0.0-  I  Sample  >  z  c o  >  o  0_  Figure 4-10. Third-order susceptibility  z  >  _‘  0 0-  0  Q  0 0.  -  0.  >% -  0.  0 0-  -  of metallated Schiff base polymers electrodeposited  in microgravity (0 g, red squares) and in 1 g (blue circles).  Another interesting trend is that the metal free salphen polymers poly-MFC 6 and poly-MFC 12 show no enhancement in  when the films are grown in microgravity. This is not the case for  the metallated polymer films that show varying degrees of improvement compared to those grown in 1 g. Interestingly, the effect of microgravity on  is most pronounced for the  polymers possessing dodecyloxy chains. This data suggests that longer alkoxy chains exert a greater influence on polymer packing in microgravity where convection currents are suppressed, 122  affording films of higher microscopic order and enhanced  responses. This rationalization is  sensible, as improvements in the molecular packing of both PATs and alkyl functionalized oligothiophenes have been observed as a result of alkyl-chain interdigitation, 42 a feature that is also present in the single-crystal packing motifs of both 90 and 91. To investigate the role of alkoxy substituents in greater detail, three additional Cu 2 monomers were prepared. Monomers 94 (CuC ) and 95 (CuC 8 ) were synthesized via a one-pot 14 metal-templated Schiff base condensation reaction shown in Scheme 4-2. A third monomer containing cyclohexylmethoxy substituents was also prepared in order to determine if improved order due to microgravity was limited largely to polymers containing linear alkoxy subsitituents. The synthetic route to monomer 99  (CUCMeCy)  is given in Scheme 4-3.  Scheme 4-2 R  R  OHO  —  Cu (acac) 2 +  76  H : 2 NH 2  92 R = 0C 17 H 8 28 H 14 93 R = 0C  94 8 (CuC ) 95 (Cu ) 14 C  M  =  M  =  Cu, R Cu, R  = =  0C 1 H 8 7 28 H 14 0C  123  Scheme 4-3  HO  OH  1) NaH,  R  RR  R  3 HNO N 2 0  96 R=0C 1 H 7 4 =  2 NO  I 1) hydrazine, Pd/C  I  97  1  o RR  Cu (acac)2  2)76  R  R  N  N  [_doH HOb__(jJ  99 (CUCey)  M  =  Cu, R  =  98 (MFCMeCy)  0C 1 H 7 4  The thickness corrected third-order susceptibilities,  M  =  Cu, R  =  0C 1 H 7 4  of the Cu 2 polymer films including  those in Figure 4-10 are plotted in Figure 4-11. The data clearly shows a trend whereby the Cu 2 polymer films grown in 0 g exhibit larger  values compared to those grown in 1 g, including  the polymers with tethered cyclohexylmethoxy substituents. In addition, it is clear from the plot that the effect of microgravity on Cu 2 polymer films with longer alkoxy substitutents is more pronounced save poly-Cu , suggesting that 14  may be optimized by varying the length of the  alkoxy chains.  124  ° 1 3.5x10  ° 1 3.0x10  ° 1 2.5x10 (3)  -  -  s •  Microgravity (0 g) Terrestrial (1 g)  -  10 2.0x10  (esu) 10 1.5x10  10 1.0x10 5.ox1:  Sample  9  9  0  -  o  0  0  -  -  Q-  Figure 4-11. Third-order susceptibility  C)  0-  0.  of Cu 2 Schiff base polymers electrodeposited in  microgravity (0 g, red squares) and in 1 g (blue circles).  A statistical analysis was carried out on the data collected from poly-NiC , poly-CuCMecy, 12 , poly-CuCi 8 poly-CuC , and poly-CuC 2 . Multiple one-way ANOVA’s (Analysis Of Variance) 14  were conducted comparing the  3)  values and there associated %-errors between films grown  under 0 g and 1 g conditions (see Appendix 5). The analyses revealed statistically significant improvements in  3)  for each of these polymers grown in 0 g (all F’s  >  7.19, p<0.05) 43  indicating improvements in microscopic order. ’ Furthermore, the analyses revealed no 3 125  significant difference in the %-errors associated with the  x measurements (save  14 poly-CuC  where the %-error was greater for films grown under conditions of microgravity). These results indicate that apart from poly-CuCi , the absence of gravity driven convection currents has little 4 effect on the THG signal variation of the electrodeposited films. To ascertain whether the orientation of the electrochemical cell influences  12 poly-CuC  films were electrodeposited onto working electrodes in three different orientations relative to the gravitational field (i.e., 0°,  900,  and 1800). The results of this study (Figure 4-12) suggest that if  the orientation of the polymer chains with respect to the substrate surface is influenced by the orientation of the electrochemical cell, there is little effect on  2.4x1O’° QO  180°  10 2.1x10 ° 1 1.8x10  fl  90°  I I I I  \  1.5x1O°  X  (3) 10 1.2x10  (esu) 11 9.0x10 11 6.0x10 1 3.Ox1O I  I  •  I  •  I  C,’  Sample  Ci  .5  0.  9  C?  0  0  0.  0.  Figure 4-12. Third-order susceptibility 3 12 Schiff base polymers electro X of poly-CuC deposited onto working electrodes at 00, 900, and 1800 relative to the gravitational field.  126  4.4  CONCLUSION  A series of metallated Schiff base-containing monomers was electrochemically polymerized under terrestrial and microgravity conditions and the third-order nonlinear optical properties of the subsequent polymer films studied. Monomers that did not possess peripheral alkoxy substituents were poorly soluble in DCM and afforded electrodeposited films of poor quality. Metallated  polymers  with  alkoxy  substituents  generally  showed  larger  third-order  susceptibilities than the analogous metal-free polymers with (3) values increasing in the order of polymers coordinating VO , Ni 2  2+,  2 ions. An enhancement in THG was observed from and Cu  the metallated polymer films grown in microgravity where gravity-driven convection currents are suppressed, suggesting that electrochemically generated buoyancy forces that arise under terrestrial conditions disrupt the weak van der Waals and  n-it  interactions that may exist  between polymer chains and thus ultimately affect the microscopic order of the polymer film. Moreover, the enhancements of (3) were also found to vary with the length of the alkoxy substituents thus confirming their role on the microscopic order of the polymer film electrodeposited in microgravity. Although other contributing factors may influence the results of our studies (i.e., current density, cell vibration, and ionic strength), the small difference in cabin temperature (ca. 2C to 4°C) between microgravity and terrestrial environments suggests that temperature is not a major contributor to the observed  enhancements. Further control  experiments are underway in order to address these issues.  127  4.5 1.  REFERENCES Stegeman, G. I.; Assanto, G., Optical Engineering (New York) 2000, 66, (Integrated  Optical Circuits and Components), 381-418. 2.  Munn, R. W., Princzles and Applications of Nonlinear Optical Materials. Blackie  Academic and Professional: Boca Raton, Fla, 1993; p 5-20. 3.  Gubler, U.; Concilio, S.; Bosshard, C.; Biaggio, I.; Gunter, P.; Martin, R. E.; Edelmann,  M. J.; Wytko, J. A.; Diederich, F., Appl. Phys. Lett. 2002, 81, 2322-2324. 4.  Nalwa, H. S., Miyata, S., Nonlinear Optics of Organic Molecules and Polymers. CRC  Press: Boca Raton, 1997. 5.  Prasad, P. N., Williams, D.J., Introduction to Nonlinear Optical Effects in Molecules and  Polymers. New York, NY, 1990. 6.  Drury, M. R., Solid State Commun. 1988, 68, 4 17-420.  7.  Kajzar, F.; Etemad, S.; Baker, G. L.; Messier, J., Solid State Commun. 1987, 63, 1113-  1117. 8.  Gorman, C. B.; Marder, S. R., Proc. Nati. Acad. Sci. U S. A. 1993, 90, 11297-11301.  9.  Gorman, C. B.; Marder, S. R., Chem. Mater. 1995, 7, 2 15-220.  10.  Cross, G. H., Princzples and Application of Nonlinear Optical Properties. Blackie  Academic and Professional: Boca Raton, Fla, 1993; p 189-225. 11.  Dorsinville, R.; Yang, L.; Alfano, R. R.; Zamboni, R.; Danieli, R.; Ruani, G.; Taliani,  C., Opt. Lett. 1989, 14, 1321-1323.  12.  Heeger, A. J.; Moses, D.; Sinclair, M., Synth. Met. 1986, 15, 95-104.  13.  Schrof, W.; Andreaus, R.; Mohwald, H.; Rozouvan, S.; Belov, V.; Van Keuren, E.;  Wakebe, T., MCLC S&1 Section B: Nonlinear Optics 1999, 22, 295-300. 128  14.  Kaino, T.; Kobayashi, H.; Kubodera, K.; Kurihara, T.; Saito, S.; Tsutsui, T.; Tokito, S.,  Appi. Phys. Lett. 1989, 54, 1619-1621. 15.  Wada, T.; Wang, L.; Okawa, H.; Masuda, T.; Tabata, M.; Wan, M.; Kakimoto, M.-A.;  Imai, Y.; Sasabe, H., Mo!. Cryst. Liq. Cryst. Sci. Tech. 1997, 294, 245-250. 16.  Okawa, H.; Wada, T.; Sasabe, H., Mater. Res. Soc. Symp. Proc. 1992, 244, (Optical  Waveguide Materials), 263-268. 17.  Trantolo, D. J.; Gresser, J. D.; Hsu, Y. Y.; White, R. L.; Wise, D. L., AlP Conf Proc.  1998, 420, 749-754. 18.  Debe, M. K.; Kam, K. K., Thin Solid Films 1990, 186, 289-325.  19.  Debe, M. K.; Poirier, R. J., Thin Solid Films 1990, 186, 327-347.  20.  Debe, M. K.; Poirier, R. J.; Erickson, D. D.; Tommet, T. N.; Field, D. R.; White, K. M.,  Thin Solid Films 1990, 186, 257-288. 21.  Carswell, W. E.; Paley, M. S.; Frazier, D. 0., Polym. Prepr. 2000,41, 1068-1069.  22.  Bard, A. J., Faulkner, L.R., Electrochemical Methods. Wiley: New York, 1980; p 263.  23.  Gao, X.; Lee, J.; White, H. S., Anal. Chem. 1995, 67, 1541-1545.  24.  Vergara, A.; Lorber, B.; Zagari, A.; Giege, R., Acta Cryst. 2003, D59, 2-15.  25.  Fichou, D., Ziegler, C., Handbook of Oligo- and Polythiophenes. Weinheim, 1999; p  183. 26.  Mizuno, M., Jpn. Soc. Microgravity App!. (JASMA) 1996, 13, 239-245.  27.  Nakamura, T.; Akutagawa, T.; Hasegawa, T.; Kikukawa, T.; Araiso, T.; Higuchi, M.;  Hiratani, K., Synth. Met. 1999, 101, 78-79. 28.  Lacroix, P. G., Eur. J Inorg. Chem. 2001, (2), 339-348.  29.  Lacroix, P. G.; Di Bella, S.; Ledoux, I., Chem. Mater. 1996, 8, 54 1-545. 129  30.  Di Bella, S., Chem. Soc. Rev. 2001, 30, 355-366.  31.  Rau, 1.; Armatys, P.; Chollet, P.-A.; Kajzar, F.; Zamboni, R., Mol. Cryst. Liq. Cryst.  2006, 446, 23-45. 32.  Kingsborough, R. P.; Swager, T. M., Adv. Mater. 1998, 10, 1100-1104.  33.  Antonisse, M. M. G.; Snellink-Rueel, B. H. M.; Yigit, I.; Engbersen, J. F. J.; Reinhoudt,  D. N., I Org. Chem. 1997, 62, 9034-903 8. 34.  Kim, D.-H.; Choi, M. J.; Chang, S.-K., Bull. Korean Chem. Soc. 2000, 21, 145-147.  35.  Shen, Y. R., The Princzples ofNonlinear Optics. Wiley: Hoboken, NJ, 2003.  36.  SHEIXJ’L, 5.1; Bruker AXS Inc.: Madison, Wisconsin, USA, 1997.  37.  Kingsborough, R. P.; Swager, T. M., I Am. Chem. Soc. 1999, 121, 8825-8834.  38.  Lever, A. B. P., Inorganic Electronic Spectroscopy. Elsevier: New York. NY, 1984.  39.  Hock, J.; Cargill Thompson, A. M. W.; McCleverty, J. A.; Ward, M. D., I Chem. Soc.,  Dalton Trans. 1996, 22, 4257-4263.  40.  Gradinaru, J.; Fomi, A.; Druta, V.; Tessore, F.; Zecchin, S.; Quici, S.; Garbalau, N.,  Inorg. Chem. 2007,46, 884-895. 41.  Ledoux, I.; Zyss, J., Pure App!. Opt. 1996, 5, 603-612.  42.  Prosa, T. J.; Winokur, M. J.; McCullough, R. D., Macromolecules 1996, 29, 3654-3656.  43.  F is the ratio of the variance of the group means (0 g vs 1 g) to the mean of the “within  group” variances and p is the probability of a Type I error. A Type 1 error is the chance of accepting the research hypothesis (i.e. gravity influences THG) when the null hypothesis is true.  130  CHAPTER 5 Electropolymerized  Pd-Containing  Thiophene  Polymers:  Heterogeneous Catalysts for Cross-Coupling Reactions*  5.1  INTRODUCTION  Palladium is one of the most utilized and versatile transition metals in modern synthetic organic chemistry, and a large number of transformations involve this noble metal as a catalyst or organometallic reagent.’ Examples include the Suzuki, ’ 2  35 and Sonogashira Heck, ’ 3  6  reactions that employ a Pd-catalyst to mediate a variety of C-C cross-coupling transformations (Figure 5-1). As the chemical industry adopts Pd-based processes in manufacturing, 7 demands for ecologically friendly transformations warrant catalysts that are high yielding, separable, recoverable, and reusable. One strategy is to chemically anchor the catalyst to an inert support; 8 10  however, this is often a labour-intensive process where contamination by leaching of the  metal species is always a concern.’ Electrochemically polymerizing oligothiophene-containing Pd-complexes onto inert electrodes has been conducted previously’ 5 and is a promising ’ 2 approach to the development of heterogeneous catalysts, as this facile process avoids the multi step synthetic pathways that are required to introduce substrate anchoring sites and spacers to the polymer backbone.  A version of this chapter has been published. Albano, V. G.; Bandini, M.; Moorlag, C,; Piccinelli, F.; Pietrangelo, A.; Tommasi, A.; S.; Urnani-Ronchi, Wolf, M. 0. Organometallics (Communication); 2007. 26, 4373-4375.  131  (a) Suzuki Coupling 4 ) 3 Pd(PPh B—_)—2 (HO)  +  CO 2 Na 3  —_—4_?  (b) Heck Coupling 2 PdCI —  O  +  , DMF 3 KCO  (C) Sonogashira Coupling  +  H--Q  ::  Figure 5-1. Examples of Pd-mediated cross-coupling reactions.  In addition, the versatility of this process can afford polymers with varying architectures (i.e., Type I, II, and III) that may be modified to optimize the catalytic properties of the films. Thiophene functionalized bipyridine ligands have been previously suggested as potential precursors of polymeric heterogeneous catalysts, though electrochemical homo- and copolymerisation of these systems was unsuccessful.’ 6 Liobet and co-workers have attached Pdcatalysts as pendant groups onto polypyrrole modified electrodes;’ 7 however, the incorporation of the metal centre directly into the polymer backbone has not been explored. In this chapter, a novel approach to the development of ecologically-friendly reusable heterogeneous  organometallic  catalysts  is  presented.  The  electropolymerization  and  characterization of Pd-containing polymers with architectures that are structurally similar to the  132  Type I and II materials covered in Chapter 1 is discussed. These polymers were found to catalyze Suzuki, Sonogashira, and both intra- and intermolecular Heck cross-coupling reactions.  5.2 5.2.1  EXPERIMENTAL General  All reagents used for catalytic studies were purchased from Aldrich Inc. and used without further purification. All reactions were performed using standard Schienk techniques with dry solvents under a nitrogen atmosphere. Solution electronic absorption spectra were obtained in DCM on a Varian Cary 5000 UV-vis-near-IR spectrometer using a 1 cm quartz cuvette. Solidstate absorption spectra were acquired on films electrodeposited onto ITO on glass. Fluorescence spectra were obtained in DCM on a Photon Technology International QuantaMaster fluorimeter using a 1 cm quartz cuvette. GC-MS spectra were taken by El ionization on a Hewlett-Packard 5971 instrument equipped with GC injection. Analytical high performance liquid chromatography (HPLC) was performed on a liquid chromatograph equipped with a variable wavelength detector (deuterium lamp 190-600 nm), using a Daicel ChiracelTM OJ column (0.46 cm I.D. x 25 cm) (Daicel Inc.). X-ray photoelectron spectroscopy (XPS) analysis was performed on a Leybold MAX200 equipped with an Al Kct source with a pass energy of 192 eV. Electrochemistry. Cyclic voltammetry experiments were conducted using an Autolab potentiostat or a Pine AFCBP 1 bipotentio stat. The working electrode was either a Pt disk, an indium tin oxide (ITO) thin film on glass, or Toray carbon paper (TGP-H-030). The counter electrode was a Pt mesh and the reference electrode a silver wire. An internal reference, decamethylferrocene, was added to correct the measured potentials with respect to a saturated 133  calomel electrode (SCE). 6 N]PF was used as a supporting electrolyte and was purified 4 [(n-Bu) by triple recrystallization from ethanol and dried at 90 °C under vacuum for 3 days. All experiments were carried out using a scan rate of 100 mV/s for a total of ten cycles. DCM used for CV measurements was purified by passing the solvent through an activated alumina tower. Typical reaction procedure for Heck reaction using poly-100. A two-neck 10 mL round-  bottom flask equipped with a condenser was charged with a 4 mL mixture of toluene:acetonitrile (1:1), 18 tL of iodobenzene 108 (0.14 mmol), 50 j.tL of ethyl acrylate 109 (0.55 mmol), and freshly distilled triethylamine (TEA) (38 jiL, 0.28 mmol). The modified  electrode (content of [Pd] about 1% respect to iodobenzene) was then introduced in the flask and the solution was refluxed overnight without stirring. An aliquot of the solution was drawn and analysed by GC (cony. 87%). GC-MS (mlz): 77 (35), 103 (60), 131 (100), 162 (60). Typical reaction procedure for intramolecular Heck reaction using poiy-iOO. A two-neck  10 mL round-bottom flask equipped with a condenser was charged with 1  mL of  dimethylacetamide (DMA), 2-iodoanilide 111 (17 mg, 0.05 mmol), and diisopropylethylamine (DIPEA) (17 jit, 0.lmmol). The modified electrode (content of [Pd] about 3% with respect to the iodo compound) was then introduced in the flask and the solution was heated to 80 C for 48h. Progress of the reaction was monitored by TLC and HPLC. Once the reaction was complete, the mixture was diluted with diethyl ether and washed with saturated sodium bicarbonate, NaHCO . The organic layer was washed with brine, dried over sodium sulfate 3 SO and concentrated by removing solvent under reduced pressure. The crude product was 2 (Na ) 4 purified by flash chromatography using a hexanes:ethylacetate (8:2) solvent mixture as the eluent and isolated as a viscous oil (yield 57%). ESI-MS: 188 (M CDC1 ) 3 ; ö 1.51 (3H, s), 3.23 (3H, s), 5.12 (1H, d, 3 Jm  =  +  1). 1 H NMR (200 MHz,  7.8 Hz), 5.19 (1H, s), 5.97 (1H, dd, 134  =  10.8 Hz, 3 Jm  17.2 Hz), 6.87 (1H, d,  JHJ{ 3  =  7.4 Hz), 7.06-7.35 (3H, m). The ee of the  product (0%) was determined by chiral HPLC (Chiralcel OJ: isopropyl alchohol:n-hexanes 5:95, 0.5 mL/min flow, 220 nm, R: 17.1 mm.; R: 18.5 mm.). Typical reaction procedure for Suzuki reaction using poly-100. A two-neck 10 rnL roundbottom flask equipped with a condenser was charged with a 6 mL mixture of toluene:rriethanol (2:1), 40 1 iL of 2-fluoro-iodobenzene 103 (0.34 mmol), 83 mg of phenylboronic acid 104 (0.68 mmol), and potassium carbonate, K 3 C 2 0 (145 mg, 0.68 mmol). The modified electrode (content of [Pd] about 0.5% with respect to iodoarene) was then introduced in the flask and the solution was heated to reflux overnight without stirring. After 40h an aliquot of the solution was drawn and analysed by GC (cony. 91%). GC-MS (m/z): 51(8), 63 (7), 75 (10), 85 (13), 133 (14), 171 (40), 172 (100). Note: all catalytic reactions using poiy-102 were carried out on the same scale and the reaction solutions analysed by GC. Typical reaction procedure for Sonogashira reaction using poiy-iOO. A two-neck 10 mL round-bottom flask equipped with a condenser was charged with 151 j.tL of freshly distilled triethylarnine, 37 tL of phenylacetylene 106 (0.34 mmol), 80 j.tL of 103 (0.68 mmol). The modified electrode (content of [Pd] about 0.5% with respect to iodoarene) was then introduced in the flask and the solution was heated to 80 °C for the specified time without stirring. The reaction conversion was determined by GC-MS by drawing an aliquot of the reaction mixture. GC-MS (mlz): 51(3), 75 (8), 85 (10), 98 (15), 144 (9), 170 (18), 175 (15), 196(100).  135  5.2.2  Collaborators  This project was done in collaboration with Prof. Marco Bandini, Prof. Achille Umani Ronchi, Vincenzo G. Albano, Fabio Piccinelli, and Simona Tommasi at the University of Bologna, who synthesized monomers 100-102 and performed all catalytic studies using poiy 100 and poiy-iOi. The author’s contribution to this work include  (1) the CV studies of  monomers 100-102 (2) preparation of polymer thin films for all catalytic studies, and (3) TJV/vis and XPS spectroscopic studies of 100 and poly-100.  -  136  5.3  RESULTS AND DISCUSSION  Recent findings on the use of chiral diamino-oligothiophenes as versatile ligands for ’ 8 catalysts’  19  has warranted further investigation into the catalytic activity of analogous  polymeric systems grown via electrochemical polymerization. In this study, the monomers (100102, Chart 5-1) possess the same catalytically active Pd-renter; however, they differ with respect to their position relative to the oligothiophene unit(s).  Chart 5-1  cI:H;Pd_  100  101  102  137  All monomers were oxidatively polymerized by sweeping the working electrode between 0 V and +1 to +1.7 V vs. SCE fora total of 10 cycles. These experiments were carried out in 1 mM  DCM solutions of monomer and 0.1 M electrolyte ) 6 N 4 ([n-Bu ]PF in sealed glass three-electrode electrochemical cells. A typical electrochemical polymerization of 100 is shown in Figure 5-2a. The first scan is characterized by the onset of monomer oxidation at ±0.92 V and reaches a maximum at +1.08 V. This is followed by an associated weak reduction process at +0.95 V on the return sweep. Repeated cycling gave rise to a second broad redox wave at lower potentials that is attributed to the electrodeposited polymer. The CV trace of 101 (Figure 5-2b) is nearly identical apart from the distinct shift in monomer oxidation to a higher potential, a feature that may be a consequence of the connectivity between the Pd-complex and the oligothiophene units (i.e., a-connectivity vs f3-connectivity). The CV trace of 102 (Figure 5-2c) also exhibits similar features to that of 100 and 101; however, redox wave growth appeared to plateau after only a few cycles during which time the eiectrochemical solution turned green. Upon further visual inspection, it was apparent that there was very little film growth on the surface of the Pt-disc working electrode. Multiple attempts using different working electrodes (i.e., ITO thin film on glass, Toray carbon paper) and higher monomer concentrations (i.e., 0.2 mM) yielded the same results, suggesting that either (1) oxidative coupling between monomeric units was sluggish on the CV time scale, (2) the polymer is soluble such that deposition does not occur, or (3) the polymer does not adhere to the working electrode, all of which could explain the lack of polymer deposition.  138  C.)  0  C  C D  C)  C) C  0.2  0.4  0.6  0.8  1.0  1.2  1.4  1.6  1.8  Potential (V) vs SCE Figure 5-2. Cyclic voltammograms of(a) 100, (b) 101, and (c) 102 in DCM containing 0.1 M [(n-Bu N 4 . 6 ]PF ) Scan rate = 100 mV/s.  Electrochemically polymerized films of poly-iOO were characterized by UV/vis spectroscopy and X-ray photoelectron spectroscopy (XPS). XPS analysis shows a Pd:S ratio of 1:5.8 (Table 5-1), similar to the ratio obtained from the monomer 100 cast from solution (1:5.0). The Pd 3d 512 peak appears at 338.5 eV, and is consistent with the presence of Pd 2 in similar coordination 20 environment s. UV-vis spectroscopy shows a slight red-shift in the absorption spectrum of poly-lOO (2  =  384 nm) compared to that of 100 which exhibits a  max  at 360 nm that is  consistent with terthiophene. ’ 2 139  11  300  350  400  450  500  550  600  650  700  Wavelength (nm) Figure 5-3. Normalized solution phase UVIvis absorption spectra of 100 (solid line) and poiy 100 (dashed line) at ca. 25 °C.  Table 5-1. XPS analysis of poly-100. Sample 100 poly-100 (before Suzuki reaction) poly-100 (after Suzuki reaction)  Element Pd 3d 512 S2s Pd 3d 2 , 5 S 2s Pd 3d 52 S 2s  Binding Energy (eV)a 338.4 164.9 338.5 164.7 337.8 164.6  Atomic ratio relative to Pd  —  -  1 5 1 5.8 1 6.3  140  A  poly-lOO  film was used as the catalyst in the Suzuki cross-coupling reaction between 2-  fluoro- 1 -iodobenzene 103 and phenylboronic acid 104 under basic conditions ) 3 C 2 (K . 0 After 40h at 80 °C, 91% conversion (by GC) of the desired cross-coupled biaryl 105 was achieved (Scheme 5-la). XPS analysis of the modified electrode after catalysis showed a Pd:S ratio of 1:6.3 (Table 5-1) and minimal change in the Pd 3d 512 binding energy. This is consistent with negligible loss of Pd 2 from the polymer backbone. The signal intensities for the Pd and S peaks are comparable before and after catalysis, indicating that overall loss of fnetallopolymer from  the support is small, Scheme 5-1’ +  (a) 91%  104  103  105  81%  106  103  107 III  +  108 (d)I  87%  110  109 0  iv 57%  111  (÷!)-1 12  a  Reagents and conditions: (i) poly-100, 3 C0 toluene, methanol. 80 °C, 24h; poly-lOO, TEA 2 K , (3 equiv), 70 °C; (iii) poly-lOO, TEA, toluene, acetonitrile, reflux, 24h; poly-IOO, DIPEA, DMA, 80 °C, 48h. 141  In order to ascertain whether the catalysis is authentic ally heterogeneous, aliquots of the reaction mixture were removed from a Suzuki react ion run to completion from which the catalyst film had been removed and a fresh 3 103/100 C 2 4/K mixture added. In this case, the formation of only trace 105 was observed (7% conversion, 48h reflux). This demonstrates that negligible activity results from leaching of catalyst from the substrate surface and that the catalysis is heterogeneous. Moreover, control experiments with 100 in solution (loading 1 mol %, 80 °C, 40 h, conversion 98%) and with the unm odified electrode (80 °C, 40 h, trace conversion) showed that the support neither significa ntly affects the activity of the electrodeposited polymer nor participates in the catalysis. The reusability of the catalyst was tested by removing the electrode from solution, washing with methanol, followed by drying under vacuum. This simple procedure allowed five consecutive Suzuki reactions (103 + 104 —il05) to be carri ed out in high conversions (89-98%). The Sonogashira cross-coupling of 103 with phenylace tylene 106 under copper ligand-free, phosphine ligand-free, and solvent-free conditions in the presence of poly-100 was successful (8 1%, 24 h, Scheme 5-Ib). Good reaction conversion was also obtained in the Heck coupling of iodobenzene 108 and ethyl acrylate 109 (Scheme 5-ic) . The use of excess TEA as a scavenger resulted in 87% conversion after 24h. Moreover, the intra molecular Heck reaction involving (E)-a,-unsaturated 2-haloanilides 111 also proceeded in the presence of a poly-100 film, with racemic oxindole 112 obtained chemoselectively in 57% isolated yield after 48h at 80 °C (Scheme 5-id).  142  Films of poiy-iOi were used as the catalyst in a variety of Suzuki reactions in order to investigate its scope (Scheme 5-2).  Scheme 52a 0  (a)  0 +  ir  6(0 H) 2  Br  89%  113  c::•_Jcf_lLCF3  114  104  B(0H) +  II  I-i  98%  104  115  115 Br  (c) óB(OH)2  50%  115  116  117  (d) CN B(0H) iv +  118  Br  119  93%  120  a  Reagents and conditions: (i) poly-lOl, 3 C0 toluene, methanol, reflux, 48h; poly-lOl, (ii) 2 K , poly-lOl, 3 C0 toluene, methanol, reflux, 48h (iii) ) poly-lOl, 3 2 K , C0 toluene, methanol, 2 K , reflux, 24h, (iv) ) poly-1O1, 3 C0 toluene, methanol, reflux, 48h. 2 K ,  1 A  19•3  Cross-coupling between phenylboronic acid 104 and aryl halides 113 and 115 afforded oligophenylene products 114 and 115 in high yield. The poor reaction conversion observed in the coupling of 2-methylphenylboronic acid 115 and 1-bro mo-2-methylnaphthalene 116 may be rationalized by the steric crowding involving the methyl substituents in the product 2-methyl-io-tolylnaphthalene 117. Finally, good conversion was observed in the coupling between 2naphthaleneboronic acid 118 and 4-bromobenzonitri le 119. The results of this particular study are preliminary and efforts to optimize the reaction cond itions as well as to investigate the catalyst performance of poly-lOl in Sonogashira and Heck reactions are on-going.  5.4  CONCLUSION  In this Chapter, a novel approach to heterogen eous organometallic catalysts via electrodeposition of oligothiophene complexes onto highly porous graphite electrodes was reported. The thin films of poiy-iOO are efficient in catal yzing several cross-coupling reactions and in the case of the Suzuki reaction allow for the easy recovery and reuse of the supported Pd polymer over several runs without appreciable loss in activit y. In addition, preliminary studies show that thin films of poly-lOl are efficient in catal yzing the Suzuki cross-coupling of a variety of aryihalides and arylboronic acids.  144  5.5  1.  REFERENCES  Tsuji, J., Palladium Reagents and Catalys4 New Perspectives for the 21 Century.  Wiley: Chichester, England, 2004. 2.  Suzuki, A., Chem. Commun. 2005, 38, 4759-4763.  3.  Clayden, J.; Greeves, N.; Warren, S.; Wothers, P., Organic Chemi stry. Oxford  University Press: Oxford, England, 2001; 13 11-1343. p 4.  Cai, Y.  5.  Beletskaya, I. P.; Cheprakov, A. V., Chem. Rev. 2000, 100, 3009-3066.  6.  Sonogashira, K., Metal-Catalyzed Cross-Coupling Reactions. WileyVCH: New York,  Q.; Lu, Y.; Liu, Y.; Gao, G. H., Catal. Lett. 2007, 119, 154-158.  1998. 7.  de Meijere, A.; Diederich, F., Metal-Catalyzed Cross-Coupling Reacti ons. Wiley-VCH:  New York, 2004. 8.  Blaser, H. U.; Indolese, A.; Schnyder, A.; Steiner, H.; Studer, M., I Mo!. Catal. A:  Chem. 2001, 173, 3-18. 9.  Sheldon, R. A.; van Bekkum, H., Fine Chemicals through Heterogenous Catalysis.  Wiley-VCH: Weinham, Germany, 2001. 10.  Yin, L.; Liebscher, J., Chem. Rev. 2007, 107, 133-173.  11.  Garrett, C. E.; Prasad, K., Adv. Synth. Catal. 2004, 346, 889-900.  12.  Clot, 0.; Wolf M. 0.; Patrick, B. 0., 1 Am. Chem. Soc. 2000, 122, 1045610457.  13.  Clot, 0.; Wolf M. 0.; Patrick, B. 0., 1 Am. Chem. Soc. 2001, 123, 9963-9 973.  14.  Pozo-Gonzalo, C.; Berridge, R.; Skabara, P. J.; Cerrada, E.; Laguna, M.; Coles, S. 3.;  Hursthouse, M. B., Chem. Commun. 2002, 20, 2408-2409.  145  15.  Mucci, A.; Parenti, F.; Pigani, L.; Seeber, R.; Zanardi, C.; Pilo, M. I.; Spano, N.;  Manassero, M., J Mater. Chem. 2003, 13, 1287-1292. 16.  Papillon, 3.; Schulz, E.; Gelinas, S.; Lessard, 3.; Lemaire, M., Synth. Met. 1998, 96, 155-  160. 17.  Llobet, A.; Masilorens, E.; Rodriguez, M.; Roglans, A.; Benet-Buchholz, J., Eur. .J  Inorg. Chem. 2004, 1601-1610. 18.  Albano, V. G.; Bandini, M.; Melucci, M.; Monari, M.; Piccinelli, F.; Tommasi, S.;  Umani-Ronchi, A., Adv. Synth. Catal. 2005, 347, 1507-15 12. 19.  Bandini, M.; Melucci, M.; Piccinelli, F.; Sinisi, R.; Tommasi, S.; Umani -Ronchi, A.,  Chem. Commun. 2007, 43, 45 19-4521. 20.  Muilenberg, 0. E., Handbook of X-ray Photoelectron Spectroscopy. Perkin-Elmer  Corporation: New York, 1979. 21.  DiCesare, N.; Belletete, M.; Marrano, C.; Leclerc, M.; Durocher, G., I Phys. Qiem. A  1999, 103, 795-802.  146  CHAPTER 6 Conclusions and Future Directions 6.1  GENERAL CONCLUSIONS  This thesis describes (1) the synthesis and characterization of a series of novel luminescent bent anthradithiophenes, and their solid-state packing structures as single crystals and vacuum deposited films, (2) the third-order nonlinear optical properties of Schiff base-containing conductive polymers prepared by electropolymerization under terrestr ial and microgravity conditions, and (3) the electropolymerization of Pd-containing oligoth iophene complexes that produce heterogeneous polymeric catalysts for C-C cross-couplin g reactions. This section summarizes the results of these studies with general conclusions based on the data presented in this thesis. The development of new materials with enhanced optical and electronic properties is essential for the advancement of organic-based device technology. While device engineering has been monumental in the steady improvement of device performance, a compl imentary approach has been to develop simple synthetic routes to derivatized organic semico nductors as this avenue broadens the capability to purif’ and process materials while offerin g the distinct advantage of chemical modification that could be useful for the optimization of packin g order in the solid state and for structure/property tunability. In Chapter 2, a series of anthrad ithiophenes that are isomers of the organic semiconductors prepared by Katz and co-workers were synthesized via the oxidative photocyclization of a set of readily attainable divinyl precur sors. This strategy afforded a single isomer of the parent and various dialkyl- and diphen yl-derivatives that are 147  soluble in common organic solvents enabling their facile purification. The solid-state packing motifs of these compounds were found to be largely influenced by the substituents tethered to the thiophene groups that induce either cofacial or herringbone packin g arrangements. Moreover, thin films prepared by thermally evaporating these oligoacenes onto silica substrates were found to be highly crystalline with many exhibiting a preferred specific orientation relative to the substrate surface. Although a trend relating the length of the alkyl substituents to the solid-state packing motifs was not observed, the results of these studies are significant as they form a basis for future directions that may lead to the incorporation of these compounds into electronic devices and further studies that may ultimately give rise to a relationship between packing order in the solid state and charge carrier mobility. The effect of gravity on chemical and biological systems is a field of interes t that continues to intrigue scientists and engineers from various disciplines. Studies on combustion, flame ignition, and propagation in microgravity are offering new insights into their mechanisms that may lead to improvements in both the utilization of solid fuels in industry and the safe handling of materials that are used in space-based applications such as insulators for space shuttles and space station 13 s. Crystallization studies carried out in space have shown that microg ravity has a positive effect on the crystal quality of biological macromolecules which has been pivotal for structure elucidation studies on these compo 4 unds. Similar observations have also been observed from crystallization experiments carried out on self-assembling layered tin(IV)sulfides where crystals grown in microgravity were shown to possess smoother faces, greater crystallinity, enhanced optical quality, and larger pore volumes compared to those grown under terrestrial ’ 5 conditi ons.  6  In Chapter 4, the synthesis and characterization of a series of novel  thiophene-functionalized Schiff base complexes with peripheral linear and cyclic alkoxy 148  substituents was described and their electropolymerization under terrestr ial and microgravity conditions investigated. THG measurements were used to probe the micros copic order of the polymer films and this was found to improve when the metallated monomers were electrochemically polymerized in microgravity where buoyancy-driven convec tion currents are largely suppressed. Moreover, the enhancements in third-order susceptibility obtained from polymer films grown in microgravity varied between Cu 2 polymers that differed only in the length of the peripheral alkoxy substituents indicating that in addition to the metal centres, the length of the alkoxy substituent also influences the microscopic order of the polymer films. Although there may be other controlling factors in our experiments that may influence the results of our study, there is evidence that the observed differences betwee n the third-order NLO properties of films grown under microgravity and terrestrial conditions likely originate from the absence of gravity driven convection currents. Immobilizing catalysts onto solid inert supports is a “green” alternative to homogeneous catalytic systems as it offers the facile removal of the active species from the reaction solution that may otherwise be a tedious and expensive process requiring additional separa tion steps and larger volumes of hazardous materials. In Chapter 5, three Pd-containing oligothiophene complexes were electrochemically polymerized onto carbon fibre electro des as potential heterogeneous catalysts for C-C cross-coupling reactions. Although the monomers have the same catalytically active Pd-coordination site, the differences in their connectivities to the oligothiophene unit(s) significantly affected their redox properties, electro polymerization, and subsequent polymer film quality. The Type IT-like polymer modified electro des were found to be efficient in catalyzing Suzuki, Sonogashira, and both intra- and intemo lecular Heck C-C cross-coupling reactions. Moreover, this polymer was found to be reusab le as it catalysed five 149  consecutive Suzuki reactions with high conversions. Through a combi nation of XPS and control experiments, negligible Pd-leaching and overall loss of polymer from the support was observed supporting the conclusion that the catalysis was heterogeneous. In conclusion, the work presented in this thesis has contributed to a better understanding of how alkyl substituents influence the solid-state packing structu re of thiophene-containing oligoacenes in the crystalline phase. These studies will contribute to the overall understanding of how charge carrier mobility is influenced by packing order and to the design and development of novel organic semiconductors with improved device performances in field effect transistors. In addition, the work presented in this thesis suggests that as is the case in crystallization processes, gravity-induced convection currents also influence the process of electropolymerization  affording  electrodeposited  films  of lower  microscopic  order.  Understanding the effects of gravity on chemical systems is essenti al to the design and development of new electrodeposited materials with enhanced electro nic and optoelectronic properties.  6.2  SUGGESTIONS FOR FUTURE WORK  There are several research directions that may be explored stemming from the work presented in this thesis. By incorporating the bent anthradithiophenes (see Chapte rs 2 and 3) into singlecrystal and thin-film field effect transistors, the charge carrier mobili ties of the materials can be measured and correlated with their packing structures in the solid-state. Furthermore, applying the same synthetic strategy that afforded the BADTs but using 3,6-dibromo-o-xylene 121 (Scheme 6-1) instead should give rise to a novel family of heteroacenes based on 125 that are structurally analogues to dibenz[a,i]phenanthrene (i.e., picene). As is the case with BADTs, the 150  solid-state packing order of these materials are expected to change with respect to the length of the ailcyl substituents and comparisons between the two heteroacene families are worth investigating.  Scheme 6-1  \ / —  1) 3 CH C OOH, 2 CO) 3 (CH 0 , S0 Cr0 2 H , 4 3  0\.,/0 Br_—(J_--Br  S0 O 2 H , 2) 4 2 C 3 CH H, H2 H 0  121  122  123  PPh 3 CH B r, 12, UV  123 R_C>R  124  125  In order to establish if the absence of gravity is the main controlling factor responsible for the THG enhancements in the films electrodeposited in microgravity, additional control experiments are required. Preliminary experiments have shown that there is no difference in between films grown in 1 g during flight and films grown moments after once microgravity was achieved. These results suggest that the observed  x differences are likely not due to growing  the polymers on the ground as opposed to growing the films while the plane is airborne, though a more thorough investigation is required. A second control experiment would involve electrodepositing the films at 2 g (a condition that is reached when the Falcon 20 aircraft recovers from a parabolic trajectory). If the hypothesis is correct, films grown under these conditions should give rise to films with lower  values compared to those grown in 0 g and 1  g as a result of the greater g-force.  151  In connection to the relationship observed between  ,  the length of the peripheral alkoxy  chains on the polymer backbone, and the conditions of polymerization (i.e., 0 g vs 1 g), it may be worth extending this investigation to include monomers 130 (Scheme 6-2) and 136 (Scheme 6-3) that include additional alkoxy substituents tethered to the salicylidene moiety of the Schiff base complex. A regioselective Williamson reaction 7 using 2,3-dthydroxybenzaldehyde 126 and an alkyliodide should afford 127 that can be brominated in the 5-position affording compound 128.8 The substituted salicylaldehyde 129 could be prepared via a Stille cross-coupling reaction between 128 and 2-tributylstannylthiophene. 9 Finally, the monomers based on 130 would be prepared via a metal-templated Schiff base condensation between 129 and the appropriate metal salt and phenylenediamine.  152  Scheme 6-2 0  0  0  RI  NBS H  (OH  Br  OR  OH  OR  128  127  126  RO  OR  /\ +  y_SnBu3  ,_,(=0  1/  128  —  2 M(acac)  2 NH  OH  —  4 ) 3 Pd(PPh  N 2 H  OR  129  R  =  ,, 3 CH 13 , H 5 C 17 , H 8 C 15 C 2 H 2H 19 C 2 4  130 The synthetic route to the monomers based on 136 is illustrated in Scheme 6-3. A Williamson reaction using resorcinol 131 could afford 132 that can be regioselectively formylated ortho to the hydroxy group using paraformaldehyde with magnesium dichloride —triethylamine as base. ° 1 Regioselective bromination at the 4-position” followed by a Stille cross-coupling reaction with 2-tributylstannylthiophene will afford salicylaldehyde 136. As in the case of 130, monomers 136 would be prepared via a metal-templated Schiff base condensation between 135 and the appropriate metal salt and phenylenediamine. It is anticipated that polymerizing monomers based on 130 and 136 in microgravity may give rise to electrodeposited films that exhibit even  153  larger third-order susceptibilities compared to their analogues presented in Chapter 4 due to the additional alkoxy substituents that may induce further improvements in microscopic order. Scheme 6-3 (1) MgCI , TEA 2 (2) HCI, H 0 2  (1) NaH, n-Bu Br, 4 (2)RBr  RO  HO  RO  133  132  131  —o  , 0 °C, 2h 2 Br  (y_SnBu3  7=0  133 Br_(OH RO  4 ) 3 Pd(PPh  RO  134 RO  N 2 H  135  135  OR  +  RO  OR  2 NH  2 M(acac)  RO R  =  , , 3 CH 13 , H 6 C 17 , H 8 C 15 C 2 H 2 H 19 C 2 4  OR  136  154  6.3  1.  REFERENCES  Bar-han, A.; Rich, D.; Rein, G.; Fernandez-Peilo, C.; Hanai, H.; Niioka, T. In Flow-  Assisted Flame Propagation Through a Porous Combustible in Microgravity, Western States Section Spring Meeting, San Diego (USA), March 2002; eScholarship Repository, University of California: San Diego (USA), March 2002. 2.  Ronney, P. D. In Understanding Combustion Processes Through Microgravity  Research, Twenty-Seventh International Symposium on Combustion, Combustion Institute, Pittsburgh, 1998, pp 2485-2506. 3.  Goroshin, S.; Kolbe, M.; Bellerose, J.; Lee, J., NASA/CP 2003, 212376/REV1, 341-344.  4.  Vergara, A.; Lorber, B.; Zagari, A.; Giege, R., Acta Ciyst. 2003, D59, 2-15.  5.  Dag, 0.; Ahari, H.; Coombs, N.; Jiang, T.; Aroca-Ouellette, P. P.; Petrov, S.; Sokolov,  I.; Verma, A.; Vovk, G.; Young, D.; Ozin, G. A.; Reber, C.; Pelletier, Y.; Bedard, R. L., Adv.  Mater. 1997, 9, 1133-1149. 6.  Ahari, H.; Bedard, R. L.; Bowes, C. L.; Coombs, N.; Dag, 0.; Jiang, T.; Ozin, G. A.;  Petrov, S.; Sokolov, I.; Verma, A.; Vovk, G.; Young, D., Nature 1997, 388, 857-860.  7.  Kessar, S. V.; Gupta, Y. P.; Mohammad, T.; Goyal, M.; Sawal, K. K., J C’hem. Soc.,  Chem. Commun. 1983, 7, 400-401. 8.  Das, B.; Venkateswarlu, K.; Majhi, A.; Siddaiah, V.; Reddy, K. R., I Mo!. Catal. A:  Chem. 2007, 267, 30-33. 9.  Kingsborough, R. P.; Swager, T. M., Adv. Mater. 1998, 10, 1100-1104.  10.  Hofslokken, N. U.; Skattebol, L., Acta Chern. Scand. 1999, 52, 25 8-262.  155  11.  Meng, C.  Q.;  Ni, L.; Worsencrofi, K. J.; Ye, Z.; Weingarten, M. D.; Simpson, J. E.;  Skudlarek, J. W.; Marino, B. 1VI.; Suen, K.-L.; Kunsch, C.; Souder, A.; Howard, R. B.; Sundell, C. L,; Wasserman, M. A.; Sikorski, 3. A., J Med. C’hem. 2007, 50, 1304-1315.  156  APPENDIX I Crystal Structure Data Table Al-i. Selected Crystal Structure Data for 57, 67, and 68. 57  67  68  5 C 1 H 2 8 0  5 2 C 1 H 2 0 4  Formula  2 1 C o 1 H OS 6  mol wt  298.36  290.38  318.43  TIK  298 (1)  173 (1)  173 (1)  Crystal System  monoclinic  monoclinic  monoclinic  Space Group  P2 / 1 c  P2 / 1 n  P2 / 1 n  a/A  10.5333(6)  12.335(1)  8.5007(15)  b/A  7.6205(4)  4.0116(3)  5.7259(9)  c/A  17.259(1)  13.638(1)  15.333(2)  90.0  90.0  109.384(3)  15.333(2)  90.0  90.0  636.60(9)  741.7(2)  1.515  1.426  2  2  4.01  3.51  6553/1125  7978/1784  (0.025)  (0.037)  90.0  I/o  102.722(2)  /0  90.0  3 v,’A  1351.4(2)  3 pcaiIg cm  1.466  z  4  j..  3.90  (Mo-Ka) /mm 1  Reflection Collected!  14707/3237  Unique (R) Ria; wR ’ [I>2a(f)] t 2  (0.031)  0.044; 0.13 1  0.036; 0.097  0.040; 0.090  Ria; 2 wR (all data) b  0.058; 0.142  0.041; 0.101  0.060; 0.100  aR  = I 0 IF I IF I I -  /  0 I. IF  bwR  ]}’. 2 ) 0 -F [w(F 0 [w(F / ] ={2  157  Table A1-2. Selected Crystal Structure Data for 69, 70, and 71. 69  70  71  S C 3 H 2 0 4  S 4 C 5 H 2 2 8  30 8 C 1 H 2 S  mol wt  458.69  627.00  442.56  TIK  173 (1)  173 (1)  150 (1)  monoclinic  triclinic  monodilnic  P2 1 1 c  P-i  F2 1 1 c  a/A  7.9141(9)  5.3230(8)  20.83 6(3)  b/A  7.0287(9)  6.751(1)  7.2033(10)  c/A  22.219(3)  25.114(4)  6.9755(10)  90.0  90.265(8)  90.0  91.264(8)  93.180(8)  92.019(2)  90.0  97.862(8)  90.0  1235.6(3)  892.6(2)  1046.3(3)  1.233  1.116  1.405  2  1  2  2.31  1.77  3.38  12846/2963  13 115/3115  13486/2619  Formula  Crystal System Space Group  0 p’ 3 v/A pcailg  3 cm  z (Mo-Ku) /mm’ Reflection Collected/ Unique (R) Ria; wR ’ [I>2a(1)] 1 2  (0.029)  (0.084)  (0.058)  0.037; 0.091  0.079; 0.187  0.044; 0.110  Ria; wR b (all data) 2  0.046; 0.096  0.154; 0.232  0069; 0.126  aR  =  0 I IF I I / I IF -  0 I. bwR IF  ]}” ) 0 [w(F . -F 2 0 [w(F / j {2  158  Table A1-3. Selected Crystal Structure Data for 74, 90, and 91. 74  90 (NiC ) 12  91 (CuC ) 12  38 C 1 H 2 S 0  N 5 C 7 H N S 6 O 2 6 8 i  N 5 C 7 H C S 5 O 2 3 0 u  mol wt  442.56  998.03  942.77  TIK  173 (1)  173 (1)  173 (1)  monoclinic  triclinic  monoclinic  P2 /n 1  P -1  P2 /c 1  a/A  9.1796(4)  12.244(1)  24.632(3)  b/A  12.5028(5)  12.373(1)  21.587(2)  c/A  18.3890(8)  18.990(2)  9.652(1)  a!°  90.0  78.3 82(4)  90.0  97.188(2)  81.874(4)  98.85(1)  90.0  73.948(5)  90.0  2093.93(15)  2696.8(5)  5071.0(1)  1.404  1.229  1.235  4  2  4  2.71  4.87  5.60  22474/5003  56427/6407  102340/8987  Formula  Crystal System Space Group  3 viA 3 pca/g cm Z ji.  (Mo-Ku) /mm 1  Reflection Collected! Unique (Rj) Ria; wR ” [I>2a(I)] 2  (0.042)  (0.070)  (0.074)  0.061; 0.105  0.098; 0.158  0.040; 0.095  b (all data) 2 Ria; wR  0.040; 0.094  0.054; 0.129  0.068; 0.110  aR  =  0 I IF I I I IF -  /  0 I. bwR IF  =  ]}’ ) 0 [w(F . -F 2 0 [w(F / ] {2  159  i4  cis ci I  cio  C)  Si  Ci _•_•••___  C12  C2  C)  C17 Cli  C20 Cis  0  •C3  C19  C22  C23  fl  C4 C21  cia  0  C28  C9  Co  C27  52  Li  Figure Al- 1. Oak Ridge Thermal Ellipsoid Plot (ORTEP) of 74 S 15 H 30 (C ) 2 . Thermal ellipsoids are drawn at 50 % probability.  160  Table A 1-4. Fractional atomic coordinates  parameters  ( x 1 O) and equivalent isotropic displacement  2 x 1 O) for 74•* (A x  C(1) C(2) C(3) C(4) C(5) C(6) C(7) C(8) C(9) C(10) C(11) C(12) C(13) C(14) C(15) C(16) C(17) C(18) C(19) C(20) C(21) C(22) C(23) C(24) C(25) C(26) C(27) C(28) C(29) C(30) S(1) S(2)  9570(2) 10737(2) 11079(2) 12146(2) 12062(2) 11032(2) 10836(2) 9721(2) 8879(2) 7753(2) 7024(2) 7473(2) 6890(2) 7494(2) 8730(2) 9284(2) 8626(2) 9199(2) 10130(2) 10121(2) 13272(2) 14031(2) 15083(2) 15397(2) 14681(2) 13628(2) 9489(2) 8252(2) 8557(2) 9991(2) 8835(1) 11011(1)  y  3985(2) 4475(1) 4104(1) 4522(1) 4198(1) 3426(1) 3282(1) 2670(1) 2013(1) 1318(1) 641(1) 502(1) —332(2) —582(2) —27(2) 815(1) 1147(1) 2017(1) 2862(1) 3283(1) 5315(1) 5212(2) 5956(2) 6810(2) 6911(2) 6172(1) 2675(1) 2820(1) 2840(2) 2706(2) 3017(1) 2559(1)  z  U(eq)  11972(1) 11754(1) 11055(1) 10631(1) 9916(1) 9609(1) 8839(1) 8494(1) 8930(1) 8590(1) 8989(1) 9751(1) 10143(1) 10839(1) 11157(1) 10805(1) 10102(1) 9701(1) 10045(1) 10770(1) 10931(1) 11634(1) 11897(1) 11469(1) 10767(1) 10501(1) 7684(1) 7191(1) 6456(1) 6392(1) 11364(1) 7230(1)  27(1) 24(1) 21(1) 21(1) 22(1) 20(1) 21(1) 20(1) 20(1) 25(1) 26(1) 24(1) 30(1) 33(1) 30(1) 25(1) 22(1) 20(1) 19(1) 20(1) 21(1) 29(1) 32(1) 28(1) 27(1) 24(1) 22(1) 24(1) 28(1) 38(1) 26(1) 40(1)  U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.  161  Table A1-5. Bond lengths  (A) of 74.  C(1)—C(2) C(1)—S(1) C(1) —H(1) C(2) —C(3) C(2) —H(2) C(3)—C(20) C(3)—C(4) C(4) —C(5) C(4)—C(21) C(5) —C(6) C(5) —H(5) C(6)—C(19) C(6)—C(7) C(7) —C(8) C(7) —H(7) C(8)—C(9) C(8) —C(27) C(9) —C(18) C(9) —C(10) C(10)—C(11) C(10)—H(10) C(11)—C(12) C(11)—H(11) C(12)—C(13) C(12)—C(17) C(13)—C(14) C(13)—H(13) C(14)—C(15) C(14)—H(14) C(15)—C(16) C(15)—H(15) C(16)—C(17) C(16)—H(16) C(17)—C(18) C(18)—C(19) C(19)—C(20) C(20) —S(1) C(21)—C(26) C(21)—C(22) C(22)—C(23) C(22)—H(22) C(23)—C(24) C(23) —H(23) C(24)—C(25) C(24)—H(24) C(25)—C(26) C(25)—H(25) C(26)—H(26) C(27)—C(28) C(27) —s (2) C(28)—C(29) C(28) —H(28) C(29)—C(30)  1.339 (3) 1.7262 (18) 0.9500 1.438(2) 0.9500 1.409(2) 1.425(2) 1.368(2) 1.487(2) 1.419 (2) 0.9500 1.411(2) 1.416(2) 1.369 (2) 0.9500 1.439 (2) 1.477 (2) 1.412 (2) 1.433(2) 1.351(3) 0.9500 1.422(2) 0.9500 1.411(3) 1.420(2) 1.366(3) 0.9500 1.395(3) 0.9500 1.367(3) 0.9500 1.418 (2) 0.9500 1.450 (2) 1.453 (2) 1.435 (2) 1.7371(17) 1.395(2) 1.396(2) 1.384(3) 0.9500 1.378(3) 0.9500 1.380(2) 0.9500 1.381(2) 0.9500 0.9500 1.374(2) 1.7216(18) 1.414 (3) 0.9500 1.347(3)  162  Table A1-6. Bond lengths  (A) of 74 (continued).  C(29)—H(29) C(30) —s (2) C(30)—H(30)  0.9500 1.7094(19) 0.9500  Table A1-7. Bond angles (deg) of 74. C(2) —C(1) —5(1) C(2) —C(1) —H(1) S(1) —C(1) —H(1) C(1)—C(2)—C(3) C(1)—C(2)—H(2) C(3)—C(2)—H(2) C(20)—C(3)—C(4) C (20) —C(3) —C(2) C(4)—C(3)—C(2) C(5)—C(4)—C(3) C(5)—C(4)—C(21) C(3)—C(4)—C(21) C(4)—C(5)—C(6) C(4) —C(5) —11(5) C(6) —C(5) —H(5) C (19) —C(6) —C(7) C(19) —C(6) —C(5) C(7)—C(6)—C(5) C(8)—C(7)—C(6) C(8)—C(7)--H(7) C(6)—C(7)—H(7) C(7)—C(8)—C(9) C(7) —C(8) —C(27) C(9)—C(8)—C(27) C(18) —C(9)—C(10) C(18) —C(9) —C(8) C(10) -C (9) —C(8) C(11)—C(10)—C(9) C(11) —C(10) —H(10) C(9) —C(10)—H(10) C (10) —C(11) —C(12) C(10) —C(11) —H(11) C(12) —C(11)—H(11) C(13) —C(12) —C(17) C(13) —C(12) —C (11) C(17) —C(12) —C (11) C(14) —C(13) —C (12) C(14) —C (13) —H(13) C(12) —C(13) —H(13) C (13) —C (14) —C(15) C (13) —C(14) —H(14) C(15) —C(14) -H(14) C(16) —C(15) —C(14) C(16) —C(15)—H(15) C(14) —C(15) —H(15)  112 .94 (14) 123 .5 123 .5 113.11(16) 123 .4 123.4 120.27(15) 111.76(15) 127.78(16) 117.21(15) 120.39(16) 122 .34 (15) 122.55(16) 118 .7 118 .7 119.62(15) 121.56(15) 118.66(15) 121.96(16) 119.0 119 .0 118.85(15) 118.07(16) 123.00(15) 119.29 (16) 119.95(15) 120.72(15) 121 .48 (16) 119.3 119.3 120.62 (16) 119 .7 119 .7 119 .74 (16) 120.84(16) 119.13 (16) 120.84(17) 119.6 119 .6 119.50(18) 120 .2 120.2 121.06(17) 119.5 119.5  163  Table A1-8. Bond angles (deg) of 74 (continued). C(16) —C (17)—C(18) C(12) —c (17)—C(18) C(9)—C(18) —C(17) C(9)—C(18)—C(19) C(17) —c (18) —C(19) C(6)—C(19)—C(20) C(6)—C(19)—C(18) C(20) —C(19) —C(18) C(3)—C(20) —C(19) C(3)—C(20)—S(l) C(19)—C(20)—S(1) C(26) —c (21) —C(22) C(26)—C(21)—C(4) C(22)—C(21)—C(4) C(23) —C(22) —C(21) C(23) —C(22) —H(22) C(21) —C(22)—H(22) C(24)—C(23)—C(22) C(24) —c (23) —H(23) C(22) —c (23) —H(23) C(23) —c (24)—C(25) C(23) -c (24) —H(24) C(25) —c (24) —H(24) C(24) —C(25) —C(26) C(24) —C(25) —11(25) C(26) —C(25) —H(25) C(25) —C(26) —C(21) C(25) —C(26)—H(26) C(21) —C(26)—H(26) C(28) —C(27)—C(8) C(28)—C(27)—S(2) C(8)—C(27)—S(2) C(27) —C(28) —C(29) C(27) —c (28) —11(28) C(29) —C(28) —11(28) C(30) —C(29) —C(28) C(30) —C(29) —11(29) C(28) —C(29) —H(29) C(29)—C(30)—S(2) C(29) —C(30)—H(30) S(2)—C(30)—H(30) C(1)—S(1)—C(20) C(30)—S(2) —C(27)  122.90(15) 119.47(15) 117.71(15) 118.50(15) 123 .74 (15) 114.65(15) 118.10(15) 126.83(16) 122.41 (16) 110.37(12) 126.67(13) 118.09 (16) 120.24(15) 121.64(16) 120.48 (17) 119.8 119.8 120.51(16) 119.7 119 .7 119 .75 (17) 120.1 120.1 120.05(17) 120.0 120.0 121.09 (16) 119.5 119.5 132.01(17) 110.11(13) 117.76(12) 112.83(17) 123 .6 123 .6 113.16(16) 123.4 123 .4 111.47(15) 124.3 124.3 91.80(9) 92.43 (9)  164  Table A1-9. Anisotropic displacement parameters (A 2 x 1 O) for 74•*  C (1) C(2) C(3) C(4) C(5) C(6) C(7) C(8) C(9) C(10) C(11) C(12) C(13) C(14) C(15) C(16) C(17) C(18) C(19> C(20) C(21) C(22) C(23) C(24) C(25) C(26) C(27) C(28) C(29) C(30) S(1) S(2)  till  U22  U33  U23  U13  U12  36(1) 29(1) 23(1) 21(1) 21(1) 19(1) 20(1) 21(1) 20(1) 24(1) 23(1) 23(1) 31(1) 43(1) 41(1) 27(1) 23(1) 17(1) 17(1) 19(1) 20(1) 33(1) 33(1) 25(1) 27(1) 23(1) 23(1) 24(1) 31(1) 37(1) 27(1) 24(1)  28(1) 23(1) 20(1) 21(1) 25(1) 22(1) 25(1) 22(1) 22(1) 27(1) 26(1) 22(1) 25(1) 24(1) 25(1) 23(1) 22(1) 22(1) 22(1) 23(1) 23(1) 29(1) 37(1) 29(1) 26(1) 27(1) 25(1) 25(1) 30(1) 63(2) 32(1) 78(1)  18(1) 19(1) 18(1) 21(1) 21(1) 19(1) 18(1) 18(1) 19(1) 22(1) 28(1) 27(1) 33(1) 35(1) 24(1) 23(1) 22(1) 20(1) 18(1) 18(1) 21(1) 24(1) 24(1) 32(1) 29(1) 22(1) 19(1) 23(1) 22(1) 16(1) 20(1) 18(1)  —3(1) —2(1) 1(1) 2(1) 0(1) —1(1) 0(1) —2(1) —2(1) —4(1) —4(1) —2(1) —2(1) 2(1) 2(1) —2(1) —2(1) —1(1) 0(1) 1(1) —2(1) 4(1) 0(1) —5(1) 3(1) 1(1) —2(1) 0(1) 2(1) 2(1) —3(1) 1(1)  7(1) 2(1) 0(1) 2(1) 6(1) 3(1) 7(1) 3(1) 4(1) 3(1) 1(1) 6(1) 8(1) 14(1) 7(1) 4(1) 7(1) 5(1) 3(1) 4(1) 4(1) 0(1) —5(1) 1(1) 6(1) 3(1) 6(1) 4(1) —2(1) 4(1) 9(1) 5(1)  —1(1) —1(1) 1(1) —1(1) —2(1) 0(1) —1(1) 2(1) 1(1) —1(1) —5(1) 0(1) —6(1) —7(1) 3(1) 0(1) 0(1) 0(1) 1(1) 0(1) —1(1) —6(1) —8(1) —8(1) —4(1) 0(1) 0(1) —2(1) —1(1) 5(1) —6(1) 10(1)  2 Ui 1 The anisotropic displacement factor exponent takes the form: -2pi 2 [h 2 a*  +  + 2 hk  a* b* U12  1.  165  Table Al-lO. Fractional hydrogen coordinates (x 1 O) and isotropic displacement parameters  2 x 1O) for 74. (A  x  H(1) H(2) H(5) H(7) H(10) 1-1(11) H(13) H(14) H(15) II(16) H(22) H(23) H(24) H(25) H(26) 1-1(28) 1-1(29) H(30)  9185 11283 12720 11498 7514 6203 6067 7076 9195 10122 13824 15592 16104 14911 13139 7295 7824 10386  y  4152 5013 4503 3619 1334 254 —725 —1130 —237 1184 4626 5878 7327 7489 6249 2899 2939 2694  z  12414 12032 9614 8554 8072 8757 9920 11105 11626 11035 11934 12377 11657 10466 10017 7328 6049 5939  U(eq)  32 28 26 25 29 31 35 40 36 29 35 39 34 32 29 29 34 46  166  Table Al-il. Torsion angles [deg] for 74.  S(1) —C(1) —C(2) —C(3) C(1)—C(2)—C(3) —C(20) C(1)—C(2)—C(3) —C(4) C(20) —C(3)—C(4)—C(5) C(2)—C(3)—C(4) —C(5) C(20)—C(3)—C(4)—C(21) C(2)—C(3)—C(4) —C(21) C(3) —C(4) —C(5) —C(6) C(21) —C (4) —C(5) —C(6) C(4) —C(5) —C(6) —C(19) C(4)—C(5) —C(6) —C(7) C(19) —C(6) —C(7) —C (8) C(5)—C(6) —C(7) —C(8) C(6)—C(7)—C(8) —C(9) C (6)—C (7)—C (8) —C (27) C(7) —C(8) —C(9) —C(18) C(27) —C(8) —C(9) —C (18) C(7) —C(8) —C(9) —C(10) C(27) —C (8) —C (9) —C (10) C(18) —C(9)—C (10) —C(11) C(8) —C(9) —C(10) —C(11) C(9) —C(10)—C (11) —C(12) C(10)—C(11)—C(12)—C(13) C(10)—C(11)—C(12) —C(17) C(17)—C(12)—C(13) —C(14) C(11)—C(12)—C(13) —C(14) C(12)—C(13)--C(14) —C(15) C(13)—C(14)—C(15)—C(16) C(14)—C(15)—C(16) —C(17) C(15)—C(16)—C(17) —C(12) C(15) —C(16)—C(17) —C(18) C(13) —C(12)—C(17) —C(16) C(11) —C(12)—C(17) —C(16) C(13)—C(12)—C(17)—C(18) C(11) —C(12)—C(17) —C(18) C(10) —C(9) —C(18) —C(17) C(8) —C(9) —C(18) —C (17) C(10) —C(9) —C(18) —C(19) C(8)—C(9) —C(18) —C (19) C(16) —C (17) —C(18) —C (9) C(12) —C(17)—C(18) —C (9) C(16)—C(17)—C(18)—C(19) C(12)—C(17) —C(18)—C(19) C(7) —C(6) —C(19) —C (20) C(5) —C(6) —C(19) —C (20) C(7) —C(6) —C(19) —C (18) C(5) —C(6) —C(19) —C(18) C(9) —C(18) —C(19) —C(6) C(17) —C (18) —C(19) —C(6) C(9) —C(18)—C (19) —C(20) C(17) —C(18)—C(19) —C(20) C(4)—C(3) —C(20)—C(19) C(2)—C(3)—C(20)—C(19)  1.8(2) —1.7(2) 173.21(17) 8.6(2) —165.95(16) —174.16(15) 11.3(3) —4.2(2) 178.49(16) —6.7(3) 168.54(16) 5.0(3) —170.32(16) —10.7(3) 172.45(15) 0.8(2) 177.50(16) —176.72(16) 0.0(3) —2.3(3) 175.27(17) —7.7 (3) —169.82(18) 5.0 (3) —5.1(3) 168.67(18) —2.0(3) 4.8(3) —0.5(3) —6.4(3) —178.34(17) 9.0(3) —164.80(17) —178.68(16) 7.5(3) 14.4(2) —163.19(16) —168.26(15) 14.2(2) 154.86 (17) —16.9(2) —22.4(3) 165.83(16) —162.91(15) 12.3 (2) 10.2 (2) —174.56(15) —19.6(2) 157.63(16) 152.64(17) —30.2(3) —2.5(3) 172.87(15)  167  Table A1-12. Torsion angles [deg] for 74 (continued). C(4) —C(3) —C(20) —S(1) C(2)—C(3) —C(20)—S(1) C(6) —C(19) —C(20) —C(3) C(18) —c (19)—C(20) —c (3) C(6)—C(19)—C(20)—S(1) C(18) —c (19) —C(20) —s (1) C(5) —C(4) —C(21) —C(26) C(3) —C(4) —C(21) —C(26) C(5) —C(4) —C(21)—C(22) C(3) —C(4) —C(21)—C(22) C(26)—C(21)—C(22)—C(23) C(4) —C(21) —C(22) —C(23) C(21)—C(22)—C(23)—C(24) C(22)—C(23)—C(24)—C(25) C(23)—C(24)--C(25) —C(26) C(24)—C(25)—C(26) —C(21) C(22)—C(21)—C(26) —C(25) C(4) —C(21) —C(26) —C(25) C(7) —C(8) —C(27) —C(28) C(9) —C(8) —C(27)—C(28) C(7) —C(8) —C(27) —S(2) C(9) —C(8) —C(27) —s (2) C(8)—C(27)—C(28)—C(29) S (2) —C(27) —C(28) —C(29) C(27) —C(28)—C(29)--C(30) C (28) —C(29) —C(30) —S(2) C(2)—C(1)—S(1)—C(20) C(3) —C(20) —5(1) —c (1) C(19) —c (20) —S(1) —C(1) C(29) —C(30) —5(2) —C(27) C(28) —C (27) —5(2) —C(30) C(S) —C(27) —S(2) —C(30)  —174.51(13) 0.82(18) —7.8(2) 179.72(16) 162.87(13) —9.6(3) 38.5(2) —138.69(18) —139.54(18) 43.3(3) 1.4 (3) 179.45(18) —0.1(3) —1.4(3) 1.5(3) —0.2(3) —1.3 (3) —179.37(17) —130.5(2) 52.8(3) 45.0(2) —131.71(15) 175.52(18) —0.3 (2) 0.4(2) —0.3 (2) —1.11(15) 0.12(13) —171.51(16) 0.17(18) 0.06(15) —176.40(15)  168  (:6*  (:5*  Si  CW  C9  (:3*  ci  C7  (:2* (:4* 2 C9*  (:7  (:10*  Cs  81* Co  Figure Al- 2. ORTEP of 68 2 S 1 H 20 (C ) 4 . Thermal ellipsoids are drawn at 50% probability.  Table Al-l3. Fractional atomic coordinates  ( x 1O) and equivalent isotropic displacement  parameters (A 2 x 1O) for 68.*  C(1) C(2) C(3) C(4) C(S) C(6) C(7) C(S) C(9) C(10) S(1)  x  y  z  U(eq)  10308(2) 11287(2) 11346(2) 10384(2) 12205(2) 12053(2) 11045(2) 10182(2) 9171(2) 9959(3) 9426(1)  4781(4) 3848(4) 5166(4) 7120(3) 4675(4) 6077(4) 8068(3) 8637(3) 10545(3) 3910(5) 7323(1)  7168(1) 7833(1) 8628(1) 8538(1) 9458(1) 10154(1) 10086(1) 9256(1) 9192(1) 6247(1) 7488(1)  27(1) 26(1) 23(1) 21(1) 25(1) 24(1) 20(1) 20(1) 21(1) 38(1) 27(1)  U(eq) is defined as one third of the trace of the orthogonalized Uij tensoc.  169  Table A1-14. Bond lengths  (A) of 68.  C(1)—C(2) C(1) —C(10) C(1)—S(1) C(2) —C(3) C(2) —H(2) C(3) —C(4) C(3)—C(5) C(4) —C(S) C(4)—S(1) C(5)—C(6) C(5)—H(5) C(6)—C(7) C(6) —H(6) C(7)—C(9)#1 C(7) —C(8) C(8)—C(9) C(9)—C(7)#1 C(9)—H(9) C(10)—H(1OA) C(10)—H(1OB) C(10)—H(1OC) C(10)—H(1OD) C(10)—H(1OE)  1.351(3) 1.497(3) 1.733(2) 1.430(3) 0.9500 1.384(3) 1.423(3) 1.428(3) 1.7254(18) 1.353(3) 0.9500 1.423(3) 0.9500 1.391(3) 1.433 (2) 1.387(3) 1.391(3) 0.9500 0.9800 0.9800 0.9800 0.9800 0.9800  170  Table A1-15. Bond angles (deg) of 68.  C(2)—C(1)--C(10) C(2)—C(1)—S(1) C(10)—C(1)—S(1) C(1)—C(2) —C(3) C(1)—C(2)-H(2) C(3)—C(2)--H(2) C(4) —C(3) —C(5) C(4)—C(3)—C(2) C(5) —C(3) —C(2) C(3) —C(4) —C(8) C(3)—C(4)—S(1) C(8) —C(4)—S(1) C(6)—C(5)—C(3) C(6)—C(5)—H(5) C(3)—C(5)—H(5) C(5) —C(6) —C(7) C(5) —C(6) —H(6) C(7) —C(6) —H(6) C(9) #1—C(7) —C(6) C(9)#1—C(7)—C(8) C(6) —C(7) —C(8) C(9)—C(8)—C(4) C(9)—C(8)-C(7) C(4)—C(8)—C(7) C(8)—C(9)—C(7)#1 C(8)—C(9)—H(9) C(7)#1—C(9)—H(9) CU) —C(1O) —H(1OA) C(1) —C(10) —H(1OB) H(1OA)—C(10)—H(1OB) C(1) —C(10) —H(1OC) H(1OA) —C(10)—H(1OC) H(1OB) -C(10)--H(1OC) C(1) —C(10) —H(1OD) H(1OA)—C(10)—H(1OD) H(1OB)—C(10)-H(1OD) H(1OC)—C(10) —H(1OD) C(1) —C(10) —H(1OE) H(1OA)—C(10) —H(1OE) H(1OB)—C(10)—H(1OE) H(1OC)—C(10)--H(1OE) H(100)—C(10) -H(1OE) C(1) —C(10) —H(1OF) H(1OA)—C(10)—H(1OF) H(1OB)—C(10)—H(1OF) H(1OC)—C(10)—H(1OF) H(1OD) -C(10)--H(1OF) H(1OE)—C(10)—H(1OF) C(4) —S(1) —CU)  128.4(2) 111.61(15) 120.03(17) 113 .23 (19) 123 .4 123.4 119 .18(18) 112.19 (17) 128.61(19) 122.39 (17) 111.06(14) 126.46(15) 120.25(19) 119.9 119.9 121.80 (18) 119.1 119.1 122.04(17) 118.49(18) 119.43 (17) 123 .46 (17) 119.58(17) 116.92(18) 121.92(17) 119.0 119.0 109.5 109.5 109.5 109.5 109.5 109.5 109.5 141.1 56.3 56.3 109 .5 56.3 141.1 56.3 109.5 109.5 56.3 56.3 141.1 109.5 109.5 91.92 (10)  Symmetry transformations used to generate equivalent atoms: #1 —x÷2,—y+2,—z+2  171  Table A1-16. Anisotropic displacement parameters  C (1) C(2) C(3) C(4) C(5) C(6) C(7) C(8) C(9) C(10) S(1)  Ull  U22  U33  26(1) 24(1) 23(1) 20(1) 24(1) 23(1) 19(1) 20(1) 19(1) 39(1) 28(1)  31 (1) 27(1) 24(1) 25(1) 23(1) 27(1) 23(1) 23(1) 27(1) 47(1) 32(1)  25(1) 28(1) 22(1) 17(1) 27(1) 20(1) 18(1) 17(1) 16(1) 27(1) 18(1)  2 x 1 O) for 68.* (A  U23  —7(1) —4(1) 1(1) —1(1) 3(1) 4(1) 3(1) 0(1) 2(1) —15(1) —4(1)  U13  U12  3(1) 3(1) 1(1) —1(1) —1(1) —3(1) —1(1) —1(1) —3(1) —3(1) —5(1)  —2(1) —1(1) —3(1) —4(1) 1(1) —2(1) —4(1) —5(1) —3(1) 8(1) 3(1)  Table A1-17. Fractional hydrogen coordinates (x 1 O) and isotropic displacement parameters  2 x 1O) for 68. (A  x  H(2) H(5) 1-1(6) H(9) H(1OA) H(1OB) H(1OC) H(1OD) H(1OE) H(1OF)  11876 12888 12635 8610 9202 9507 10941 10565 10260 8826  y  2456 3359 5721 10917 4960 2337 3863 2479 5103 3577  z  U(eq)  7777 9524 10704 8638 5916 6253 5967 6175 5838 6124  2 U) I + The anisotropic displacement factor exponent takes the form: -2pi 2 [h 2 a*  31 30 29 25 57 57 57 57 57 57  ...  + 2 h k a* b* U12  1.  172  Table A1-18. Torsion angles [deg] for 68. C(10) —C (1)—C (2)—C (3) S(1)—C(1)—C(2) —C(3) C(1)—C(2) —C(3)--C(4) C(1)—C(2)—C(3)—C(5) C(5)—C(3) —C(4)—C(8) C(2)—C(3) —C(4)—C(8) C(S) —C(3) —C(4) —5(1) C (2) —C(3) —C(4) —S(1) C(4)—C(3)—C(5)—C(6) C(2) —C(3)—C(5) —C(6) C(3) —C(5) —C(6) —C(7) C(5)—C(6) —C(7)—C(9)#1 C(5) —C(6) —C(7) —C(8) C(3)—C(4)—C(8) —C(9) S(1)—C(4) —C(8) —C(9) C(3) —C(4) —C(S) —C(7) S(1) —C(4) —C(8) —C(7) C(9)#1—C(7) —C(8) —C(9) C(6) —C(7) —C(8) —C(9) C(9) #1—C (7) —C(8)—C(4) C(6) —C(7) —C(8) —C(4) C(4) —C(8) —C(9) —C(7) #1 C(7) —C(8) —C(9) —C(7) #1 C(3)—C(4)—S(1)—C(1) C (8) —C(4) —S(1) —C(1) C(2)—C(1)—S(1) —C(4) C (10) —C (1)—S (1)—C(4)  179.3(2) 0.3 (2) —0.1(3) 178.1(2) —1.8 (3) 176.55(18) —178.49(15) —0.1(2) 1.4 (3) —176.6(2) —0.1(3) 177.07(19) —1.0(3) —177.07(19) —0.9 (3) 0.8(3) 176.92(14) 0.4(3) 178.55(18) —177.49(17) 0.6(3) 177.34(18) —0.4(3) 0.25(16) —176.27(19) —0.31(17) —179.42 (19)  Symmetry transformations used to generate equivalent atoms: #1 —x+2,-y÷2,—z+2  173  Figure Al-. 3. ORTEP of 69 S 34 H 30 (C ) 2 . Thermal ellipsoids are drawn at 50 % probability.  Table Al-19. Fractional atomic coordinates  parameters  *  2x (A  10) for 69.* x  ( x 1 0) and equivalent isotropic displacement y  z  U(eq)  C(1) C(2) C(3) C(4) C(5) C(6) C(7) C(8) C(9) C(10) C(11) C(12)  6806(2) 7096(2) 6643(2) 6000(2) 6819(2) 6361(2) 5669(2) 5483(2) 4825(2) 7152(2) 7833(2) 8353(2)  10330(2) 12042(2) 12130(2) 10425(2) 13675(2) 13478(2) 11736(2) 10147(2) 8458(2) 9707(2) 7702(2) 7183(2)  7717(1) 7974(1) 8591(1) 8792(1) 8999(1) 9577(1) 9795(1) 9397(1) 9612(1) 7088(1) 7044(1) 6412(1)  24(1) 24(1) 22(1) 21(1) 26(1) 26(1) 21(1) 21(1) 22(1) 29(1) 29(1) 29(1)  C(13) C(14)  8864(2) 9484(2)  5114(2) 4604(2)  6357(1) 5739(1)  30(1) 33(1)  C(15) S(1)  9927(3) 5947(1)  2520(3) 8750(1)  5687(1) 8225(1)  51(1) 25(1)  U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.  174  Table A1-20. Bond lengths (A) of 69. C(1) —C(2) C(1) —C(10) C(1)—S(1) C(2)—C(3) C(2)—H(2) C(3)—C(4) C(3)—C(5) C(4)—C(8) C(4) —S(1) C(5) —C(6) C(5) —H(5) C(6)—C(7) C(6)—H(6) C(7) —C(9)#1 C(7) —C(S) C(S) —C(9) C(9)—C(7)#1 C(9)—H(9) C(10)—C(11) C(10)—I-I(1OA) C(10)—H(1OB) C(11)—C(12) C(11)—H(11A) C(11)—H(11B) C(12)—C(13) C(12)—H(12A) C(12)—H(12B) C(13)—C(14) C(13)—H(13A) C(13)—H(13B) C(14)—C(15) C(14)—H(14A) C(14)—H(14B) C(15)—H(15A) C(15)—H(15B) C(15)—H(15C)  1.349(2) 1.4958(19) 1.7342(14) 1.4252(19) 0.9500 1.3805(19) 1.4204(19) 1.4272(18) 1.7227(13) 1.349(2) 0.9500 1.4299(19) 0.9500 1.3904(18) 1.4302(18) 1.3855(18) 1.3904(18) 0.9500 1.513 (2) 0.9900 0.9900 1.5156(19) 0.9900 0.9900 1.515(2) 0 .9900 0 .9900 1.511 (2) 0.9900 0.9900 1.511 (2) 0.9900 0.9900 0.9800 0.9800 0.9800  175  Table A1-21. Bond angles (deg) of 69. C(2) —C(1) —C(10) C(2) —CU) —S(1) C(10) —c (1)—S (1) C(1) —C(2) —C(3) C(1) —C(2) —H(2) C(3)—C(2)—H(2) C(4)—C(3) —C(5) C(4)—C(3)—C(2) C(5)—C(3)—C(2) C(3)—C(4)—C(8) C(3) —C(4) —5(1) C(8)—C(4)—S(1) C(6)—C(5)—C(3) C(6)—C(5)—H(5) C(3)—C(5)—H(5) C(5)—C(6)—C(7) C (5) —c (6) —H (6) C (7) —C (6) —H (6) C(9)#1—C(7)—C(6) C(9)#1—C(7)—C(8) C(6) —C(7) —C(8) C(9)—C(8)—C(4) C(9)—C(8)—C(7) C(4)—C(8)—C(7) C(8)—C(9)—C(7)#1 C(8)—C(9)—H(9) C(7)#1—C(9)—H(9) C(1)—C(10) —C(11) CU) —C(10) —H(1OA) C(11) —C(10)—H(1OA) C(1) —C(10) —H(1OB) C(11) —C(10)—H(1OB) H(1OA) —C(10)—H(1OB) C(10) —C (11) —C(12) C(1O) —C(11)—H(11A) C(12) —C(11)—H(11A) C(10)—C(11)—H(11B) C(12) —C(11)—H(11B) H(11A)—C(11)—H(11B) C(13) —C(12)—C(11) C(13)—C(12)—H(12A) C(11)—C(12)—H(12A) C(13)—C(12)—H(12B) C(11)—C(12)—H(12B) H(12A)—C(12)—H(12B) C(14) —C (13) —C(12) C(14)—C(13) —H(13A) C(12)—C(13)—H(13A) C(14)—C(13) —H(13B) C(12)—C(13)—H(13B) H(13A)—C(13)—H(13B) C(15) —C (14) —C(13) C(15)—C(14)—H(14A)  128.60(13) 111.16(10) 120.23 (11) 113.68(12) 123 .2 123.2 119 .25 (12) 112.06 (12) 128.65(13) 122.61(12) 111.13 (10) 126.26(10) 120.37(13) 119.8 119 .8 121.50(13) 119 .3 119 .3 121 .49 (12) 118.85(12) 119.66(12) 124.05(12) 119.35(12) 116.60(12) 121.81(12) 119 .1 119 .1 113.97(12) 108.8 108.8 108.8 108.8 107.7 112.84(12) 109.0 109.0 109.0 109.0 107.8 112.58(13) 109.1 109.1 109.1 109.1 107.8 113.21(13) 108.9 108.9 108.9 108.9 107.7 112.31(15) 109.1  176  Table A1-22. Bond angles (deg) of 69 (continued).  109.1 109.1 109.1 107.9 109.5 109.5 109.5 109.5 109.5 109.5 91.97(7)  C(13)—C(14)—H(14A) C(15)—C(14)—H(14B) C(13)—C(14)—H(14B) H(14A)—C(14)-H(14B) C(14)—C(15)—H(15A) C(14)—C(15)—H(15B) H(15A)—C(15)—H(15B) C(14)—C(15)—H(15C) H(15A)—C(15)—H(15C) H(15B)—C(15)—H(15C) C(4)—S(1)—C(1)  Symmetry transformations used. to generate equivalent atoms: #1 —x+1,—y÷2,-z+2  Table A1-23. Anisotropic displacement parameters Ull  U22  U33  26(1) 26(1) 22(1) 22(1) 29(1) 32(1) 22(1) 21(1) 26(1) 37(1) 32(1) 30(1) 30(1) 29(1)  26(1) 24(1) 21(1) 20(1) 19(1) 18(1) 19(1) 20(1) 19(1) 29(1) 30(1) 31(1) 32(1) 38(1)  21(1) 23(1) 23(1) 20(1) 29(1) 26(1) 23(1) 21(1) 21(1) 21(1) 24(1) 25(1) 28(1) 34(1)  C(15)  55(1)  47(1)  5(1)  34(1)  21(1)  C(1) C(2) C(3) C(4) C(5) C(6) C(7) C(8) C(9) C(10) C(11) C(12) C(13) C(14)  *  2 x 1 O) for 69.* (A U23  U13  U12  2(1) 3(1) 1(1) —1(1) 1(1) —3(1) —1(1) —1(1) —3(1) 0(1) —2(1) —3(1) —4(1) —10(1)  3(1) 3(1) 1(1) 1(1) 2(1) 0(1) 0(1) —1(1) 0(1) 5(1) 4(1) 6(1) 2(1) 3(1)  2(1) —1(1) 0(1) 1(1) —3(1) —3(1) 1(1) 2(1) 0(1) 2(1) 3(1) 0(1) 3(1) 3(1)  52(1)  —16(1)  —4(1)  20(1)  —2(1)  4(1)  The anisotropic displacement factor exponent takes the form: -2pi 2 [h 2 a*Z Ui 1 +  ...  +  19(1) —2(1)  2 h k a* b* U12].  177  Table A 1-24. Fractional hydrogen coordinates (x 1 O) and isotropic displacement parameters  2 x 1O) for 69. (A x  H(2) H(5) H(6) H(9) H(10A) H(1OB) H(11A) H(11B) H(12A) H(12B) H(13A) H(13B) H(14A) H(14B) H(15A) H(15B) H(15C)  7558 7263 6502 4708 7977 6092 6956 8823 7399 9312 9768 7881 8597 10495 10798 10355 8916  y  13090 14853 14521 7404 10593 9795 6797 7569 7444 7999 4836 4302 4920 5378 2197 2263 1749  z  7764 8865 9846 9347 6911 6845 7176 7321 6128 6296 6659 6449 5434 5652 5991 5285 5753  U(eq)  29 31 31 26 35 35 35 35 34 34 36 36 40 40 77 77 77  178  Table A1-25. Torsion angles [deg] for 69.  C(10) —C(1) —C(2) —c (3) S(1) —C(1) —C(2) —C(3) C(1)—C(2) —C(3) —C(4) CU) —C(2) —C(3)—C(5) C(5) —C(3) —C(4) —C(8) C(2) —C(3)—C(4)—C(8) C(5) —C(3) —C(4) —S(1) C(2) —C(3) —C(4) —S(1) C(4) —C(3) —C(S) —C(6) C(2) —C(3) —C(5) —C(6) C(3)—C(5)—C(6)—C(7) C(5)—C(6)—C(7) —C(9)#1 C (5) —C(6) —C(7) —C(8) C (3) —C (4) —C (8) —C (9) S(1) —C(4) —C(8) —C(9) C(3) —C(4) —C(8)—C(7) S(1) —C(4) —C(8) —C(7) C(9) #1—C(7) —C(8) —C(9) C(6) —C(7) —C(8) —C(9) C(9)#1—C(7) —C(8) —C(4) C(6)—C(7)—C(8) —C(4) C(4) —C(8) —C(9) —C(7) #1 C(7) —C(8) —C(9) —C(7) #1 C (2) —C(1) —C(10) —C (11) S (1) —CU) —C(10) —C(11) C(1) —C(10)—C(11)—C(12) C(1O)—C(11)—C(12)—C(13) C(11)—C(12)—C(13) —C(14) C(12)—C(13)—C(14)—C(15) C(3) —C(4) —S(1) —C(1) C(8) —C(4) —S(1) —CU) C(2) —C(1) —S(1) —C(4) C(10) —C(1) —s (1) —C(4)  —178 .73 (14) 0.36(17) —0.01(18) 178.02(15) 0.7(2) 178.91(13) —178.59(11) —0.36(15) —0.1(2) —178 .02 (15) —0.8(2) —179.09(14) 1.2 (2) 179.65(13) —1.2 (2) —0.3(2) 178.85(11) —0.3(2) 179.45(12) 179.66(13) —0.60(19) —179.64(13) 0.3 (2) 140.04(16) —38.99(18) —173.68(13) —174.11(13) —176.56(13) —177.95(14) 0.48(11) —178.76(13) —0.48(12) 178.70(12)  Symmetry transformations used to generate equivalent atoms: #1 —x+1,—y+2,—z÷2  179  :*  Si CiS  Ci4  Figure Al- 4. ORTEP of 71 2 S 1 H 30 (C ) 8 . Thermal ellipsoids are drawn at 50 % probability.  Table Al-26. Fractional atomic coordinates parameters  2x (A  1 0) for 71  C(7)  C(8) C(9)  C(10) C(11) C(12) C(13) C(14) C(15) S(1)  x  1 0) and equivalent isotropic displacement  .  x  C(1) C(2) C(3) C(4) C(S) C(6)  (  6358(1) 5675(1) 5356(1) 5308(1) 5634(1) 6284(1) 6665(1) 7346(1) 7552(1) 8211(1) 8691(1) 9311(1) 9477(1) 9008(1) 8381(1) 6911(1)  y  186(3) 191(3) 608(3) —436(3) —905(3) —868(3) —372(3) —468(3) 7(3) 14(3) —1033(3) —1022(3) 26(4) 1044(3) 1042(3) 635(1)  z  4811(3) 4945(3) 6615(3) 3283(3) 1570(3) 1491(3) 3164(3) 3439(3) 5266(3) 6085(3) 5228(3) 5977(3) 7595(3) 8461(3) 7724(3) 6669(1)  U(eq)  28(1) 28(1) 28(1) 28(1) 31(1) 31(1) 29(1) 31(1) 30(1) 31(1) 35(1) 39(1) 39(1) 42(1) 38(1) 31(1)  U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.  180  Table A1-27. Bond lengths (A) of 71. C(1)—C(7) C(1)—C(2) C(1)—S(1) C(2)—C(3) C(2)—C(4) C(3)—C(4)#1 C(3)—H(3) C(4)—C(3)#1 C(4)—C(5) C(5)—C(6) C(5)—H(5) C(6)—C(7) C(6)—H(6) C(7)—C(8) C(8)—C(9) C(8)—H(8) C(9)—C(10) C(9)—S(1) C(10)—C(15) C(10)—C(11) C(11)—C(12) C(11)—H(11) C(12)—C(13) C(12)—H(12) C(13)—C(14) C(13)—H(13) C(14)—C(15) C(14)—H(14) C(15)—H(15)  1.393(3) 1.429(3) 1.734(2) 1.394(3) 1.439(3) 1.395(3) 0.9500 1.395(3) 1.435(3) 1.358(3) 0.9500 1.433(3) 0.9500 1.427(3) 1.374(3) 0.9500 1.469(3) 1.743(2) 1.397(3) 1.404(3) 1.376(3) 0.9500 1.391(3) 0.9500 1.379(3) 0.9500 1.387(3) 0.9500 0.9500  181  Table A1-28. Bond angles (deg) of 71. C(7)—C(1)—C(2) C(7)—C(1)—S(1) C (2) —C(1) —s (1) C(3)—C(2)—C(1) C(3)—C(2)—C(4) C(1)—C(2)—C(4) C(2)—C(3)—C(4)#1 C(2)—C(3)—H(3) C(4)#1—C(3)—H(3) C(3)#1—C(4) —C(5) C(3)#1—C(4)—C(2) C(S) —C(4) —C(2) C(6) —C(S) —C(4) C(6) —C(5) —H(5) C(4)—C(5) —H(5) C(5)—C(6)—C(7) C(5)—C(6)—H(6) C(7)—C(6) —H(6) C(1)—C(7)—C(8) C(1)—C(7)—C(6) C(8)—C(7)—C(6) C(9)—C(8)—C(7) C(9)—C(8)—H(8) C(7) —C(8) —H(8) C(8)—C(9)--C(10) C(8)—C(9)—S(1) C(10)—C(9)—S(1) C(15) —C(10)—C(11) C(15)—C(10)—C(9) C(11)—C(10)—C(9) C(12) —C(11) —C(10) C(12) —C(11) —H(11) C(10) —C(11) —H(11) C(11) —C(12) —C(13) C(11) —C(12) —H(12) C(13) —C(12) —H(12) C(14) —C(13) —C(12) C(14) —C(13)—H(13) C(12) —C(13) —H(13) C(13) —C(14) —C(15) C(13) —C(14) —H(14) C(15) —C(14) —H(14) C(14) —C(15) —C(10) C(14) —C(15) —H(15) C(10) —C(15) —H(15) C(1) —5(1) —C(9)  122.76 (18) 111.00(16) 125.97(16) 124.07(18) 119.07(18) 116.62 (18) 121.76(18) 119 .1 119.1 121.35 (18) 119.17(18) 119 .48 (18) 122.02 (19) 119.0 119.0 119.78 (19) 120.1 120.1 112.68(18) 119.11(19) 128.11(19) 112.95 (19) 123.5 123.5 128.28 (19) 111.38 (16) 120.33(16) 118.0(2) 121.76(19) 120 .22 (19) 120.6(2) 119.7 119.7 120.9(2) 119 .5 119.5 119.0(2) 120.5 120.5 120.7(2) 119.7 119.7 120.8(2) 119 .6 119 .6 91.95(10)  Symmetry transformations used to generate equivalent atoms: #1 —x+1,—y,—z+1  182  Table A1-29. Anisotropic displacement parameters (A 2 x 1O) for 71.*  C(1) C (2) C(3) C(4) C(S) C(6) C(7) C(8) C(9) C(10) C(11) C(12) C(13) C(14) C(15) S(1)  Ull  U22  U33  U23  U13  U12  33(1) 31(1) 33(1) 34(1) 38(1) 37(1) 33(1) 33(1) 31(1) 30(1) 32(1) 34(1) 32(1) 40(1) 36(1) 30(1)  25(1) 23(1) 26(1) 23(1) 30(1) 30(1) 24(1) 29(1) 27(1) 30(1) 39(1) 44(1) 44(1) 45(1) 41(1) 35(1)  27(1) 28(1) 26(1) 26(1) 25(1) 26(1) 29(1) 31(1) 32(1) 31(1) 34(1) 40(1) 42(1) 39(1) 36(1) 29(1)  0(1) —1(1) —2(1) 1(1) —2(1) —1(1) 1(1) 1(1) —1(1) 1(1) —2(1) 1(1) 3(1) —6(1) —6(1) —4(1)  —2(1) —3(1) —3(1) —2(1) —3(1) 1(1) 1(1) 2(1) 1(1) —1(1) 1(1) 2(1) —4(1) —6(1) —1(1) —1(1)  —1(1) 0(1) —1(1) 2(1) 1(1) 3(1) —1(1) 0(1) —1(1) —2(1) 2(1) 4(1) —1(1) —1(1) 2(1) 0(1)  Table A1-30. Fractional hydrogen coordinates (x 1 O) and isotropic displacement parameters x 10) for 71. 2 (A x  H(3) H(5) H(6) H(8) 11(11) H(12) H(13) H(14) 1-1(15)  *  5598 5387 6485 7627 8587 9630 9907 9115 8063  y  1021 —1252 —1169 —823 —1756 —1740 40 1755 1747  z  U(eq)  7714 457 331 2461 4120 5380 8095 9574 8342  2 Ui 1 The anisotropic displacement factor exponent takes the form: -2pi 2 [h 2 a*  +  34 37 37 37 42 47 47 50 45  +2 hk  a* b* U12  1.  183  Table A1-31. Torsion angles [degj for 71. C(7) —C(1) —C(2) —C(3) S(1) —C(1) —C(2) —C(3) C(7)—C(1)—C(2)—C(4) S(1) —CU) —C(2) —C(4) C(1) —C(2) —C(3) —C(4) #1 C(4) —C(2) —C(3) —C(4) #1 C(3) —C(2) —C(4) —C(3) #1 CU) —C(2) —C(4) —C(3) #1 C(3) —C(2) —C(4) —C(5) CU) —C(2) —C(4) —C(S) C(3)#1—C(4)—C(5) —C(6) C(2) —C(4) —C(S) —C(6) C(4) —C(S) —C(6) —C(7) C(2) —C(1) —C(7) —C(8) S(1) —C(1) —C(7) —C(8) C(2) —C(1) —C(7) —C(6) S(1) —C(1) —C (7) —C(6) C(S) —C(6) —C(7) —C(1) C(5)—C(6) —C(7)—C(8) C(1)—C(7)—C(8)—C(9) C(6)—C(7) —C(8)—C(9) C(7) —C(8) —C(9) —C(10) C(7) —C (8) —C(9) —8(1) C(8) —C(9) —C (10)—C (15) S(1) —C(9) —C (10) —C (15) C(8) —C(9) —C (10) —C (11) S (1) —C(9) —C (10) —C (11) C(15)—C(10)—C(11)—C(12) C(9)—C(10) —C(11)—C(12) C(10) —C(11)—C(12)—C(13) C(11)—C(12)—C(13)—C(14) C(12)—C(13)—C(14)—C(15) C(13) —C(14)—C(15)—C(10) C(11) —C(10)—C(15)—C(14) C(9) —C(10) —C(15) —C(14) C(7) —C(1) —s (1) —C(9) C(2) —C(1) —5(1) —C(9) C(8) —C(9) —s (1) —C(1) C(10) —C(9) —S(1) —C (1)  175.05(19) 1.6(3) 0.7(3) —172.82(15) —174.28(19) 0.0(3) 0.0 (3) 174.71(18) —178.74(18) -4.1(3) —175.34(19) 3.4(3) 0.9(3) —173 .07 (18) 1.3(2) 3.5(3) 177.86(15) —4.3(3) 171.7 (2) 0.1(3) —176.1(2) 178.0 (2) —1.4(2) 160.0(2) —20.7(3) —20.3 (3) 159.02(17) —0.8(3) 179. 5(2) —0.1(4) 0.8(4) —0.6(4) —0.3 (4) 0.9 (3) —179.3(2) —1.74(16) 172.39(19) 1.80(17) —177.63(18)  Symmetry transformations used to generate equivalent atoms: #1 —x+1,-y,-z+1  184  APPENDIX 2 Electronic Absorption Data of Schiff Base Monomers and Polymers Table A2-1. Electronic absorption maxima  (2max)  of Schiff base complexes and their  corresponding polymers. Sample 80 (MFC ) 0  [nm]a 279  ‘max  Sample 0 poly-MFC  [nml 383  max  83 (VOC)  315, 458  0 poly-VOC  n/a b  ) 0 84(NiC  317,383,504  0 poly-N1C  385  85 (CuC ) 0  316, 466  poly-CuCo  399  81 (MFC ) 6  277, 371  6 poly-MFC  385  86 (VOC ) 6  304, 446  poly- VOC 6  n/a b  ) 6 87(NiC  317,388,508  6 poly-NiC  388  88 (CuC ) 6  314, 464  6 poly-CuC  398  82 (MFC ) 12  276, 368  poly- MFC 12  384  89 (V0C ) 12  301, 442  poly- V0C 12  n/a b  ) 12 90(NiC  317,388,507  12 poly-NiC  389  91 (CuC ) 12  319, 380, 425, 462  poly- CuC 12  393  a  C1 b broad absorption, no clear maximum. CH , 2  185  APPENDIX 3 Cyclic Voltammograms of BADTs and Metallated Schiff Base Monomers  C)  0  ci) I. I—  C).  0  0  -t  C)  0.0  0.2  0.4  0.6  0.8  1.0  1.2  1.4  Potential (V) vs SCE  Figure A3-1. Cyclic voltammogram of 68 in DCM containing 0.1 M 6 N]PF Scan rate 4 [(n-Bu) .  =  100 mV/s, 3 cycles.  186  C.) 0 C  C ci)  C)  C.)  0  C-) I  0.2  0.4  •  I  I  0.6  0.8  •  I  1.0  1.2  1.4  Potential (V) vs SCE  Figure A3-2. Cyclic voltammogram of 69 in DCM containing 0.1 M 6 N]PF Scan rate = 4 [(n-Bu) . 100 mV/s.  Potential (V) vs SCE  Figure A3-3. Cyclic voltammogram of 70 in DCM containing 0.1 M . 6 N 4 [(n-Bu) ]PF Scan rate  =  100 mV/s.  187  C)  0 C  C 1  0 C)  0  0.2  0.4  0.6  0.8  1.0  1.2  1.4  1.6  1.8  Potential (V) vs SCE  Figure A3-4. Cyclic voltammogram of 89 (VOC ) in DCM containing 0.1 M 6 12 N]PF 4 [(n-Bu) . Scan rate = 100 mV/s.  0 0 C  C  ci). 1.  D  C.) 0  0  0  0.0  0.2  0.4  0.6  0.8  1.0  1.2  1.4  1.6  1.8  Potential (V) vs SCE  Figure A3-5. Cyclic voltammogram of 90 (NiC ) in DCM containing 0.1 M 6 12 N]PF 4 [(n-Bu) . Scan rate = 100 mV/s 188  /  / ‘7 /,/  oC  ‘\  //  /,// /i/ C 0  1110 -02  0’O  0’2  0’40  0’8  114  1’2  1€  Potential (V) vs SCE  Figure A3-6. Cyclic voltammogram of 94 (CuC ) in DCM containing 0.1 M 6 8 N]PF 4 [(n-Bu) . Scan rate  100 mV/s.  C,  oC  -  -  —-— -  --  -  / -  /  /7  C,  C)  \N  /‘,/  /  -  0.2  0.4  0.6  0.8  1.0  1.2  1.4  1.6  Potential (V) vs. SCE  Figure A3-7. Cyclic voltammogram of 95 (CuC ) in DCM containing 0.1 M 6 14 N]PF 4 [(n-Bu) . Scan rate  =  100 mV/s. 189  C)  /  0 C  ./ /  /  \\  / /  /  F (  --  0.0  0.2  0.4  0.6  0.8  1.0  1.2  1.4  Potential (V) vs SCE  Figure A3-8. Cyclic voltammogram of 96 (CuCMCCY) in DCM containing 0.1 M 6 N]PF 4 [(n-Bu) . Scan rate  =  100 mV/s.  190  APPENDIX 4 NLO Data of Schiff Base Polymers  , poly-VOC6, poly-N1C6, and poly-CuC 6 Table A4-1. NLO data for poly-MFC . 6 ig  Og Sample  6 poly-MFC  6 poly-VOC  6 poly-NiC  6 poly-CuC  (esu)  %-error  (esu)  %-error  1.04642E-1 1  21.91141  1.99737E-1 1  9.93001  1.40536E-11  27.81177  1.07083E-11  18.6339  1.40536E-1 1  27.81177  8.67405E-12  26.35231  0  7.51079E-12  23.57023  0  9.04827E-12  20.75666  2.95834E-1 1  3 1.50544  2.41964E-1 1  17.45592  2.32282E-11  15.67581  2.27414E-11  24.74358  6.49651E-1 1  7.82437  4.31236E-11  28.72882  2.6875E-11  20.58321  3.67188E-11  20.12291  2.34443E-11  22.09709  3.44831E-11  13.06137  191  , poly-VOC 12 Table A4-2. NLO data for poly-MFC , poly-NiCi 12 , and poly-CuC 2 . 12 Og  ig  Sample  x (esu)  %-error  x (esu)  %-error  12 poly-MFC  1.81760E-11  42.52369  3.97434E-11  10.2754  1.49079E-11  20.75985  1.82293E-11  23.33833  1.18470E-11  7.85674  3.57585E-1 1  17.21279  2.1 8982E-1 1  15.48989  3.11240E-11  20.80028  1.73454E-11  18.22172  4.39586E-11  13.76661  4.59559E-1 1  21.20913  3.99185E-1 1  32.89446  8.96127E-11  11.37496  3.00156E-11  20.32789  6.97286E-11  28  2.77836E-11  12.37374  9.20131E-11  15.78641  2.26852E-11  17.42424  1.39510E-10  14.70886  I .87464E-10  17.31192  6.14953E-1 1  26.08573  1.87783E-10  18.64559  2.91699E-11  8.75303  2.27356E-10  14.05233  7.61210E-11  12.12297  2.36049E-10  37.15149  4.29708E-11  21.13752  1.10034E-10  42.10068  12 poly-V0C  12 poly-NiC  12 poly-CuC  192  Table A4-3. NLO data for PO , and poly-CuC 8 . 14 Y-CUCMeCY, poly-CuC 1 Og Sample YCUCMeCy 1 P0  8 poly-CuC  14 poly-CuC  (esu)  ig %-error  (esu)  %-error  7.40370E41  25.42424  6.35078E11  22.49631  7.42305E-11  21.63636  6.63953E-11  21.01248  7.62914E-11  21.25758  6.48418E-11  21.01248  8.OO111E-11  20.61204  5.12145E-11  24.23377  7.70715E-11  22.04140  4.90351E-11  21.25758  6.48982E- 11  20.99716  4.6891 5E-1 1  20.42424  1.3920E-10  23.75758  2.52296E-1 1  22.09091  1.50352E-10  22.97326  2.42958E-11  21.25758  1.55574E-10  22.64646  2.22715E-11  20.93706  1.52572E-10  19.47186  5.61125E-11  21.63636  1.17812E-10  20.66234  4.11801E-11  23.09091  1.22588E-10  20.42424  4.49089E-11  21.96896  3.85218E-11  22.64646  2.06172E-11  33.75758  5.39747E-11  21.8986  1.78404E-11  42.09091  3.65611E-11  24.23377  1.96984E-11  29.59091  1.86757E-10  21.85281  2.46193E-11  27.09091  6.05073E- 11  21.43874  2.6482E- 11  24.23377  1.04564E-10  20.66234  2.68819E-11  24.23377  193  APPENDIX 5 ANOVA Analysis Results poly-CuC and , Table A5-1. ANOVA results from P01YCUCMeCy, poly-CuCs, poly-CuC , 14 12 12 NLO data. poly-N1C Sample  Degrees of Freedom  F-Ratio  p  (1,12)  23.269  0.000  (1,12)  0.216  0.650  (1,12)  197.747  0.000  (1,12)  0.323  0.580  53 x  (1,7)  26.192  0.001  %-error  (1,7)  1.431  0.271  (1,12)  7.189  0.020  (1,12)  12.094  0.005  (1,7)  10.350  0.015  (1,7)  0.052  0.631  PO1YCUCMeCy  %-error  poly-CuCs  %-error 12 poly-CuC  14 poly-CuC  %-error  12 poly-NiC  %-error  194  APPENDIX 6 H NMR Spectra 1 For  NIVIR spectra of compounds 57-60, 62-66, and 67-70, see reference: Pietrangelo, A.;  MacLachlan, M.J.; Wolf M.O.; Patrick, B.O. Org. Lett. 2007, 9, 3571-3573.  Qpm ‘t1)  10.00  9.50  9.00  8.50  &00  7.50  7.00  Figure A6-1. ‘H NMR spectrum of 61. (400 MHz, 2 CI ca. 25 °C) CD ,  195  pm (ti)  7.50  7.00  6.50  6.00  5.50  Figure A6-2. ‘H NMR spectrum of 66. (400 MHz, , CI Ca. 25 °C) 2 CD  $r,9P(f1)  8.50  8.00  7.50  Figure A6-3. ‘H NMR spectrum of 71. (400 MHz, , C1 Ca. 25 °C) 2 CD 196  J 7.50  a,iA9’t1)  I  6.50  7.00  6.00  5.50  Figure A6-4. ‘H NMR spectrum of 72. (400 MI-{z, 2 C1 Ca. 25 °C) CD ,  1 ppm 9j9  i  \I11I,k ‘I  7.50  7.00  Figure A6-5. ‘H NMR spectrum of 73. (400 MHz, , C1 ca. 25 C) 2 CD  197  jI  8.50  ppm (tI)  7.50  8.00  Figure A6-6. ‘H NMR spectrum of 74. (400 MHz, 2 C1 ca. 25 C) CD ,  Qoop  I  I  ppm (fI)  7.0  6.0  I  I  5.0  4.0  3.0  I  I  I  I  2.0  I  I  I  1.0  I  I  0.0  Figure A6-7. 1 H NIVIR spectrum of 96. (400 MHz, 2 CI Ca. 25 C) CD ,  198  OOp  N 2 0  I  I  pp&t1)  8.0  2 NO  I  7.0  6.0  I  5.0  I  I  4.0  I  3.0  I  I  2.0  L I  I  I  1.0  I  I  0.0  Figure A6-8. ‘H NMR spectrum of 97. (400 MHz, 2 CI Ca. 25 °C) CD ,  Qoop  0 CJOH HQD-()  -J ‘  I  125 ppm (t1j  I  10.0  I  7.5  Figure A6-9. ‘H NIvIR spectrum of 98. (400 MHz, 2 C1 CD ,  I  5.0  Ca.  I  I  2.5  25 C)  199  15 C 2 H 0 2  ppm (U)  7.0  25 H 12 0C  6.0  5.0  4.0  3.0  2.0  1.0  Figure A6-10. ‘HNMR spectrum of 90. (400 MHz, , C1 ca. 25 °C) 2 CD  200  

Cite

Citation Scheme:

        

Citations by CSL (citeproc-js)

Usage Statistics

Share

Embed

Customize your widget with the following options, then copy and paste the code below into the HTML of your page to embed this item in your website.
                        
                            <div id="ubcOpenCollectionsWidgetDisplay">
                            <script id="ubcOpenCollectionsWidget"
                            src="{[{embed.src}]}"
                            data-item="{[{embed.item}]}"
                            data-collection="{[{embed.collection}]}"
                            data-metadata="{[{embed.showMetadata}]}"
                            data-width="{[{embed.width}]}"
                            async >
                            </script>
                            </div>
                        
                    
IIIF logo Our image viewer uses the IIIF 2.0 standard. To load this item in other compatible viewers, use this url:
http://iiif.library.ubc.ca/presentation/dsp.24.1-0060813/manifest

Comment

Related Items