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Synthesis of triple-stranded supramolecular complexes using poly(dipyrromethene) ligands Zhang, Zhan 2010

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 SYNTHESIS OF TRIPLE-STRANDED SUPRAMOLECULAR COMPLEXES USING POLY(DIPYRROMETHENE) LIGANDS      by ZHAN ZHANG  B. E., Wuhan University, 1997 M. Sc., Wuhan University, 2000      A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMETS FOR THE DEGREE OF  DOCTOR OF PHILOSOPHY    in  THE FACULTY OF GRADUATE STUDIES  (Chemistry)  THE UNIVERSITY OF BRITISH COUMBIA  (Vancouver)  April 2010  © Zhan Zhang, 2010 ABSTRACT  Composed of conjugated dipyrromethene moieties connected by a linker, poly(dipyrromethene)s are useful ligands for the formation of well-defined architectures through self-assembly. Analogous to porphyrins, poly(dipyrromethene) ligands can endow their metal complexes with intense absorption bands in the visible region. The primary objectives of this project were to synthesize triple-stranded poly(dipyrromethene) complexes and explore the octahedral coordination chemistry of poly(dipyrromethene) ligands. HN NH Ph Ph O O 238 HN NH Ph Ph O O   257201 HN NH H H O ON H α α ββ  A series of α,α’-linked and β,β’-linked bis(dipyrromethene) ligands were synthesized and examined for the formation of triple-stranded complexes. It was found that the size of α-substituent was the key factor. To facilitate the synthesis of the novel α-free bis(dipyrromethene) ligands, a method was developed to prepare the unknown key precursors, β,β’-linked α-unsubstituted diformyldipyrromethanes (201, for example) and diacyldipyrro- methanes (238 and 257, for example). HN NH N NHBr HBr 220-H2. 2HBr HN NH N N Ph Ph 260-H2 HN NH N N Ph Ph 250-H2 201. Due to the presence of four exceedingly reactive α-positions, the proligand is u  Alkyl-substituted α-free bis(dipyrromethene) proligand 220-H2·2HBr was synthesized from the β,β’-linked nstable in solution. In order to improve the stability of the α-free proligand, aryl-substituted  ii bis(dipyrromethene) proligands 250-H2 and 260-H2 were also developed from 238 and 257, respectively. Upon coordination with trivalent metals, these α-free proligands produced uncharged triple-stranded complexes which have intense absorption around 500nm. Intriguingly, the complexation led to both helicate and mesocate. The diastereomers were, for the first time, isolated and found inconvertible to each other under the reaction conditions. The case provids a new scenario for the formation of helicates versus mesocates and indicates the empirical odd-even rule is too simple to predict the product(s) of such a process.  iii TABLE OF CONTENTS ABSTRACT………………………………………….……………………...ii TABLE OF CONTENTS…………..……………….......………………......iv LIST OF TABLES……………………………..………….………………..vii LIST OF FIGURES…………………………………………..………..........ix LIST OF SCHEMES………………………………………….…………...xiv LIST OF ABBREVIATIONS………………………………………..…….xvi ACKNOWLEDGEMENTS……………………………………….........xviii CO-AUTHORSHIP STATEMENT…...……………….…………….........xix  CHAPTER ONE  INTRODUCTION 1.1 Triple-Stranded Supramolecular Complexes……………………………….…………….......2    1.1.1 General Introduction……………………………………………………………………2 1.1.2 Helicates versus Mesocates------ a Historical Review………………….……………....5    1.1.3 A Review of Triple-Stranded Supramolecular Complexes……………...……………10       1.1.3.1 Oligo(bipyridine)s as Ligands…..........................................................................10       1.1.3.2 Benzimidazole Derivatives as Ligands.................................................................14       1.1.3.3 Imine Derivatives as Ligands…………………………………………...………20       1.1.3.4 Dicatechol Derivatives as Ligands……………………………………...………21 1.2 Dipyrromethene and Poly(dipyrromethene) Ligands……………………………….………26 1.2.1 Dipyrromethenes as Ligands………………………………………………………….26 1.2.1.1 Dipyrromethanes and Dipyrromethenes………………………………………...26 1.2.1.2 Synthesis of Dipyrromethanes………………………………………….……….28 1.2.1.3 Synthesis of Dipyrromethenes…………………………………………..………31 1.2.1.4 Coordination Chemistry of Dipyrromethenes…………………………...………33  iv 1.2.2 Linear Poly(dipyrromethene)s as Ligands…………………………………….………36 1.2.2.1 Synthesis of Bis(dipyrromethene)s………………………….…………………..37 1.2.2.2 Poly(dipyrromethene) Supramolecular Complexes…………….……………….40 1.3 Research Objectives…………………………………………………………………………43  CHAPTER TWO  RESULTS AND DISCUSSION 2.1 Investigations into α-Substituted Bis(dipyrromethene) Ligands…………....……………....47 2.1.1 α,α’-Linked Substituted Bis(dipyrromethene)s……………………….………………47 2.1.1.1 Synthesis of Proligands 158-H2·2HBr – 161-H2·2HBr………………………….47 2.1.1.2 Synthesis of Proligand 165-H2·2HBr……………………………………………50 2.1.1.3 Reactions of Ligands 158 – 161 and 165 with Trivalent Metals……………...52 2.1.2 β,β’-Linked Bis(dipyrromethene)s with α-Positions Substituted…………………..…54 2.1.2.1 Synthesis of Proligands 174-H2·2HBr and 175-H2·2HBr………...………….….54 2.1.2.2 Reactions of Ligands 174 and 175 with Trivalent Metals……………...…….…56 2.1.3 Bis(dipyrromethene)s with Two α-Positions Unsubstituted……………………….….57 2.1.3.1 Synthesis of Proligands 179-H2·2HBr – 181-H2·2HBr………………………….57 2.1.3.2 Reactions of Ligands 179 – 181 with Trivalent Metals…………………….…58 2.1.4 Summary of α-Substituted Bis(dipyrromethene) Ligands………………………….…60 2.2 Synthesis of α-Free β,β’-Linked Bis(dipyrromethene) Ligands………………………….…61 2.2.1 Retrosynthesis……………………….………………………………………………...61 2.2.2 Attempts to Synthesize α-Unsubstituted β,β’-Linked Bis(formylpyrrole)s from Substituted Precursors.......……………………......................63 2.2.3 Synthesis of α-Unsubstituted β,β’-Linked Diformyldipyrromethanes from α-Unsubstituted Pyrrole Derivatives…………...………………………………….65 2.2.3.1 Substrate Selection………………………………………………………………65 2.2.3.2 Synthesis of β,β’-Linked Diformyldipyrromethane 201......................................69 2.2.3.3 Synthesis of meso-Substituted β,β’-Linked     Diformyldipyrromethanes……………………………………………………….…73  v 2.2.4 Synthesis of α-Free β,β’-Linked Bis(dipyrromethene) Proligand 220-H2·2HBr...……78 2.3 Synthesis of Triple-Stranded Helicates and Mesocates Using Ligand 220…………………80 2.3.1 Synthesis of Co3+ and Fe3+ Triple-Stranded Complexes……………………………...80 2.3.2 Synthesis of Triple-Stranded Complexes with Other Trivalent Metals…………….…88 2.4 Attempts to Synthesize a β,β’-Linked α-Fluorobis(dipyrromethene) Ligand………………90 2.5 Synthesis of Triple-Stranded Complexes using    Bis(meso-aryldipyrromethene) Ligands………………………………………………….....92 2.5.1 Synthesis of β,β’-Linked Diacyldipyrromethanes..…………………………………...92 2.5.2 Synthesis of β,β’-Linked Bis(meso-aryldipyrromethene) 250-H2……………….....…95 2.5.3 Synthesis of Triple-Stranded Complexes using Ligand 250………….....…...……….97 2.5.4 Synthesis of Quaternary-Carbon-Bridged     Bis(meso-aryldipyrromethene) 260-H2…………………………………….....………..99 2.5.5 Synthesis of Triple-Stranded Complexes using Ligand 260…………….......……....101 2.5.6 Formation of Helicate versus Mesocate……………………………………….....…..107 2.6 Summary and Conclusion……………………………………………………….....………112 2.7 Future Perspectives……………………………………………………………….....……..114  CHAPTER THREE  EXPERIMENTAL 3.1 General Material and Instrumentation………………………………………....…………..118 3.2 Experimental Procedure and Data…………………………………………....……………120 3.3 Crystal Data……………………………………………………………………....………..165 3.4 NMR Spectra of Selected Compounds……………………………………………....…….193  REFERENCES…………………………………………………………………....……….219   vi LIST OF TABLES  Table 2.1. Observations and results of the reactions of ligands 158 – 161 and 165 with Co3+ / Fe3+…………………...…………....……………….52 Table 2.2. Observations and results of the reactions of ligands 174 and 175 with Co3+ / Fe3+…………………………………....………………...56 Table 2.3. Observations and results of the reactions of ligands  179 – 181 with Co3+ / Fe3+………………………………....……………………...58 Table 2.4. Condensation results of 195 with an aldehyde. ………….....……………………….73 Table 2.5. Condensation results of 195 with an acetal……………………………….....………75 Table 2.6. Selected bond lengths, bond angles and metal distances of 221 and 223……..…….84 Table 2.7. Selected bond lengths, bond angles and metal distances of 222 and 224……...……84 Table 2.8. Complexation of 220 with Co3+, Fe3+, Mn3+, Ga3+ and In3+………………....……...88 Table 2. 9. Reaction conditions and yields for the synthesis of diacyldipyrromethanes…………………………………………………….....……...94 Table 2.10. Complexation of ligand 250 with Fe3+, Co3+, Mn3+, Ga3+ and In3+….……....…….97 Table 2.11. Complexation of ligand 260 with Fe3+, Co3+, Mn3+, Ga3+ and In3+………..…......101 Table 2.12. Selected bond lengths, bond angles and metal distances of 261 – 264…………....104 Table 3.1. Crystal data for 201……………………………………………….....……………..165 Table 3.2.  Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 201…………………………………………………………………………..166 Table 3.3. Crystal data for 202………………………………………………….....…………..167 Table 3.4.  Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 202…………………………………………………………………………..168 Table 3.5. Crystal data for 221…………………………………………….....………………..169 Table 3.6.  Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 221…………………………………………………………………………..170   vii Table 3.7. Crystal data for 222. ………………………………………………….....…………173 Table 3.8.  Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 222…………………………………………………………………………..174 Table 3.9. Crystal data for 223………………………………………………….....…………..175 Table 3.10.  Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 223…………………………………………………………………………..176 Table 3.11. Crystal data for 224…………………………………………….....……………..179 Table 3.12.  Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 224…………………………………………………………………………..180 Table 3.13. Crystal data for 261……………………………………………….....…………..181 Table 3.14.  Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 261…………………………………………………………………………..182 Table 3.15. Crystal data for 262……………………………………………….....…………..184 Table 3.16.  Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 262…………………………………………………………………………..185 Table 3.17. Crystal data for 263…………………………………………….....……………..187 Table 3.18.  Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 263…………………………………………………………………………..188 Table 3.19. Crystal data for 264………………………..……………………….....…………..190 Table 3.20.  Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 264…………………………………………………………………………..191   viii LIST OF FIGURES  Figure 1.1. Absolute configurations of an octahedral metal center: (a) Λ (left-handed) and (b) ∆ (right-handed).………………………………..……..2 Figure 1.2. Representive structure of left-handed helicate and achiral mesocate…………………………………………. ……….....……………….3 Figure 1.3. Proposed structure of [Cu2(1)3]4+ by Harris and McKenzie.……………...…………5 Figure 1.4. Structures of 1, 2-H2 and 3-H2………………………………….....…………………5 Figure 1.5. Structures of 4-H4 – 9-H4………………………………………....………….….…..6 Figure 1.6. “S” versus “C” conformation of ligands with different linker……………....………7 Figure 1.7. Structures of 10 – 13-H4………………………………………….....……….……..8 Figure 1.8. Structures of 14-H4, 15 and 16………………………….....……………………….9 Figure 1.9. Structures of 17, 18 and 19………………………………….....…………………..10 Figure 1.10. Structures of 20 – 27………………………………………….....………………...11 Figure 1.11. Structures of 28 and 29………………………………….....……………….……..12 Figure 1.12. Structures of 30 – 35……………………………………….....…………….……..12 Figure 1.13. Structures of 36, 37 and 38……………………………….....…………………….14 Figure 1.14. Structures of 39, 40 and 41……………………………………….....………….…14 Figure 1.15. Structures of 42 – 49…………………………………………….....………….…..15 Figure 1.16. Structures of 50 – 58…………………………………………….....…………...…17 Figure 1.17. Structures of 59, 60 and 61………………………………….....…………….……18 Figure 1.18. Structures of 62, 63 and 64…………………………….....………………….……19 Figure 1.19. Structures of 65 – 68………………………………………....……………………20 Figure 1.20. Structures of 69, 70 and 71………………………………….....…………….……20 Figure 1.21. Structures of 4-H4, 9-H4, 63, 72-H4 and 73-H4………………...……………...….22 Figure 1.22. Structures of 74-H4 – 80-H4………………………………....………………..…..23 Figure 1.23. Structures of 81-H4, 82-H4 and 83-H4…………………………....…………...…..24 Figure 1.24. Structures of 84-H4 – 87-H4………………………………………....……………24  ix Figure 1.25. Structures of 88-H4 – 95-H4………………………………....………………...….25 Figure 1.26. Representive structures of dipyrromethane isomers……………....……………...26 Figure 1.27. Representive structure of dipyrromethenes……………………....……………….26 Figure 1.28. Structures of 96-H·HCl and 97-H…………………………………....……………33 Figure 1.29. Structures of 100-H·HCl, 101-H·HCl and 102-H…………………....……………34 Figure 1.30. Representive structures of bis(dipyrromethene) isomers………………....………36 Figure 1.31. Structures of 108 – 116………………………………………………….....……...38 Figure 1.32. Structures of starting materials (117 – 122) for the synthesis of bis(dipyrromethene)s……………………………………....…………..38 Figure 1.33. Supramolecular architectures generated from poly(dipyrromethene) ligands………………………………………….....………....40 Figure 1.34. Structures of 126-H2·2HBr – 137-H2·2HBr……………………....……………….40 Figure 1.35. Structures of 138-H2·2HBr – 140-H2·2HBr………………………....…………….41 Figure 1.36. Structure of 143-H2·2HBr. ……………………………………….....…………….42 Figure 1.37. Fluorescent dipyrromethene complexes. ………………………………….....……43 Figure 1.38. Dipyrromethene-complex-linked porphyrin triad. ………………….…….....……43 Figure 1.39. Ruthenium(II) dipyrromethene/bipyridine complexes. ……………………….......44 Firgure 1.40. Space Filling structure of the proposed triple-stranded helicate. ……………......45 Figure 2.1. Structures of 152, 154, 176 and 177………………………………….....………….57 Figure 2.2. Structures of diformyldipyrromethane isomers: 163, 200 and 201………….....…..69 Figure 2.3. 1H NMR spectra of 201(a) and 163(b) in d6-DMSO………………….....…………70 Figure 2.4. ORTEP structure of 201………………………………………....…………………70 Figure 2.5. ORTEP structure of 202………………………………………....…………………72 Figure 2.6. 1H NMR spectrum of Co2L3 (221)……………………………………....…………82 Figure 2.7. 1H NMR spectrum of Co2L3 (222)…………………………………....……………82 Figure 2.8. ORTEP structures of triple-stranded complexes: Co2L3 helicate 221 (a), Co2L3 mesocate 222 (b), Fe2L3 helicate 223 (c), and Fe2L3 mesocate 224 (d)…………………..…………….83  x Figure 2.9. Optical absorption spectra of 221 – 224 in chloroform…………………………….86 Figure 2.10. ORTEP structures of helicates 261 (a), 262 (b), 263 (c) and 264 (d). Phenyl groups and hydrogens are omitted for clarity……..………....………….103 Figure 2.11. Optical absorption spectra of the helicates 261 – 264 in chloroform……………105 Figure 2.12. VT 1H NMR of In3+ complexes 227 in d-chloroform………...………....………108 Figure 2.13. VT 1H NMR of In3+ complexes 255 in d4-1,2-dichlorobenzene…………...……108 Figure 2.14. Top views of the Λ configuration (a), Bailar twist intermediate (b) and ∆ configuration (c) for the reported hydroxypyridinone coordinationunit……………....…………….109 Figure 2.15. Top views of the postulated Ray-Dutt twist intermediate (a), ∆ configuration (b) and postulated Bailar twist intermediate (c) of the dipyrromethene coordinationunit…………………………………....……..109 Figure 2.16. Representive structures of polyhedron supramolecule cages……………….......114 Figure 2.17. Representive structures of porphyrin and N-confused porphyrins…………........115 Figure 3.1. 1H NMR spectrum of 155 in d6-DMSO…………………………....……………..193 Figure 3.2. 13C NMR spectrum of 155 in d6-DMSO………………………………....……….193 Figure 3.3. 1H NMR spectrum of 159-H2·2HBr in CDCl3/CD3OD………………....………...194 Figure 3.4. 13C NMR spectrum of 159-H2·2HBr in CDCl3/CD3OD…………….....………….194 Figure 3.5. 1H NMR spectrum of 173 in d6-DMSO…………………………....……………..195 Figure 3.6. 13C NMR spectrum of 173 in d6-DMSO……………………………....………….195 Figure 3.7. 1H NMR spectrum of 175-H2·2HBr in CDCl3/CD3OD………………....………...196 Figure 3.8. 13C NMR spectrum of 175-H2·2HBr in CDCl3/CD3OD……………….....……….196 Figure 3.9. 1H NMR spectrum of 181-H2·2HBr in CDCl3/CD3OD………………....………...197 Figure 3.10. 13C NMR spectrum of 181-H2·2HBr in CDCl3/CD3OD…………….....………...197 Figure 3.11. 1H NMR spectrum of 193 in d6-DMSO……………………………....…………198 Figure 3.12. 13C NMR spectrum of 193 in d6-DMSO……………………….....……………..198 Figure 3.13. 1H NMR spectrum of 201 in d6-DMSO…………………………....……………199 Figure 3.14. 13C NMR spectrum of 201 in d6-DMSO………………………....……………...199  xi Figure 3.15. 1H NMR spectrum of 202 in d6-DMSO…………………………....……………200 Figure 3.16. 13C NMR spectrum of 202 in d6-DMSO…………………………....…………...200 Figure 3.17. 1H NMR spectrum of 203 in d6-DMSO…………………………....……………201 Figure 3.18. 13C NMR spectrum of 203 in d6-DMSO………………………....……………...201 Figure 3.19. 1H1H COSY spectrum of 203 in d6-DMSO……………………....……………. 202 Figure 3.20. 1H NMR spectrum of 220-H2·2HBr in CD3OD……………….....………………203 Figure 3.21. 13C NMR spectrum of 221 in CD2Cl2………………………….....…………….. 204 Figure 3.22. 13C NMR spectrum of 222 in CD2Cl2……………………………….....……….. 204 Figure 3.23. 1H NMR spectrum of 223 in CD2Cl2…………………………….....……………205 Figure 3.24. 1H NMR spectrum of 224 in CD2Cl2…………………………….....……………205 Figure 3.25. 1H NMR spectrum of 226 in CD2Cl2……………………………….....…………206 Figure 3.26. 1H NMR spectrum of 227 in CD2Cl2……………………………….....…………206 Figure 3.27. 1H NMR spectrum of 236 in d6-acetone……………………….....…………….. 207 Figure 3.28. 13C NMR spectrum of 236 in d6-acetone………………………….....…………. 207 Figure 3.29. 1H NMR spectrum of 237 in d6-acetone……………………………….....…….. 208 Figure 3.30. 13C NMR spectrum of 237 in d6-acetone…………………………….....………. 208 Figure 3.31. 1H NMR spectrum of 238 in d6-acetone……………………….....…………….. 209 Figure 3.32. 13C NMR spectrum of 238 in d6-acetone…………………….....………………. 209 Figure 3.33. 1H NMR spectrum of 248 in d6-acetone………………………….....…………..210 Figure 3.34. 13C NMR spectrum of 248 in CD2Cl2……………………….....……………….. 210 Figure 3.35. 1H NMR spectrum of 250 in CD2Cl2………………………….....………………211 Figure 3.36. 13C NMR spectrum of 250 in CD2Cl2………………………….....…………….. 211 Figure 3.37. 1H NMR spectrum of 252 in CD2Cl2………………………….....………………212 Figure 3.38. 1H NMR spectrum of 255 in CD2Cl2………………………….....………………212 Figure 3.39. 1H NMR spectrum of 257 in CDCl3………………………….....……………… 213 Figure 3.40. 13C NMR spectrum of 257 in CDCl3………………………….....………………213 Figure 3.41. 1H NMR spectrum of 259 in CD3CN……………………………....……………214 Figure 3.42. 13C NMR spectrum of 259 in CDCl3………………………….....………………214  xii Figure 3.43. 1H NMR spectrum of 260 in CD2Cl2……………………….....…………………215 Figure 3.44. 13C NMR spectrum of 260 in CD2Cl2……………………….....……………... 215 Figure 3.45. 1H NMR spectrum of 262 in CD2Cl2……………………….....…………………216 Figure 3.46. 13C NMR spectrum of 262 in CD2Cl2…………………….....………………….. 216 Figure 3.47. 1H NMR spectrum of 264 in CD2Cl2…………………….....……………………217 Figure 3.48. 13C NMR spectrum of 264 in CD2Cl2…………………….....………………….. 217 Figure 3.49. 1H NMR spectrum of 265 in CD2Cl2………………………….....………………218 Figure 3.50. 13C NMR spectrum of 265 in CD2Cl2………………………….....…………….. 218  xiii LIST OF SCHEMES  Scheme 1.1. Tautomerization of dipyrromethene.……………………………….....………..…27 Scheme 1.2. Synthesis of symmetrically substituted dipyrromethanes………………….......….28 Scheme 1.3. Synthesis of unsymmetric dipyrromethanes…………………………….....…...…28 Scheme 1.4. Condensation of pyrrole and an aldehyde……………………..............…….……29 Scheme 1.5. Stepwise synthesis of meso-substituted dipyrromethanes……………....………...29 Scheme 1.6. Synthesis of β,β’-linked dipyrromethanes from pyrrole and an aldehyde.……………………………………....………………30 Scheme 1.7. Synthesis of substituted dipyrromethenes……………………………....………...31 Scheme 1.8. Synthesis of meso-substituted dipyrromethenes by oxidation………….....………32 Scheme 1.9. Deprotonation of dipyrromethene……..…………………….…....……………….33 Scheme 1.10. Formation of coordinatively unsaturated octahedral complex 99…...…………..34 Scheme 1.11. Formation of octahedral complex 104……………..….……….....……………...35 Scheme 1.12. Routes to bis(dipyrromethene)s……………………………….....………………37 Scheme 1.13. Synthesis of proligand 107-H2·2HBr………………………………....………….37 Scheme 1.14. Synthesis of proligand 126-H2·2HBr………………………………....………….39 Scheme 1.15. Synthesis of the triangular helicate 142………………………..…….....………..42 Scheme 2.1. Synthesis of proligands 158-H2·2HBr – 161-H2·2HBr……………….....………48 Scheme 2.2. Synthesis of proligand 166-H2·2HBr………………………………....…………...50 Scheme 2.3. Synthesis of proligands 174-H2·2HBr and 175-H2·2HBr……………….....……55 Scheme 2.4. Synthesis of proligands 179-H2·2HBr – 181-H2·2HBr……………….....………58 Scheme 2.5. Retrosynthesis of α-free β,β’-linked bis(dipyrromethene)s……………..…....…...61 Scheme 2.6. Demethylation of pyrroles through decarboxylation………………….....………..63 Scheme 2.7. Proposed synthesis of α-unsubstituted bis(formylpyrrole)s 186 and 187 from 172 and 173…………………………………………....………...63 Scheme 2.8. Bromination of pyrrole and α-carbonylpyrroles……………….....……………….65 Scheme 2.9. Condensation of pyrrole ester 188 with 2-nitrobenzaldehyde…………….....……66  xiv Scheme 2.10. Condensation of pyrrole 192 with dimethoxymethane……………………....…66 Scheme 2.11. Condensation of pyrrole 194 with dimethoxymethane………………....………67 Scheme 2.12. Halogenation of 195. …………………………………………………....………68 Scheme 2.13. Condensation of 195 with dimethoxymethane…………………………....……..69 Scheme 2.14. Proposed formation mechanism of 202…………………………....…………….71 Scheme 2.15. Synthesis of acetals 207 – 211…………………………………….....…………..74 Scheme 2.16. Synthesis of α-free proligand 220-H2·2HBr…………………...…….....………..78 Scheme 2.17. Synthesis of Co3+ and Fe3+ triple-stranded bis(dipyrromethene) complexes………………………………………….....……….80 Scheme 2.18. Attempted synthesis of α-fluorobis(dipyrromethene) ligand 234………….....….90 Scheme 2.19. Retrosynthesis of bis(meso-aryldipyrromethene) ligands.……......……………..92 Scheme 2.20. Synthesis of diacyldipyrromethanes……………………………....……………..92 Scheme 2.21. Reduction of diacyldipyrromethanes…………………………….....……………95 Scheme 2.22. Synthesis of β,β’-linked bis(meso-aryldipyrromethane)s……………….....…….95 Scheme 2.23. Oxidation of β,β’-linked bis(meso-phenyldipyrromethane) 248…………….......96 Scheme 2.24. Synthesis of quaternary-carbon-bridged diacyldipyrromethanes…………....…..99 Scheme 2.25. Synthesis of quaternary-carbon-bridged proligand 260-H2…………….....……100 Scheme 2.26. The interconversion between “C” and “S” conformation of bis(dipyrromethene) ligand…………………………………………….....………..110 Scheme 2.27. Formation of helicate versus mesocate…………………….....………………..111 Scheme 2.28. Synthetic route to proposed ligands…………………………….....……………114    xv LIST OF ABBREVIATIONS  Ac acetyl Ar aryl BINOL 1,1'-bi-2-naphthol Bn benzyl BODIPY boron-dipyrromethene br broad Calcd calculated d doublet dd doublet-boublet DCTB 2-[(2E)-3-(4-tert-butylphenyl)-2-methylprop-2-enylidene] malononitrile CD circular dichroism COSY correlation spectroscopy DDQ 2,3-dichloro-5,6-dicyanobenzoquinone DMF N, N-dimethylformamide DMSO dimethylsulfoxide DNA deoxyribonucleic acid EI eletron impact ionization ESI electrospray ionization h hour(s) HHH head-head-head HHT head-head-tail HPLC high performance liquid chromatography HRMS high resolution mass spectroscopy LMCT ligand-to-metal charge transfer  xvi IUPAC International Union of Pure and Applied Chemistry m multiplet MALDI-TOF matrix-assisted laser desorption/ionization-time of flight m/e mass/charge min minute(s) MOM methoxymethyl MS mass spectroscopy NCP N-confused porphyrin NFSI N-fluorobenzenesulfonimide NIS N-iodosuccinimide nm nanometer(s) NMR nuclear magnetic resonance ORTEP Oak Ridge thermal ellipsoid plot Ph phenyl ppm part per million ROESY rotating-frame nuclear Overhauser effect spectroscopy r. t. room temperature s singlet t triplet TEA triethylamine TFA trifluoroacetic acid THF tetrahydrofuran TIPS triisopropylsilyl TLC thin-layer chromatography VT NMR variable temperature nuclear magnetic resonance UV-vis ultraviolet-visible  xvii ACKNOWLEDGEMENTS  Thank you to my supervisor, Dr. David Dolphin for constructive guidance, advice and support in my pursuit of a Doctorate of Philosophy. Your profound scientific knowledge and great sense of humor were a source of growth, both academically and socially. Thank you to lab-mates particularly Mr. Andrew Tovey for valuable advice and kind proof-reading of my papers and this dissertation, Dr. Lingyun Zhang for generous offer of personal assistance, my peers, Miss Qing Mao, Mr. Li ma and Mr. Yunchang Liu for sharing such enormous academic growth in the past six years, and Dr. Ji-Young Shin for assistance with experimental techniques. Thank you to Dr. Brian Patrick for all of the crystallography analysis, Dr. Yun ling and Mr. Marshall Lapawa for microanalysis, Dr. Paul Xia, Ms. Maria Ezhova and Ms. Zorana Danilovic for assiatance with NMR spectroscopic analysis. Thank you to staff of chemstore, mechanical engineering, electronic engineering, glassblowing shop and main office for services provided. Thank you to my tennis fellows, especially Dr. Hui Wang, Dr. Yaquen Chen and Dr. Yi Cao for the great fun we had. Thank you to my English teacher, Mrs. Vera Burnham for all the wonderful lessons you delivered. Last but not least thank you to my family, especially my parents and my wife Xiufeng for unconditional support and love and for always being my joy and source of motivation.  xviii CO-AUTHORSHIP STATEMENT  This project was initiated by my supervisor, Prof. Dr. David Dolphin. In the early stages, PDF Dr. Ji-Young Shin provided helpful discussion and suggested the investigation into ligands with long side chains. Through the literature search and preliminary investigation, I identified the crucial aspects of the project. From this point, I designed, synthesized and characterized the key precursors and the α-free β,β’-linked ligands which eventually led to the desirable triple-stranded supramolecules. Through all stages of the project, Dr. Dolphin has provided crucial guidance and suggestions. The work has produced two published papers with another manuscript yet to be published. I prepared the first version of each of the manuscripts. Dr. Ji-Young Shin provided useful suggestions for the first paper and Dr. Dolphin assisted in the preparation and revision of all manuscripts.   xix      CHAPTER ONE:  INTRODUCTION  - 1 - 1.1 Triple-Stranded Supramolecular Complexes 1.1.1 General Introduction A helix is a fascinating and elegant structural motif which has captivated chemists ever since the discovery of the double helical structure of deoxyribonucleic acid (DNA). Among the numerous helical compounds, discrete triple-stranded supramolecular complexes have attracted particular attention over the last few decades because they are of great importance for the development and understanding of supramolecular chemistry relating to aspects of molecular recognition and chirality control.1-3 Explorations in this field have recently led to the development of some triple-stranded systems that have promising applications. For instance, Hannon’s group has reported that certain Ruthenium triple-stranded helicates bind DNA and exhibit interesting activity against cancer cell lines,4 and Vandevyver et al. have developed a family of luminescent lanthanide triple-stranded helicates which are potential cellular-imaging probes.5 M Λ=Μ M ∆=P (a)                                               (b) Figure 1.1. Absolute configurations of an octahedral metal center: (a) Λ (left-handed) and (b) ∆ (right-handed). Triple-stranded supramolecular complexes can be structurally categorized according to the manner in which the strands are arranged. Take the simplest octahedral dinuclear triple-stranded  - 2 - M2L3 complexes for example. Since each metal center can be either left-handed (Λ) or right-handed (∆) (Figure 1.1), a M2L3 complex may exhibit one of three configurations: ΛΛ, ∆∆ and Λ∆. A complex with either ΛΛ or ∆∆ configuration is homochiral. Because the strands wind helically (Figure 1.2), such a complex is termed helicate. The ΛΛ and ∆∆ complexes are left-handed (M-) and right-handed (P-) helicates, respectively. As enantiomers, the M- and P-helicates are generated as a racemic mixture when a nonchiral ligand is employed. On the other hand, since the Λ∆ complex has two opposite chiral centers, the strands wind in a side-by-side manner generating a complex with a mirror plane. Corresponding to the term rac, the achiral Λ∆ complex is termed mesocate (also called meso-helicate6 or side-by-side helicate7). Figure 1.2. Representive structure of left-handed helicate and achiral mesocate. In the cases of complexes where the number of metal centers (n) is greater than 2, the strands are primarily arranged in three ways: helically, side-by-side and irregularly, leading to homo (ΛΛΛ… or ∆∆∆…), alternate (Λ∆Λ…) and irregular configurations (∆∆Λ…, for example), respectively. Obviously, all the helical complexes (helicates) are chiral. The chirality of side-by-side complexes, however, depends on the number n. When n is odd, chiral complexes are expected; when n is even, the side-by-side arrangement leads to achiral mesocates. The chirality of an irregular arrangement is rather complicated and either chiral or achiral complexes can be generated.  - 3 - Triple-stranded supramolecular complexes can also be categorized according to the type of metal or strand. Triple-stranded helicates possessing identical metal ions are referred to as homometallic helicates. Conversely, when the metal ions of a helicate are different, the helicate is heterometallic. Similarly, helicates containing identical strands are homoleptic (or homostrand) and helicates possessing different strands are heteroleptic (or heterostrand). Moreover, the strands themselves can be either homotopic or heterotopic. Homotopic strands lead to helicates which have no directionality whereas heterotopic strands result in helicates in which the strands can orient themselves in either parallel (head-head-head or HHH) or antiparallel (head-head-tail or HHT) fashion.    - 4 - 1.1.2 Helicates versus Mesocates------a Historical Review  Figure 1.3. Proposed structure of [Cu2(1)3]4+ (by Harris and McKenzie). Helicates and mesocates are the most important architectures for triple-stranded supramolecular complexes. As possible products of the same reaction, they are competitive with each other. The formation of mesocate versus helicate has been an important topic in the history of triple-stranded complexes. H N H N O N OH O N H H N N OH O N OH O O O H H NN N N O NO OH 1 2-H2 Figure 1.4. Structures of 1, 2-H2* and 3-H2*.  “L-Hn·xHBr”). 3-H2   *These compounds coordinate with metals in the deprotonated form and thus are proligands. In this dissertation, the ligands, not the proligands are numbered for convenience. Accordingly, the proligands are denoted as “L-Hn” (or  - 5 - Examples of triple-stranded complexes were known as early as the 1950s,8-10 but the structures were unclear at that time. In 1969, Harris and McKenzie reported a dinuclear com ration. Based on this, the authors proposed a right-handed helical structure for these complexes. Later, using 3-H2, a synthetic analogue of 2-H2, the group ma e field of helicates rapidly expanded. Numerous triple-stranded helical systems were develope oligo(bipyridine), imine deriva echol, bis(1,3-dicarbonyl) and plex [Cu2(1)3]4+ and suggested that such a complex could exist as three isomers (in their notation, (+)(+), (-)(-) and (+)(-)).11 Although the structure was not fully characterized, it was proposed that a dinuclear M2L3 complex might take a homochiral helical structure. Such a proposal was supported by the 1970s work of Raymond who prepared the dinuclear Fe3+, Al3+ and Cr3+ complexes with Rhodoturulic acid 2-H2,12 a naturally occurring siderophore. Circular dichroism (CD) studies showed that both the octahedral metal centers of the Fe223 complex were in ∆ absolute configu de another Fe3+ complex Fe233 of which the triple-stranded helical structure was proven by X-ray crystallographic analysis.13  During the 1980s and 1990s, th d with diverse types of ligands such as tives, benzimidazole derivatives, dicat  8-hydroxyquinoline derivatives.2,3 (CH2)n HO OH HO OH n=0    4-H4        n=1    5-H4 n=2    6-H4        n=3    7-H4 n=4 8-H4 n=6 9-H4 Figure 1.5. Structures of 4-H4 – 9-H4.  - 6 - It was not until 1995 that the first mesocate was synthesized from a dicatechol ligand 7 by Albrecht and Kotila.6 To explore the factors controlling the diastereoselectivity of helicate versus mesocate, the group investigated a series of dicatechol ligands 4 – 9 (Figure 1.5).6,14-20 It was found that all the ligands possessing a linker with an even number of carbon atoms led to helicates and ligands having a linker with an odd number of carbon atoms generated mesocates (odd-even rule). Noticing the ligands adopt “S” conformation in D3 helicates and “C” conformation in C3h mesocates, the authors proposed that the length of the alkyl linker would affect the conformation of the ligands and eventually determine the structure of the complexes.6,19,21 For example, ligands having an ethylene linker prefer the “S” conformation (Figure 1.6) possess the which facilitates the helical structure while ligands with methylene linkers  “C” conformation and will result in mesocates. helicate mesocate "S" conformation  "C" conformation Figure 1.6. “S” versus “C” conformation of ligands with different linker. Besides the dicatechol ligands, the empirical odd-even rule is also applicable to some types of ligands with alkyl linkers. For instance, bis(bipyridine) ligand 10 led to a mesocate upon coordination with Fe2+ whereas ligand 11 generated a helicate with the same ion.21  To understand the racemization of homochiral helicates, Raymond investigated the interconversion between dinuclear triple-stranded ΛΛ and ∆∆ helicates. It was found that under  - 7 - basic conditions, a ∆∆ isomer can convert into ΛΛ isomer through a nondissociative Bailar twist.22 Surprisingly, the racemization energy barriers of [Ga2133]6- and the related mononuclear [Ga123]3- were very similar, indicating the conversion of the ∆∆ (orΛΛ) helicate to the ΛΛ (or∆∆) helicate was not accom of both metal centers but step plished by simultaneous inversion wise inversion via an intermediate---∆Λ mesocate. Although the high energy mesocate was not isolated, the studies indicated that a helicate and mesocate might interconvert under certain conditions. N N N N N N N N HN OO NH NHHN OHHO OO OHHOOHHO O HNNH O 10 11 2  e (NMR) Spectroscopy.23 The variable temperature NMR showed the two isomers were in thermodynamic equilibrium, with lower temperatures favouring the mesocate. However, the presence of H2O, as guest, remarkably stabilized the helicate and shifted the system completely to the helicate. Similar phenomena were also observed by another group in the cases of the bis(bipyridine) ligands 15 and 16.24 NMR 12-H 13-H4 Figure 1.7. Structures of 10 – 13-H4. In 1999, Raymond reported the observation of both the helical and meso forms of Ga2143 in d6-DMSO using 1H Nuclear Magnetic Resonanc  - 8 - spectroscopy showed that [Fe2153]4+ and [Fe2163]4+ existed as a mixture of the helical and meso forms in a ratio of 1 : 2 in d6-DMSO at 25 ℃. Addition of Cl- led to predominant formation of the helicates. Since both a mesocate and helicate existed in the same environment, these cases challenged the odd-even rule. Based on the observations and the studies on the racemization of helicates, Raymond suggested that a helicate and the diastereomeric mesocate can interconvert through an nondissociative Bailar twist and whether a helicate or mesocate will be formed is under thermodynamic rather than kinetic control.23 N H N H OO N N N N N H N H OO N N N N H N O N OH O N H N O OH O 14-H2 15 16 Figure 1.8. Structures of 14-H2, 15 and 16. In recent years, many examples have provided valuable insight into the formation of triple-stranded helicates versus mesocates. However, the mechanism determining the formation of helicates versus mesocates is not yet fully understood.  - 9 - 1.1.3 A Review of Triple-Stranded Supramolecular Complexes Since the first report of triple-stranded complexes in 1950s,8-10 numerous triple-stranded helicates and mesocates have been developed using various types of ligands. The most prevalent ligands include oligo(bipyridine)s, benzimidazole derivatives, imine derivatives and dicatechols.  1.1.3.1 Oligo(bipyridine)s as Ligands Because the sp2-hybridized nitrogen on a pyridine ring is an excellent electron donor, 2,2’-bipyridine 17 (Figure 1.9) is an important building block for ligands used in supramolecular chemistry. However, due to steric hindrance, 6,6’-substituted ligands cannot generate octahedral triple-stranded complexes although they are excellent ligands for double helicates. Rather, ligands with substituents at the 4- or 5-positions lead to triple-stranded helicates or mesocates. N N 17 1 2 3 4 5 6 N N N N N N N N N N 18 19  Figure 1.9. Structures of 17, 18 and 19. Oligo(bipyridine) ligands having alkyl linkers at the 5-position usually follow the odd-even rule upon the formation of triple-stranded complexes. As mentioned in 1.1.2, the coordination of ligand 10 with Fe2+ selectively formed the mesocate [Fe2103]4+ while ligand 11 generated the helicates.21 The proton signal(s) of the linker CH2 in the NMR spectra can be used to identify the structure because the two hydrogens are homotopic in a D3 structure but diastereotopic in a C3h  - 10 - structure. Although an X-ray structure of [Fe2103]4+ was not obtained, the occurrence of two doublets for the CH2 group unambiguously showed that [Fe2103]4+ existed in the meso form in solution. Similarly, the meso structure of [Fe2183]4+ was confirmed by NMR as well.1 The ethylene-linked ligand 19, on the other hand, produced a trinuclear triple-stranded helicate [Ni3193]6+. Interestingly, partial spontaneous resolution occurred upon crystallization and different CD values were obtained from different crystals.25 NH O NN N N X NN X=  ---       20           X=CH2       21 2 X=(CH2)4  24           X=O           25 X=S 27 HN X=(CH2)2  22           X=(CH )3   23 O NN 26 Figure 1.10. Structures of 20 – 27. Ligands 20-26 (Figure 1.10) synthesized by Elliott and co-workers26-28 have the linker at the 4-position. Although complexes [Fe2203]4+, [Fe2223]4+ and [Fe2243]4+ were found to possess a hel 2273]4+ was found to exist in the helical form, both in the solid state and in solution.31 It was suggested that the presence of heteroatoms makes the propylene group able to ro rmational distortion of the cha ical structure as expected, ligands such as 21, 23, 25, and 26, having a linker with an odd number of CH2 unit(s), also led to helicates with Fe2+.29,30  The amide group is another popular type of linker in addition to alkyl chains. Although 27 possesses a propylene as the linker, complex [Fe tate more freely and leads to a confo in which favours the helical structure.  - 11 - NN N N N N O HN NH O N N 28 29  Figure 1.11. Structures of 28 and 29. To selectively form enantiomeric helicates using bipyridine ligands, two types of chiral ligands have been introduced. One manner is to introduce chiral substituents to the coordination units. For example, pinene derivative 28 (Figure 1.11) generated right-handed helicates [Fe2283]4+, [Cd2283]4+ and [Zn2283]4+ with Fe2+, Cd2+ and Zn2+, respectively.32 Another chiral ligand 29 also led to a right-handed helicate [Fe2293]4+ of which the structure was confirmed by X-ray structural analysis.33 NN X N N X= MOMO MOMO NH HN O O NH HN O O O O H H O O O O N N N N N H H N H C3 CH3 CH3 CH3 O O 33           34 35 30                                   31 32 Figure 1.12. Structures of 30 – 35.   - 12 - The other way to form enantiomeric helicates is to introduce a chiral linker. Ligand 30 (Figure 1.12), synthesized from (S,S) or (R,R)-1,3-diaminocyclohexane, confered helicity to the metal centers of Fe2+, Co3+, Cd2+ and Zn2+.34 CD spectroscopy indicated that the (S,S)-ligand favoured the triple-stranded M-helicate while the (R,R)-ligand had a preference for the P-helicate. However, although the P- or M-helicates were the predominant products, other diastereomers were also found at room temperature, indicating this self-assembly process was not stereospecific. Similarly, enantiomerically pure ligand 31 also predominantly yielded helical isom  by CD spectroscopic measurements because of the overlapping signals from the BINOL component,  X-ray analysis determined that [Zn2323]4+ was a P-helicate.36 Ligand 33,37 having a D-isomannide group in the linker, also reacted with Fe2+ in a enantioselective manner. NMR, ROESY and CD spectroscopy indicated that only M-helicate is formed from 33. However, introduction of chiral groups to the linker does not always work well. Ligands 34 and 35,38 which have Tröger’s base as linker, produced complicated mixtures upon coordination with Fe2+ and Zn2+. Therefore, the introduction of chiral groups to the ligand cannot guarantee that the process of self-assembly proceeds stereoselectively. ers with Fe2+, Co3+and Cd2+.35 Compared to 30 and 31, ligand 32 has a more rigid chiral linker. With Zn2+, ligand 32 selectively formed enantiomerically pure [Zn2323]4+ as evidenced by NMR spectroscopy. Although the absolute configuration could not be determined  - 13 - 1.1.3.2 Benzimidazole Derivatives as Ligands N NN N R N N N N R R NN N R O R' 36                   37         38 Figure 1.13. Structures of 36, 37 and 38. 2-(2’-Pyridyl)benzimidazole derivatives, developed by Piguet and co-workers, are another prevalent N-donor ligand set used to construct triple-stranded complexes. The coordination units of benzimidazole ligands usually consist of one of the three forms: 36, 37, 38 (Figure 1.13), which are generally linked to one another via methylene groups. Probably because of the rigidity of these ligands, all the triple-stranded complexes synthesized from such ligands to date are helicates, which fall into three categories according to the coordination number of the metal centers. N N N N N N N N N N N N N N N N N N 39                                   40                                 41 Figure 1.14. Structures of 39, 40 and 41. a. Six-Coordinate Helicates. The coordination units of ligands 39 – 4139-43 (Figure 1.14) are bidentate 36. Therefore, these ligands can produce triple-stranded helicates upon coordination with ions such as Fe2+ and Co2+ which prefer an octahedral geometry. Through oxidation,  - 14 - triple-stranded helicate [Co2403]6+ was also obtained from helicate [Co2403]4+.40,41 Since [Co2403]6+ is kinetically stable, the authors were able to separate the two enantiomer, M- and P-[Co2403]6+ by chiral resolution on ion exchange resin. A subsequent reduction of P-[Co2403]6+ produced the labile P-[Co2403]4+. N N N N R R N N N N N N N N N N N N R1 R1 N N N N N N R R O N O N X X OH O OH O 42 R=H, X=Br 46 R=CH3, X=H  43 O R=C2H5, X=H R=H, X=Cl 44 45 O CH33 R =C H , R2= R2 R 1 2 5 R2=H R1= R2=H R1=CH3, O CH33 48 2 R= , O 47 49 O  Figure 1.15. Structures of 42 – 49. b. Nine-Coordinate Helicates. Since all the coordination units are tridentate 37 or 38, ligands 42 – 49 (Figure 1.15) can yield triple-stranded complexes with lanthanide ions which favour nonacoordination.5,44-52 X-ray crystallographic analysis showed complexes [Eu2423]6+,44,45 [Tb2443]6+and [Ln2473]6+ (Ln = Eu, Tb, Yb)48-50 all possessed a helical structure. Interestingly, these lanthanide triple-stranded complexes, especially [Ln2L3]6+ (L = 43 – 49), are highly luminescent. By introducing halogens to ligands 45 and 46, the photophysical properties of the  - 15 - corresponding helicates can be tuned.51 Ligands 47 – 49 bear carboxylic acid groups and thus can form water-soluble triple-stranded helicates [Ln2483]6+ and [Ln2493]6+.5,52 The self-assembly mechanism of the formation of lanthanide triple-stranded helicates was studied using [Eu2L3]6+ (L = 42, 44 and 47) as a model. Kinetic investigations showed that an unsaturated double stranded helicate [Eu2L2]6+ is the key intermediate for the formation of [Eu2L3]6+. Depending on the experimental conditions, the [Eu2L2]6+ complex can be formed through either [EuL2]3+ or [Eu2L]6+. Once the key intermediate is formed, a fast and efficient wrapping of the third strand leads to the helicate [Eu2L3]6+.46,47 In the case of heterotopic ligands such as 50 – 58 (Figure 1.16) which contain both types of tridentate units 37 and 38, directionality will be introduced during the formation of triple-stranded helicates. In addition, due to the difference of the coordination units, heterometallic helicates stand a good chance of being generated from this type of ligands.53-57 When ligand 50 was treated with La3+, NMR signals of both paralll HHH (head-head-head) and antiparallel HHT (head-head-tail) species were observed.54,55 Amazingly, when the same ligand was reacted with a mixture of La3+ and Lu3+ in 1 : 1 : 3 ratio of La : Lu : 50, only one major species HHH [LaLu503]6+ was formed. The HHH structure of helicate [LaEu503]6+ was unambiguously confirmed by X-ray crystallography. Similarly, HHH LaEu, LaTb, PrEr, and PrLu heterometallic helicates of ligand 52 were also synthesized. In all cases, the 37-type coordination units were found bound to the smaller lanthanide ions, making the ligands highly-ordered upon coordination. Moreover, the directional selectivity increased with increasing difference in ionic radius of the lanthanide ions. The selectivity can also be affected by the nature  - 16 - of the substituents on the pyridine ring. For example, diethylamine-substituted 55 generated both HHH and HHT heterometallic helicates while chlorine-substituted 56 led to high yields of HHH heterometallic helicates. However, the effect of substituents on selectivity is complicated. The substituents on ligands 57 and 58 seemed to have a different effect from those on ligands 55 and 56.51,56,57 N N N N N N N N R O OCH3 OCH3 N N N N N N N N R O R=N(C2H5)2 R=OH R=N(C2H5)2 R=OCH3 R=OH N N N N N N N N R O N N N N N N N N R O RR 50 51 54 52 53 5 R=N(C2H5)2 R=Cl 55 6 R=N(C2H5)2 R=Cl 57 58 Figure 1.16. Structures of 50 – 58. Ligands 59 – 61 (Figure 1.17) bear more than two binding sites and thus are candidates for synthesizing linear multinuclear helicates.58-63 Coordinated with Eu3+, ligands 59 and 61 formed  - 17 - a homometallic trinuclear and a tetranuclear triple-stranded helicate, respectively.58,59,61 Although the saturated species [Eu4613]12+ was the dominant product, coordinatively unsaturated [Eu3613]9+ (when the ligand was in excess) and [Eu4612]6+ (when the metal was in excess) were also generated. However, w was used, a mixture of hom hen more than one type of lanthanide ometallic and heterometallic helicates was generated.62,63 Once again, 38-type coordination units were found to favour larger ions, which, to some extent, can help increase reaction selectivity. NN N N N N N N N N N NN OCH3 OCH3 NN H3CO H CO3 NN N N N H N N N N N N O NN O 59 61N N N N N NN N N N N N N N O N N NO N 60  Figure 1.17. Structures of 59, 60 and 61  - 18 - c. Helicates Containing Units with Different Coordination numbers. A shared characteristic of ligands 62 – 64 (Figure 1.18) is that they possess both bi- and tridentate coordination units. Therefore, these ligands can form triple-stranded heterometallic helicates based on the fact that the bidentate units bind to octahedral main group or d-block transition metals and the tridentate units coordinate with f-block metals. The major advantage of these ligands is that they can generate selectively HHH heterometallic helicates which are attractive models of energy transfer between d- and f-block metals.64-67 Some of the triple-stranded heterometallic helicates (for example, [ZnEu623]5+, [CoLa633]5+, [RuLu633]5+, [ZnEuZn643]7+) were characterized by X-ray crystallography. The photo- and electrochemistries of these helicates are still under study. OCH3 N N N N N N N N N N N N N N N O NN N N N N N N N N N 62 OCH3 63 64 Figure 1.18. Structures of 62, 63 and 64.   - 19 - 1.1.3.3 Imine Derivatives as Ligands The advantage of imine-based ligands is that they are inexpensive and easy to synthesize. For example, ligand 1 which was used for the synthesis of the triple-stranded complex [Cu2(1)3]4+ in the 1960s can be easily prepared by the condensation of 2-pyridinecarbaldehyde and ethylenediamine.11 X N N N N X N NHN N N NH X=CH2,    65 X=O         66 X=O         68 Figure 1.19. Structures of 65 – 68. The imine/pyridine ligands 65 and 66 (Figure 1.19) produced triple-stranded helicates [Ni2653]4+, [Ni2663]4+ and [Co2663]4+ with the corresponding ions.68,69 Interestingly, the triple-stranded helicates [M2653]4+ (M = Fe, Ru) were found able to bind noncovalently in the major groove of DNA.70 Helicate [Ru2653]4+ even showed activity against cancer cell lines.4 The imine/imidazole ligands 67 and 68 also formed triple-stranded helicates upon coordination with Fe2+. These dinuclear triple helicates, especially [Fe2683]4+ exhibited attractive high spin to low spin crossover behaviour.71,72  X=CH2,    67  N R N N R R R R N N N N N N N N N R R=H             69 Figure 1.20. Structures of 69, 70 and 71. R=CH3         70 R=NH2        71  - 20 - Intriguingly, ligands 69 and 70 can not only form octahedral triple-stranded helicates with e2+ but also five-coordinate triple-stranded helicates with Ag+.73,74  As a lengthened ligand d a tetranuclear helicate with Cu2+.74  inating with metal ions such as Ti4+, V4+, Fe3+, Al3+ and Ga3+, dicatechol ligands can form either helicates or me F with multiple coordination units, 71 generate  1.1.3.4 Dicatechol Derivatives as Ligands Dicatechol derivatives are the most important O-donor ligands used in the self-assembly of triple-stranded complexes. Unlike the neutral N-donor ligands mentioned above, dicatechol ligands coordinate in their deprotonated form with metals and carry two negative charges for each coordination unit. As a result, triple-stranded dicatechol complexes usually bear negative charges and countercations are needed for the generation of neutral species. In contrast, counteranions are needed when neutral N-donor ligands are used. When coord socates with high diastereoselectivities. As mentioned in 1.1.2, dicatechol ligands such as 4 – 9 with alkyl chains as linker comply with the empirical odd-even rule. 6,14-20 .  One intriguing feature of the triple-stranded dicatechol complexes is that the cavity formed by the strands at the middle of either a helicate or mesocate can accommodate various cation guest(s). The ethylene-bridged helicate [Ti263]4- can encapsulate either Na+, K+or Li+.16,20 X-ray structural analysis showed one Na+ ion was captured when Na+ was used as countercation while one Li+ together with two water molecules were captured when Li+ was the countercation.  - 21 - Although the cavity was found to bind Na+ much better than Li+, experimentation at room temperature showed K+ was the most appropriate guest for [Ti263]4-.20 With an increase in linker length, the interior cavities of the complexes became larger and were thus capable of accomodating more ions (and molecules).15,19,20 The X-ray stucture of [Ti273]4- showed that the mesocate can bind one Na+ together with one water and one DMF molecule in the cavity.19 In the solid state, [Ti293]4- was found containing not one but two K+ together with two water and four DMF molecules.20 In the case of ligand 5 which possesses a short methylene linker, a very small cavity was expected for the methylene-bridged mesocate [Ti253]4-. In fact, the cavity was too small to hold even one Li+ ion. The X-ray stucture showed three lithium cations were bound on the outside instead of the interior of the mesocate.15 Even so, the countercations still played a key role for the f reparation of [Ti ormation of the discrete complex. When K+ was used for the p 253] , no defined product but rather a mixture of oligomers was obtained.  4- HO OH OH OH HO OH HO OH NH O O HN Ph Ph 72-H4 (CH2)n 73-H4 HO OH HO OH n=0    4-H4        n=1    5-H4 n=2    6-H4        n=3    7-H4 n=4    8-H4        n=6    9-H4 N N N N N N N O 63  Figure 1.21. Structures of of 4-H4 – 9-H4, 63, 72-H4 and 73-H4.  - 22 - Ligand 72 (Figure 1.21) is heterotopic and thus may lead to either HHH or HHT mesocates. The NMR spectrum of [Ti2723]4- indicated the isomers were formed in a ratio of 1:4, which is very similar to the statistical ratio of 1:3. This means there is almost no selectivity between the two coordinationunits, which is understandable because there is no great structural difference between them.75 In contrast, the benzimidazole ligand 63 has two distinct binding sites and thus can selectively form HHH co ne of the triple-stranded complexes, chiral groups were introduced in the dicatechol ligand 73. As expected, ena mplexes. To generate diastereoselectively o ntiomerically pure helicate [Ti2733]4- was formed.76 R= (CH2)4 74-H4                      75-H4                          76-H4 N R N OH OH OH OH 77-H4                            78-H4 79-H                                   80-H44 carries chiral information, an enantiomerically pure left-handed helicate [Ti2763]4- was formed. In contrast, ligand 80 which has a methylene group in the middle only generated mesocate [Ti2803]4- upon complexation with Ti4+. Figure 1.22. Structures of 74-H4 – 80-H4.  Besides alkyl chains, imine and amide groups were also employed as linkers for dicatechol ligands. Imine-bridged ligands 74 – 79 (Figure 1.22) showed high diastereoselectivity towards triple-stranded helicates.77,78 Since 76  - 23 - NH OH OH R= O R NHO OH OH (CH2)3 81-H4 82-H4 83-H4  Figure 1.23. Structures of 81-H4, 82-H4 and 83-H4. Similar to other amide-bridged ligands, dicatechol ligands such as 81 – 83 (Figure 1.23) usually lead to triple-stranded helicates.19,22,79,80 For example, although ligand 81 has an odd number of CH2 groups between the amide groups, helicate [Ga2813]6- was the only diastereomer formed in the reaction of 81 and Ga3+. n=0       84-H4 n=1       85-H4 n=2       86-H4HO OH HO OH n N N H C CH3 HO OH HO 3 OH 87-H Figure 1.24. Structures of 84-H4 – 87-H4. Dicatechol ligands with rigid linear linker have also been developed. Probably because distortion of the rigid linear linkers into a bent “C” conformation is not favoured, ligands 84 – 86 (Figure 1.24) only generated helicates.19,81,82 Ligand 87, which has a rigid Tröger’s base as linker, was also investigated for the synthesis of triple-stranded complexes. Unfortunately, similar to ligands 34 and 35, which also have Tröger’s base as linker, the chiral proligand 87 reacted with metals in a non-diastereoselective manner. 4  - 24 - NH SH SH R= O R NHO SH SH (CH2)2 NH OH OH R= O R NHO SH SH C C H2 (CH2)2 88-H4 89-H4 90-H4 91-H4 92-H4 93-H4 94-H4 95-H4  Figure 1.25. Structures of 88-H4 – 95-H4. Dicatechol derivatives 88-H4 – 95-H4 (Figure 1.25) developed in recent years contain benzenedithiol unit(s) as binding site(s) and can also generate triple-stranded helicates with selected metals.83-86 Because ligands 92 – 95 are heterotopic, they are good candidates for synthesis of directional heterometallic triple-stranded helicates. For example, when treated with Ti4+ and Mo4+, 94 produced the parallel helical anion [TiMo943]4- with Ti3+ coordinating with oxygen.85,86 These dicatechol/benzenedithiol ligands are gaining attention for construction of dicatechol supramolecular architectures.   - 25 - 1.2 Dipyrromethene and Poly(dipyrromethene) Ligands 1.2.1 Dipyrromethenes as Ligands 1.2.1.1 Dipyrromethanes and Dipyrromethenes HNNH NH NH NH α,α'-linked dipyrromethane HN 2 3 4 5 6 7 8 1  10      11   9 α,β'-linked dipyrromethane β,β'-linked dipyrromethane Figure 1.26. Representive structures of dipyrromethane isomers. Dipyrromethanes are structurally composed of two pyrrole rings linked by a methylene fragment. The recommended numbering system by IUPAC is shown in Figure 1.26. Since the 1-, 4-, 6- and 9-positions are the α positions of the pyrrole rings and the 2-, 3-, 7- and 8-positions are the β positions, dipyrromethanes can be categorized, according to the location of the methylene linker, into three groups: α,α’-linked dipyrromethanes; α,β’-linked dipyrromethanes and β,β’-linked dipyrromethanes. The 5-position is also referred to as the meso position. 4, 6-dipyrromethene N HN 1  10     11   9 2 3 4 5 6 7 8 Figure 1.27. Representive structure of dipyrromethenes. Dipyrromethenes, also called dipyrrins, are the dehydrogenated derivatives of dipyrromethanes. Figure 1.27 shows the IUPAC numbering system for 4,6-dipyrromethenes. Similar to the dipyrromethane system, the 1-, 4-, 6- and 9-positions are also referred to as the α positions, the 2-, 3-, 7- and 8-positions as the β positions and the 5-position as the meso position.   - 26 - Since the α,β’-linked and yrromethene always refe β,β’-linked isomers are relatively rare, the term dip rs to α,α’-linked 4,6-dipyrromethene. N HN NH N Scheme 1.1. Tautomerization of dipyrromethene. To achieve maximum conjugation of the π system, dipyrromethenes usually take a coplanar conformation which allows for delocalization of the π electrons. Studies show the two pyrrolic ring β-positions, or introduction of aryl groups to the meso position. α- or β-substituted dipyrromethenes are usually prepared as dipyrromethenium salts by protonation with hydrogen bromide or hydrogen chloride, while meso-substituted dipyrromethenes usually exist as the free bases. s are actually equivalent for symmetrically substituted dipyrromethenes, indicating tautomerization occurs readily by proton transfer between the two nitrogen atoms (Scheme 1.1).87 Because one of the nitrogens is sp2 hybridized and possesses a lone pair of electrons not involved in bonding, dipyrromethenes are relatively strong bases and are rather reactive towards electrophiles. In fact, the fully unsubstituted dipyrromethene is only stable below -40 oC in solution.88 However, the stability of dipyrromethenes can be dramatically increased in two ways: introduction of substituents, especially alkyl groups, to the α-or  - 27 - 1.2.1.2 Synthesis of Dipyrromethanes  NH HNN H R1 R2 R3 RCHO R1 R2 R3 R3 R2 R1 R1 = alkyl R  = H, alkyl R = H, alkyl, aryl R 2 R3 = H, alkyl acid HN NH N H R1 R2 RCHO R1 R3 R3 R1 R R3 R2 R2 R1 = alkyl R = H, alkyl, aryl Scheme 1.2. Synthesis of symmetrically substituted dipyrromethanes. a. Synthesis of α-Substituted Dipyrromethanes. Both α,α’-linked and β,β’-linked symmetrically substituted dipyrromethanes can be prepared by the condensation of the corresponding unsubstituted pyrroles with an aldehyde (Scheme 1.2). The synthesis of α,α’-linked unsymmetric dipyrromethanes on the other hand, can be achieved from substituted methylpyrroles and α-unsubstituted pyrroles (Scheme 1.3).89,90  R2 = alkyl R3 = alkyl acid NH HN N H R1 R2 R3 R1 R2 R3 R4 R5 R6 X=Br, OR CH X2 N H R4 R5 R6 + acid  Scheme 1.3. Synthesis of unsymmetric dipyrromethanes. These classic methods have advantages such as high yields and tolerate a great variety of substituents. Nonetheless, the preparation of the precursors generally requires multi-step reactions which can be time-consuming.   - 28 - N H NH HN R R N HO R H R NH HNacid + + higher oligomer NH NH R +  Scheme 1.4. Condensation of pyrrole and an aldehyde. b. Synthesis of meso-Substituted Dipyrromethanes. The most significant modern development in the synthesis of dipyrromethanes is using pyrrole as both reactant and solvent in the condensation with an aldehyde. Compared to classic methods, the value of this method lies in the fact that meso-substituted dipyrromethanes can be prepared in a single step.91,92 However, α,α’-linked dipyrromethanes, are not the only products in the one-pot condensations. α,β’-Linked dipyrromethanes, trimers and higher linear oligomers are the major side products (Scheme 1.4). In very elegant studies,93-95 Lindsey and coworkers found using excess pyrrole as both reactant and solvent m ding, the mes inimizes the formation of the side products. Employing this fin o-substituted dipyrromethanes can be prepared on a large scale by recrystallization after the removal of pyrrole by distillation. N H NH HN R acid R O N H R OH N H R=aryl NaBH4  Scheme 1.5. Stepwise synthesis of meso-substituted dipyrromethanes.  - 29 - Alternatively, meso-substituted dipyrromethanes can also be synthesized stepwise from 2-acylpyrroles as shown in Scheme 1.5. This route leads to dipyrromethanes as the only products, but the multiple steps make it less attractive.93 N H O H R NH HN R acid + NH NH R + HN NH R R=H, alkyl or aryl usually < 1% Scheme 1.6. Synthesis of β,β’-linked dipyrromethanes from pyrrole and an aldehyde. c. Synthesis of α-Free β, β’-Linked Dipyrromethanes. Presumably the ideal method of synthesizing α-free β,β’-linked dipyrromethanes is to couple two pyrrole molecules directly by a linker. However, due to the high reactivity of the α-positions over the β-positions, α,α’-linked dipyrromethanes always dominate the reaction. Although Lewis acids such as Yb(OTf)3, Sc(OTf)3 and InCl3 were reportedly able to dramatically increase the yield of α,β’-linked products to 20%,95 the production of the β,β’-linked isomers is usually negligible. It was not until 2004 that β,β’-linked dipyrromethanes were isolated by Sessler’s group96 in less than 1% yields (Scheme 1.6).  Other approaches to α-free β,β’-linked dipyrromethanes such as using N-TIPS pyrrole as substrate,97 using an alkyne as the linker precursor98 and using an open chain compound as starting material99 have also been reported. Unfortunately, all these methods have only been employed in limited cases.  - 30 - 1.2.1.3 Synthesis of Dipyrromethenes Dipyrromethenes can be synthesized from pyrrolic derivatives using various reactions. Nonetheless, the most useful and popular methods are the acid-catalyzed condensation of 2-formyl pyrroles with α-free pyrroles and the oxidation of meso-substituted dipyrromethanes prepared from the condensation of pyrrole and aldehydes. NH N N H N H R1 R2 R3 R4 R5 R6 O H + R1 R2 R3 R4 R5 R6 HBr HBr R1, R2, R3, R4, R5, R6=H, alkyl, aryl, halogen and etc. Scheme 1.7. Synthesis of substituted dipyrromethenes. a. Synthesis of α- or β-Substituted Dipyrromethenes by Condensation. Substituted 2-formylpyrroles are usually employed in the synthesis of substituted dipyrromethenes.89 As shown in Scheme 1.7, the substituents on the pyrrole rings can be hydrogen, alkyl, aryl or halogens, but the most common ones are alkyl groups. When both R1 and R6 are substituents other than hydrogen, the product is usually very stable. Therefore, the condensation can be performed at room temperature and the product can be precipitated as the dipyrromethenium salt by addition of diethyl ether. When dipyrromethenes with one α position unsubstituted are required, R1 is always set up as hydrogen because polymerization and other side reactions can be easily initiated at room temperature if R6 is hydrogen. It is no wonder that the synthesis of dipyrromethenes with both α positions unsubstituted are rather demanding. Such reactions are usually performed at low temperatures.100  - 31 - The advantages of this method include high yields (usually over 90%) and convenient work-up (no chromatography is needed to isolate the product from the reaction mixture). Once again, the multiple reactions needed for the preparation of the precursor 2-formyl pyrroles and α-free pyrroles are the disadvantages of the method. R=aryl NH N R NH HN R DDQ  Scheme 1.8. Synthesis of meso-substituted dipyrromethenes by oxidation. b. Synthesis of meso-Substituted Dipyrromethenes by the Oxidation of the Corresponding Dipyrromethanes. The presence of an aryl group at the  meso-position can dramatically improve the stability of dipyrromethenes, which provides opportunites to prepare free-base dipyrromethenes by the oxidation of the corresponding dipyrromethanes (Scheme 1.8). The most popular oxidants used for this purpose are substituted 1,4-benzoquinones such as 2,3-dichloro-5,6-dicyanobenzoquinone ( DDQ ) and p-chloranil.101,102 The oxidation reactions usually proceed smoothly at room temperature and provide excellent yields. However, chromatography is generally required to isolate the products, which limits the application of this method.   - 32 - 1.2.1.4 Coordination Chemistry of Dipyrromethenes NH N N N H  Scheme 1.9. Deprotonation of dipyrromethene. Owing to a negatively charged nitrogen and a “pyridine-like” sp2 hybridized nitrogen, deprotonated dipyrromethenes are good bidentate N-donor ligands (Scheme 1.9). Actually, dipyrromethenes are known to generate complexes with many main group and transition metal ions such as Mg2+, Ca2+, Zn2+, Ni2+, Cu2+, Hg2+, Pd2+, Rh2+, Co2+, Co3+, Fe3+, Cr3+, Mn3+, Ga3+, In3+ and Tl3+.103 Because they are monoanionic, the dipyrromethene ligands usually form neutral four-coordinate complexes with bivalent metals or uncharged six-coordinate complexes with trivalent metals. NH N NH N HCl 97-H96-H.HCl Figure 1.28. Structures of 96-H·HCl and 97-H. a. Four-Coordinate Complexes. Four-coordinate complexes are most common for dipyrromethene ligands. Either α, β-substituted or meso-substituted dipyrromethenes can coordinate tetrahedrally with metal ions. For example, both Zn962 and Zn972 have tetrahedral geometry.102,104 Even for metal ions such as Ni2+ and Cu2+, which usually generate square planar complexes, their dipyrromethene complexes also take on tetrahedral or distorted tetrahedral geometries.102 Steric repulsion between α-substituents (or even α-hydrogens if no substituents are present) of the two dipyrromethenes generally excludes the square planar conformation.  - 33 - There is only one case in which the four nitrogen atoms and the Pd2+ were found in the same plane. However, due to steric repulsion between α-substituents, the dipyrromethene units are 44o deviated from the PdN4 plane, leading to a complex with a “stepped” configuration instead of a coplanar structure.105 NH N HCl CrN 98-H.HCl   99 N OO N N Cr(OAc)2 tively unsaturated complexes will be generated. For instance, ligand 98, treated with Cr2+, produced coordinatively unsatu plexes 99 after oxidation in air (Scheme 1.10 O2  Scheme 1.10. Formation of coordinatively unsaturated octahedral complex 99. b. Six-Coordinate Complexes. Six-coordinate dipyrromethene complexes usually exhibit octahedral geometry. Because a six-coordinate octahedal center is more crowded than a four-coordinate tetrahedral center, steric hindrance usually allows only α-unsubstituted dipyrromethenes to form octahedral ML3 complexes. When α-substituted ligands are used, chances are that coordina rated octahedral com ).106 NH N NH N HCl NH N HCl 100-H.HCl                             101-H.HCl                                102-H Figure 1.29. Structures of 100-H·HCl, 101-H·HCl and 102-H.   - 34 - Ligands 100 and 101 (Figure 1.29) are the first ligands reported to generate octahedral ML3 dipyrromethene complexes.100,107 Reactions of 100 or 101 with Fe3+ or Mn3+ in the presence of aqueous ammonia produced the neutral complexes Fe1003, Mn1003 and Mn1013. Using meso-substituted dipyrromethenes, our group have synthesized a series of Co3+ and Fe3+ dipyrromethene complexes since the 1990s.108 X-ray crystallography of Co973 revealed the six nitrogens formed an almost perfect octahedral coordination sphere around the metal central. Besides transition metals, dipyrromethene ligands can also form octahedral complexes with main group metals. Ligand 102 with group 13 cations such as Ga3+ and In3+ generated lumi escent complexes Ga1023 and In1023.109 n NH HN 103                                                                        104 CN N N NC N N CNCo O 2 MeOH TEA  Scheme 1.11. Formation of octahedral complex 104. Interestingly, one singly α-substituted ligand is allowed in the DDQ Na3Co(NO2)6 formation of an octahedral dipyrromethene complex. When dipyrromethane 103 was treated with DDQ and subsequently Co3+ in situ, the unexpected complex 104 was obtained together with the expected CoL3 (Scheme 1.1). Unlike the complex Co973, 104 has one dipyrromethene whose α-position has a methoxy group instead of hydrogen.110 To date, 104 is the only known octahedral tris(dipyrromethene) complex bearing a substituent at the α-position.  - 35 - 1.2.2 Linear Poly(dipyrromethene)s as Ligands Composed of multiple dipyrromethene moieties connected by linker, poly(dipyrromethene)s are useful ligands for the formation of well-defined architectures through self-assembly.103 The most important poly(dipyrromethene)s are the bis(dipyrromethene)s. Again, based on the location of the linker, bis(dipyrromethene)s may have α,α’-linked, α,β’-linked and β,β’-linked forms (for example, the bis(dipyrromethene)s in Figure 1.30). Homotopic α,α’-linked and β,β’-linked bis(dipyrromethene) ligands are quite common whereas examples of heterotopic α,β’-linked bis(dipyrromethene)s are relatively rare. N N NH HN N N NH HN N H N NHα,α'−linked α,β'−linked β,β'−linked N 1 2 3 4 5 6 7 8 11 12 13 14 15 16 7 8 9 10 11 12 13  ntive structures of methylene-bridged bis(dipyrromethene) isomers. The IUPAC numbering system for biladiene-ac, namely, α,α’-linked methylene-bridged bis(dipyrromethene), is shown in Figure 1.30. Accordingly, β,β’-linked bis(dipyrromethene) is numbered as shown in this dissertation.  9 10 17 18 19 1 2 3 4 5 6 14 15 16 17 18 19 Figure 1.30. Represe  - 36 - 1.2.2.1 Synthesis of Bis(dipyrromethene)s  N N NH HN R R=linker NH N + a bN N NH HN R R=linker HN NH R + N H HH O O NH N  Scheme 1.12. Routes to bis(dipyrromethene)s. The synthesis of bis(dipyrromethene)s can be accessed through two routes: (a) generating dipyrromethene units first and then linking them, or (b) setting up linker first and subsequently generating dipyrromethene units through condensation (Scheme 1.12). NH N NH N BrHBr HBr SnCl4 + 107-H2.2HBr HBr HBr NBr N H N N H Br 105-H.HBr                                      106-H.HBr Scheme 1.13. Synthesis of proligand 107-H2·2HBr. An example of route (a) is the synthesis of α,α’-linked bis(dipyrromethene) 107-H2 as shown in Scheme 1.13. In the presence of tin tetrachloride, 107-H2·2HBr was prepared from α-bromomethyldipyrromethene 105-H2 and an α–unsubstituted dipyrromethene 106-H2.111 However, due to the lack of linker variety, the method is limited to methylene-bridged α,α’-linked bis(dipyrromethene)s.   - 37 - HN NHO EtO O OEt NH HN n OO EtO OEt n=0        108 n n=0        111         n=1        112 n=2        113         n=3        114 n=4 115 n=5        116 n=1        109 n=2        110 Figure 1.31. Structures of 108 – 116. In contrast, various linkers can be introduced between pyrrole derivatives. Thus route (b) is usually employed for the synthesis of either α,α’-linked or β,β’-linked bis(dipyrromethene)s. N H I EtO O N H EtO O N H EtO O H O N H EtO O 117                             118                              119 120 121  122 N H EtO O I N H EtO O OAc Cl O n-1  Figure 1.32. Structures of starting materials (117 – 122) for the synthesis of bis(dipyrromethene)s. The key intermediates of route (b) are the dipyrrolic derivatives such as 108 – 116 (Figure 1.31). Generally, directly-linked compounds such as 108 and 111 can be synthesized by Ullmann coupling of the corresponding iodopyrroles 118 and 119 (Figure 1.32).112,113 When n = 1, the most important dipyrrolic compounds are dipyrromethanes of which the synthesis has been shown in 1.2.1.2. Throu uch as 109 and 112 can gh those reactions, the dipyrromethane derivatives s  be obtained from 120 and 117 respectively.89,114 When n = 2, α,α’-linked 110 can be prepared by McMurry coupling115 from 121; β,β’-linked 113 can be synthesized from 117 and  - 38 - 122.114 When n > 2, β,β’-linked intermediates 114 – 116 with longer linkers also can be prepared from 117 and 122. N H H O HN NH N NHBr HBr HN NHO EtO O OEt HN NHO HO O OH 112                                                                  123 125 1)BnOH HBr 2)H2, Pd 126-H2.2HBr HN NH 124 Scheme 1.14. Synthesis of proligand 126-H2·2HBr. For the purpose of preparing bis(dipyrromethene)s, dipyrrolic precursors 108 – 116 need to be decarboxylated in situ or further formylated. Upon condensation with 2-formyl pyrroles or α-unsubstituted pyrroles, the formylated or decarboxylated intermediates usually produce bis(dipyrromethene)s in high yields in the form of bis(dipyrromethenium) salts.116,117 For instance, ligand 126 which has two unsubstituted α-positions was synthesized from 112 as shown in Scheme 1.14.  However, because of the challenge of the condensation of α-free dipyrrolic species with α-free pyrroles, the synthesis of α-free β,β’-linked bis(dipyrromethene)s has so far gone unreported.  - 39 - 1.2.2.2 Poly(dipyrromethene) Supramolecular Complexes  Figure 1.33. Supramolecular architectures generated from poly(dipyrromethene) ligands. Based upon the coordination chemistry of dipyrromethenes, poly(dipyrromethene) ligands have been previously reported to generate supramolecular architectures including double-stranded helicates and triangular helicates (Figure 1.33).103 Besides these supramolecules, poly(dipyrromethene) ligands may also form mononuclear complexes with metal ions. The location, length and rigidity of linker and the preferred geometry of metals usually have a great influence on the architectures of poly(dipyrromethene) complexes. HBr n=0, R1=R2=R4 3 3 2 3 2 2 r HN NH N Nn n HBr HBrHBrHBr N R1 N H R4 N H R4 N R1R2 R2R3 R3 n=0, R1=CO2Et, R2=R3=CH3, R4=H   127-H2.2HBr               n=1      126-H2.2HBr n=1, R1=R2=R3=CH3, R4=CH2CH3     128-H2.2HBr               n=2      133-H2.2HBr n=1, R1=R2=R3=R4=CH3                                                         n=3      134-H2.2 =CH , R =CH CH      130-H .2HBr               n=4      135-H .2HB 129-H2.2HBr n=1, R2=CH3, R1=R3=R4=CH2CH3     131-H2.2HBr               n=5      136-H2.2HBr n=2, R1=R2=R3=CH3, R4=CH2CH3 132-H2.2HBr n=6   137-H2.2HBr Figure 1.34. Structures of 126-H2·2HBr – 137-H2·2HBr. a. Mononuclear complexes. There are two groups of bis(dipyrromethene)s which can form mononuclear complexes. One group is α, α’-linked bis(dipyrromethene)s with short linker (n = 0 or 1). For example, mononuclear Cu127, Ni127 and Ni128 have been known since the  - 40 - 1960s.118,119 The reason that the mononuclear complexes can be formed might be that such ligands can adopt a planar conformation that Cu2+ and Ni2+ ions prefer. It is no wonder that these bis(dipyrromethene)s can also form double-stranded helicates with Co2+ or Zn2+ which prefer tetrahedral geometry. The other group of bis(dipyrromethene)s which can form mononuclear complexes is those having long flexible linkers (n>4).117 Due to the presence of the long flexible linker, one strand of ligand is able to fold itself around the same metal center with tetrahedral geometry. Bis(dipyrromethene) 137-H2, for example, reacting with Zn2+, produced mononuclear complexes predominantly. S HN NH N N RR HBr HBr R=CH3        138-H2.2HBr R=C2H5       139-H2.2HBr HN NH N N RR HBr HBr N H O R= 140-H2.2HBr  Figure 1.35. Structures of 138-H2·2HBr – 140-H2·2HBr. b. Double-Stranded Helicates. The double helix is the most common structural motif for poly(dipyrromethene) complexes. Many α,α’-linked bis(dipyrromethene)s with short linkers, even directly linked 127-H2 and 130-H2, can form double-stranded helicates upon coordination with appropriate metals.117 To avoid the formation of mononuclear complexes, metal ions which prefer tetrahedral geometry are usually used. Since β,β’-linked bis(dipyrromethene)s with short linkers (n = 1 – 4) cannot bend enough to generate mononuclear complexes, β,β’-linked bis(dipyrromethene) ligands such as 126 and 133 – 135 usually favour the formation of double helicates. But, as the length of the linker increases (n>4), double-stranded helicates become  - 41 - disfavoured. Besides C-linked ligands, S-linked bis(dipyrromethene)s 138 and 139 (Figure 1.35) were found to generate double helical complexes with Zn2+ as well.120 To induce M- or P-helicates stereoselectively, a chiral group was introduced to bis(dipyrromethene) 140-H2 (Figure 1.35).121,122 CD investigation indicated the reactions indeed proceeded with some stereoselectivity, but some diastereomers were also found. The enantiomerically pure h version around the me elicates were obtained by HPLC. No stereochemical in tal center was observed. HBr HBr HN NHN N 141-H .2HBr2 Zn(OAc)2 142 NaOAc  Scheme 1.15. Synthesis of the triangular helicate 142. c. Triangular Helicates. Rigid β,β’-linked bis(dipyrromethene)s which are not able to change their conformations to form either mononuclear complexs or double helicates have chances to form triangular helicates. For th Zn(OAc)2 generated a triangular helicate 142 with a metal/ligand ratio of 3 : 3 (Scheme 1.15).123 Recently, a similar triangular helicate but with a bigger interior cavity was synthesized using 143 (Figure 1.36) as ligand. In the solid state, a tunnel was formed by the packing of the complexes.124  instance, bis(dipyrromethene) 141-H2 wi HBr HNN 143-H2.2HBr NH N HBr  Figure 1.36. Structure of 143-H2·2HBr.  - 42 - 1.3 Research Objectives An important feature of dipyrromethene complexes is that they generally have intense absorption in the visible region due to charge-transfer or π-π* transitions.100,102,104,107-109,125 For example, the bi-ligand Zn2+ and tri-ligand Ga3+ and In3+ dipyrromethene complexes shown in Figure 1.37 have an absorption band around 500nm with a molar extinction coefficient of approximately 105 M-1cm-1.109,126 N N Ar N N ArZn MN N N N N N Ar = 2,6-dichlorophenyl, mesityl M = Ga3+, In3+ Ar Ar Ar Ar = phenyl, mesityl N N B F F BODIPY  Figure 1.37. Fluorescent dipyrromethene complexes. The optical properties of dipyrromethene complexes have been used for analytical purposes. The best examples are the boron-dipyrromethene (BODIPY) dyes (Figure 1.37), which are notable for their high fluorescence quantum yields. Due to their unique optical properties, BODIPY dyes have been employed in a variety of imaging applications, especially in biological labeling.127,128 The optical properties of the dipyrromethene complexes also make them a promising subunit for light-harvesting system. Similar to BODIPY dyes, the bi-ligand Zn2+ and tri-ligand Ga3+ and In3+ dipyrromethene complexes mentioned above not only have intense absorptions in the visible region but are also highly fluorescent. As such, dipyrromethene complexes may serve as  - 43 - accessory pigments for porphyrin-based light-harvesting arrays. In addition, because each dipyrromethene coordinate unit contains multiple dipyrromethene fragments, it can be used as a self-assembling linker for supramolecular light-harvesting antennae. To explore the optical properties of such a system, Lindsey’s group synthesized the dipyrromethene-complex-linked porphyrin triad (Figure 1.38).126,129 Their studies showed the dipyrromethene complexes can transfer energy efficiently to the porphyrins and can serve as secondary light-collection elements in porphyrin-based light-harvesting arrays. N N N N Zn N HN NH N NH N N HN Ar Ar Ar Ar Ar Ar  Figure 1.38. Dipyrromethene-complex-linked porphyrin triad. Ruthenium(II) complexes are generally stable and kinetically inert and are of considerable interest in dye-sensitized solar cells. Therefore, mixed dipyrrin/bipyridine ruthenium(II) complexes which are anticipated to be efficient dyes for light-harvesting were also reported (Figure 1.39).130 Such complexes are anticipated to be efficient dyes for the light-harvesting. Ru N N Ar N N RuN N N N Ar Ar N N N N + Figure 1.39. Ruthenium(II) dipyrromethene/bipyridine complexes.   - 44 -  Firgure 1.40. Space Filling structure of the proposed triple-stranded helicate. Coupling two or more such units through covalent bond(s) is of interest. For instance, it may improve or modify the optical properties of dipyrromethene complexes; and the interaction between metal centers may induce novel physicochemical properties.2,3 In such pursuits, supramolecular architectures formed by poly(dipyrromethene) ligands, such as double helicates and triangular helicates have been developed. However, all of the reported poly(dipyrromethene) supramolecular architectures to date are constructed on the basis of tetracoordination. No octahedral poly(dipyrromethene) supramolecular complexes have been reported even though mononuclear octahedral dipyrromethene complexes are well known. Therefore, we decided to investigate the synthesis of octahedral poly(dipyrromethene) supramolecular complexes, especially triple-stranded helicates (Firgure 1.40). The objectives for the project were to: 1) rationally design and synthesize poly(dipyrromethene) ligands suitable for octahedral coordination; 2) synthesize triple-stranded poly(dipyrromethene) complexes; and 3) explore the coordination chemistry of poly(dipyrromethene) ligands based on octahedral geometry.  - 45 -       CHAPTER TWO  RESULTS AND DISCUSSION  - 46 - 2.1 Investigations into α-Substituted Bis(dipyrromethene) Ligands 2.1.1 α,α’-Linked Substituted Bis(dipyrromethene)s As reported in Chapter 1, all previously developed bis(dipyrromethene) ligands have at least two if not all α-positions substituted. Those ligands have shown a strong tendency towards generating double-stranded helical complexes upon coordination with various metals.103 As such, methylene-bridged α,α’-linked bis(dipyrromethene)s, the most common substituted bis(dipyrromethene) proligands, were investigated initially for the synthesis of triple-stranded complexes. Ligands 158 – 161 and 165 were synthesized. Various alkyl groups were introduced to the β-positions of the ligands in order to tune properties such as solubility.   2.1.1.1 Synthesis of Proligands 158-H2·2HBr – 161-H2·2HBr The synthetic route to the α,α’-linked methylene-bridged bis(dipyrromethenium) salts 158-H2·2HBr – 161-H2·2HBr is shown in Scheme 2.1. Starting from diethyl malonate 144, ethyl pyrrole-2-carboxylate ester 117 was synthesized through a Fischer-Fink synthesis.131 A side chain was introduced through Friedel-Crafts acylation of 117 with either acetyl chloride or hexanoyl chloride. Reduction of 146 and 147 with sodium borohydride in the presence of boron trifluoride subsequently provided 148 and 149.132 To install the methylene linker, the methyl group at the 5-position of 148 and 149 needed to be converted into a good leaving group. In the case of 148, this was achieved neatly through oxidation with lead (IV) acetate at room temperature. Unfortunately, 149 could not be  - 47 - O O O O O O O O N OH NaNO2 AcOH N H O O O O Zn/AcOH R Cl O SnCl4 NH O O R O N H O O R NaBH4/BF3.OEt THF N H O O R Pb(OAc)4 AcOH O O 144                                                             145 117   75% NH HN R R HBrHBr N N H R N H R N HCl/EtOH N H 1) POCl3, DMF HBr, CH3OH NH HN R R O O O O  + NaOH, (CH2OH)2 R=C2H5      158-H2. 2HBr   91% R=C6H13     159-H2. 2HBr   93% 156 R=CH3 R=C5H11 R=C2H5 R=C6H13 R=C2H5 R=C6H13 R=C2H5 R=C6H13 R=C2H5 R=C6H13 154 (or 155) HBrHBr N N H R N H R NN H HBr, CH3OH  + R=C2H5       160-H2. 2HBr   95% R=C6H13    161-H2. 2HBr   93% 157 154 (or 155) NH HN R R O H O H R=C2H5 R=C6H13 2) Na2CO3, H2O 109  84% 151  86% 152 153 154  67% 155  65% 148   78% 149   83% 120  100% 150   84% 146  87% 147  82%  Scheme 2.1. Synthesis of proligands 158-H2·2HBr – 161-H2·2HBr.  - 48 - completely converted even with excess lead (IV) acetate, but it was found an appropriate amount of hexanes allowed unreacted 149 to be washed from the product.With 120 and 150 now in hand, the methylene-bridged dipyrrolic derivatives 109 and 151 were prepared through electrophilic substitution.89 Thermal decarboxylation133 was employed to generate the α-unsubstituted dipyrromethanes 152 and 153 which turned out to be very unstable in air. In order to minimize the deterioration of these dipyrromethanes, 152 and 153 were immediately formylated using the Vilsmeier-Haack reaction.133 In the last step, the proligands 158-H2·2HBr – 161-H2·2HBr were prepared through the hydrobromide-catalyzed condensation of 154 or 155 with pyrroles 156 or 157. The products precipitated out of the reaction mixture with the addition of diethyl ether and were collected by filtration.117   - 49 - 2.1.1.2 Synthesis of Proligand 165-H2·2HBr Unlike dipyrromethanes 152 and 153 which have to be prepared in multiple steps, dipyrromethane 162, the precursor of ligand 165, was synthesized directly from the acid-catalyzed condensation of pyrrole and formaldehyde.94 In practice, paraformaldehyde was dissolved in excess pyrrole and the solution was heated to 50 oC to break down the polymer prior to the addition of TFA. After workup and chromatography, 162 was obtained as a white solid in a 46% yield (Scheme 2.2). HBrHBr N N H N H N 165-H . 2HBr     95% N H 2 NH HN NH HN H H OO N H (CH2O)n 1) P Cl3, DMFO 2) Na2CO3, H2O H O 162   46% 163 1 55% +  162 57 164 N H +    163 HBr HBr 165-H2. 2HBr TFA  Scheme 2.2. Synthesis of proligand 165-H2·2HBr. However, attempts to synthesize proligand 165-H2·2HBr from 162 and 164 were unsuccessful. Although Mass Spectroscopy (MS) showed a peak for the target compound, a complex mixture was observed using NMR spectroscopy. The reason that the reaction did not proceed selectively might be related to the high reactivity of dipyrromethane 162. Under acidic conditions, side reactions such as polymerization and oxidation can occur with this fully unsubstituted dipyrromethane.  - 50 - To avoid side reactions, formyl groups were introduced to the α-positions of dipyrromethane 162 through a routine Vilsmeier-Haack reaction.134 The smooth condensation between diformyldipyrromethane 163 and pyrrole 157 offered 165-H2·2HBr in high yield.  - 51 - 2.1.1.3 Reactions of Ligands 158 – 161 and 165 with Trivalent Metals To favour the formation of octahedral triple-stranded complexes, trivalent metals such as Fe3+ (in the form of FeCl3) and Co3+ (in the form of [CoPy4Cl2]Cl), which were known to be able to form octahedral dipyrromethene complexes,100,108 were used to react with proligands 158-H2·2HBr – 161-H2·2HBr and 165-H2·2HBr. The metalation reactions of the ligands were carried out at reflux in a mixed solution of CHCl3 and MeOH (v : v, 1 : 1) in which both the metal ions and ligands were well dissolved. To facilitate deprotonation of the proligands, a small amount of base (NEt3 or NaOAc) was also applied. The observations and results are shown in Table 2.1. Table 2.1. Observations of the reactions of ligands 158 – 161 and 165 with Co3+ / Fe3+  Co3+ / Fe3+ Ligand Colour of the solution TLC MS 158 Changed. No nonpolar complex observed. No M2L3 complex detected. 159 Changed. No nonpolar complex observed. No M2L3 complex detected. 160 Changed. No nonpolar complex observed. No M2L3 complex detected. 161 Changed. No nonpolar complex observed. No M2L3 complex detected. 165 Changed. No nonpolar complex observed. No M2L3 complex detected.  Since the assumed M2L3 complexes are neutral and expected to be coloured, the reactions should be monitorable using thin layer chromatography (TLC). Disappointingly, no coloured  - 52 - nonpolar compounds were found by TLC and no M2L3 complex was detected by MS in any rea eaction mixtures, the peak cor esent, which excluded the possibility that the M2L3 complexes wer adation of the ligands. ction, indicating the α,α’-linked substituted bis(dipyrromethene)s do not lead to homoleptic triple-stranded complexes. According to MS analysis of these r responding to the ligand was pr e not formed because of the degr  - 53 - 2.1.2 β,β’-Linked Bis(dipyrromethene)s with α-Positions Substituted As far as the ligands are concerned, crucial factors which may affect the formation of octahedral triple-stranded bis(dipyrromethene) complexes include: 1) the location of the linker; 2) the length of the linker; and 3) the substituents, especially those at the α-positions. To examine the effect of the location and length of the linker, ethylene-bridged bis(dipyrromethene)s 174-H2 and propylene-bridged 175-H2 were investigated.   2.1.2.1 Synthesis of Proligands 174-H2·2HBr and 175-H2·2HBr The β,β’-linked dipyrrolic derivatives 166 and 167* can be prepared using methods described in 1.2.2.1. Palladium-catalyzed hydrogenolysis of 166 and 167 quantitatively provided 168 and 169 as white solids (Scheme 2.3). Upon heating in the presence of strong base, the dicarboxylic acids were decarboxylated to generate 170 and 171 from which β,β’-linked bis(formylpyrrole)s 172 and 173 were synthesized through classic Vilsmeier-Haack reaction.133 Alternatively, ethylene-bridged 172 was also prepared in one pot where 168 was decarboxylated using trifluoroacetic acid (TFA) and formylated in situ with trimethoxymethane,135 but attempts to synthesize 173 using the same method ended up with failure. Condensation of 172 or 173 with  * Both 166 and 167 used in the project were previously synthesized by colleagues.  - 54 - pyrrole 157 was quite facile. After the addition of diethyl ether, 174-H2·2HBr and 175-H2·2HBr were collected by filtration. HN NH OO O O PhPh n n=2      166    167n=3 HN NH OO HO OH n n=2        168 n=3        169 HN NH OO H H n n=2      172    68% n=3      173    54% HN NH n n=2 n=3      171     170 H2 quant. 1)TFA 2)CH(OMe)3NaOH (CH2OH)2 Pd/C NH HN HN NH N N N N HBr HBr 174-H2. 2HBr    90% 172     + H HBr HBr N 157 HBr 173     + H N 157 HBr 175-H2 2HBr   94%. 168  172    65% POCl3, DMF 2CO3, H2O 1) 2)Na or Scheme 2.3. Synthesis of proligands 174-H ·2HBr and 175-H ·2HBr.      2 2   - 55 - 2.1.2.2 Reactions of Ligands 174 and 175 with Trivalent Metals Ligands 174 and 175 were treated with Co3+ or Fe3+ while heating in the resence of triethylamine. The results (Table 2.2) were unfortunately similar to what had been observed in the case of the α,α’-linked ligands 158 – 161 and 165, p indicating no neutral triple-stranded com lexes were formed. Table 2.2. Observations of the reactions of ligands 174 and 175 with Co3+ / Fe3+.  Co3+ / Fe3+ p Ligand Colour of the solution TLC MS 174 Changed. No nonpolar complex observed. No M2L3 complex found. 175 Changed. No nonpolar c plex observed. No M2L3 complex found. om  Based on the fact that both the α,α’-linked bis(dipyrromethene) ligands 158 – 161, 165 and the β,β’-linked 174 – 175 did not generate the triple-stranded complexes, it seems that neither the length nor the location of the linker are the most crucial factors for the formation of triple-stranded complexes. Considering the dipyrromethenes that can form octahedral complexes are usually α-free (please see 1.2.1.4), it can be concluded that the size of the substituents at the α-positions must be the key factor for the generation of triple-stranded complexes.  - 56 - 2.1.3 Bis(dipyrromethene)s with Two α-Positions Unsubstituted To investigate the effect of α-substituents, α,α’-linked 179-H2·2HBr, β,β’-linked 180-H2·2HBr and 181-H2·2HBr which have two α-positions unsubstituted were synthesized and their reactions with trivalent metal ions wereinvestigated.     2.1.3.1 Synthesis of Proligands 179-H2·2HBr – 181-H2·2HBr  HNNH N HH O H O N H O H HNNH 152              154 176                177 Figure 2. 1 177. Theoretically, 179-H2·2HBr can be synthesized by 154 and 176 or 152 7 ever, to av he side reactions mentioned in 1.2.1.3, dipyrro ane 152 rmyl-3 ul e. In addition, because the preparation of 1 box s, 152 was generated from  thro boxy itu to synthesize 179-H2·2HBr (Scheme 2.4).136 Similarly, 180-H2·2HBr and 181-H2·2HBr were pre t 1. Structures of 152, 54, 176 and condensation from either and 17 (Figure 2.1). How oid t meth  and 2-fo ,4-dimethyl-pyrrole 177 co d be the superior choic 52 through thermal decar ylation is very tediou  diacid 178 ugh acid-catalyzed decar lation and used in s pared from 168 and 169, respec ively, also in excellent yields.  - 57 - HNNH HBrHBr N N H N H N 180-H2. 2HBr   84% 181-H2. 2HBr   80% NH HN HN NH N N N N HBr HBr HBr HBr 179-H2. 2HBr   81%178 NH HN HN NH OH O HO O HO O O OH HBr 177 HBr 177 168 169 O HO O OH HBr 177 Scheme 2.4. Synthesis of proligands 179-H2·2HBr – 181-H2·2HBr.   2.1.3.2 Reactions of Ligands 179 – 181 with Trivalent Metals Table 2.3. Observations of the reactions of ligands   179 – 181 with Co3+ / Fe3+.  Co3+ / Fe3+ Ligand Colour of the solution TLC MS 179 Changed. No nonpolar complex observed. No M2L3 complex detected. 180 Changed. Nonpolar complex observed. M2L3 complex detected. 181 Changed. Nonpolar complex observed. M2L3 complex detected.  Coordinating with Co3+ or Fe3+, α,α’-linked ligand 179 largely showed no difference from α-substituted ligands 158 – 161, 165, 174 and 175. No expected triple-stranded complexes were  - 58 - found (Table 2.3). However, when β,β’-linked 180 or 181 were treated with Co3+ or Fe3+, a sma are the key for the formation of triple-stranded bis(dipyrromethene) complexes. The ondly, it indicates that β,β’-linkers favour the M2 ll amount of nonpolar complexes appeared on the TLC plate. After passing through a short silica column, the pink-coloured complexes were collected. Unfortunately, the complexes were rather unstable and severe decomposition was observed during chromatography. The NMR analysis also showed the Co3+ complexes to be a complex mixture in solution. However, a species with a mass of M2L3 was detected by MS. The detection of the species was significant. Firstly, it indicates, as concluded in 2.1.2.2, that α-substituents  reason that ligands 180 and 181 can form M2L3 complexes is very likely that they have two α-positions unsubstituted, whereas the instability of these complexes is probably caused by the substituents at other α-positions of the ligands. Sec L3 complexes more than the α,α’-linkers do, which is reasonable because the linker at the α-position is equal to a substituent. Finally, the poor stability of the M2L3 complexes generated from ligands 180 and 181 implies the best chance to form stable triple-stranded complexes lies where α-free β,β’-linked bis(dipyrromethene)s are used.  - 59 - 2.1.4 Summary of α-Substituted Bis(dipyrromethene) Ligands In summary, this section has described the early work on the synthesis of triple-stranded bis(dipyrromethene) complexes. Investigations on substituted α,α’-linked bis(dipyrromethene) ligands, subst ) ligands with two α-positions unsubstituted have been carried out. Although none of these attempts was sati iple-stranded complexes, α-free β,β’-linked bis (dipyrromethene)s which have fou ituted β,β’-linked bis(dipyrromethene) ligands, and bis(dipyrromethene sfactory, the experience provided some valuable information. 1) The size of the α-substituents is crucial for the formation of octahedral triple-stranded complexes. 2) When n = 1 – 3 (n is the number of carbons in the linker), the length of a linker is very unlikely the reason which inhibits the generation of triple-stranded complexes although it will definitely affect the structure of such a complex. 3) The location of the linker is also important. α,α’-Linked bis(dipyrromethene)s, even α-unsubstituted ones, cannot form triple-stranded complexes. In order to increase the chance of generating stable tr r α-positions unsubstituted were deemed to be synthesized.  - 60 - 2.2 Synthesis of α-Free β,β’-Linked Bis(dipyrromethene) Ligands 2.2.1 Retrosynthesis HN N R2 R3 R1 NH N R3 R1 R2 R1, R2, R3 = H or alkyl n = 1, 2, 3 n HN R3 NH R3 n H O H O HN R3 NH R3 n + N R3 NH R2 + R1 HN R3 NH R3 n H O H O N H R3 H O or(I) (II) (III) (IV) (VI)  Scheme 2.5. Retrosynthesis of α-free β,β’-linked bis(dipyrromethene)s.  As shown in Scheme 2.5, α-free β,β’-linked bis(dipyrromethene)s (I) might, in principle, be accessed from three precursors: α-free dipyrromethenes (II), α-free β,β’-linked bispyrroles (III) or α-unsubstituted β,β’-linked bis(formylpyrrole)s (IV). However, α-free dipyrromethenes (II) are not suitable substrates because the installation of a β,β’-linker between two α-free dipyrromethene units is not pragmatic. Nor are α-free β,β’-linked bispyrroles (III) because, even if these species were available, poor regioselectivity of the condensation with formylpyrroles can be anticipated because of the presence of four reactive α-positions. Therefore, using α-unsubstituted β,β’-linked bis(formylpyrrole)s (IV) as precursors is probably the only promising route. (V)  - 61 - Still, several challenges can be anticipated for following this route. First of all, the stability of the proposed α-free bis(dipyrromethene)s may be very poor under acidic conditions. Secondly, it is challenging to control the acid-catalyzed condensation. Side reactions such as polymerization, scrambling and oxidation may readily occur under the acidic conditions because both of the reactants (α-unsubstituted β,β’-linked bis(formylpyrrole)s and α-free pyrroles) possess unsubstituted α- β,β’-linked bis(  positions. Moreover, the key precursors, α-unsubstituted formylpyrrole)s were also unknown. Theoretically these compounds might be synthesized from either substituted β,β’-linked bis(formylpyrrole)s (V) or α-unsubstituted 2-formylpyrroles (VI). The advantage of using substituted β,β’-linked bis(formylpyrrole)s as starting materials is their straightforward synthesis, but removal of the α-substituents can be demanding. On the other hand, if α-unsubstituted 2-formylpyrroles are employed as precursors, a method needs to be developed to direct the linker to the β-position.  - 62 - 2.2.2 Attempts to Synthesize α-Unsubstituted β,β’-Linked Bis(formylpyrrole)s from Substituted Precursors N H R2 R3 R1 OR O R = H or alkyl R2, R3 = alkyl N H R2 R3 R1∆NH R2 R3 R1 SO2Cl2 ROH NaOH  Scheme 2.6. Demethylation of pyrroles through decarboxylation. The α-methyl group of pyrroles can be facilely transformed into a carboxyl or ester group using SO2Cl2 (Scheme 2.6).133 Such a reaction provides a useful way to remove the methyl group from a pyrrole ring through thermal decarboxylation. In a similar manner, the α-methyl groups of substituted β,β’-linked bis(formylpyrrole)s may also be removed. With substituted bis(formylpyrrole)s 172 and 173 in hand, preparation of α-unsubstituted bis(formylpyrrole)s 186 and 187 by decarboxylation was commenced. HN NH n H O H O HN NH n CNO O NC O O n=2            172 n=3            173 n=2     182    69%n=3     183    83% O O CN HN NH HOOC COOH NC O O CN O O n HN NH n H O H O n=2            184 n=3            185 n=2            186 n=3            187 decarboxylation 1)SO2Cl2 2)H2O H N  Scheme 2.7. Proposed synthesis of α-unsubstituted bis(formylpyrrole)s 186 and 187 from 172 and 173.  - 63 - As shown in Scheme 2.7, to protect the aldehyde groups, bis(formylpyrrole)s 172 and 173 were treated with methyl cyanoacetate and converted into 182 and 183 in the presence of base. Un m 172 and 173. ince synthesizing α-unsubstituted bis(formylpyrrole)s from such α-substituted species is so ing α-substituted species as starting materials was eventually aba fortunately, when 182 or 183 were reacted with excess sulfuryl chloride, a complex mixture was obtained. Oxidation with lead(IV) acetate or potassium permanganate was also unsuccessful. Consequently, the expected 186 and 187 could not be prepared fro S formidable, the idea of us ndoned.  - 64 - 2.2.3 Synthesis of α-Unsubstituted β,β’-Linked Diformyldipyrromethanes from α-Unsubstituted Pyrrole Derivatives As discussed in 1.2.2.1, a methylene linker is the easiest linker to introduce. For this reason, the synthesis of β,β’-linked methylene-bridged bis(formylpyrrole)s, namely, β,β’-linked diformyldipy iformyldipyrromethanes is the regioselectivity. It is well known in pyrrole chemistry that the α-positions are usually much more reactive than the β-positions towards an electrophile. To direct a linker to the β-position in the presence of unsubstituted α-position(s), the reactivity of the unsubstituted α-position(s) of a suitable substrate must be suppressed. rromethanes, was focused on in the following study.  2.2.3.1 Substrate Selection The challenge of using α-unsubstituted pyrrole derivatives as substrates to synthesize β,β’-linked d N H O R Br2 N HO R R=H, alkyl, aryl Br N HO R Br Br+ N H N H Br NBS  Scheme 2.8. Bromination of pyrrole and α-carbonylpyrroles. An approach to suppressing the reactivity of the unsubstituted α-position(s) is to introduce an electron-withdrawing group (EWG) to the ring. For example, the carbony  group of α-carbonylpyrroles can direct bromine at the β-position when treated with Br l 2 at low temperature (Scheme 2.8). In contrast, a similar bromination reaction applied to pyrrole provides  - 65 - α-brominated compounds as the major products. However, such EWGs are usually not able to completely deactivate the α-position. The formation of α,β-dibrominated compound in the former reaction indicates the α-position is still susceptible to electrophiles. N H CO Et2 NH NHNH HN + CHO NO2 NO2 NO2 TiCl4 189 190 EtO2C CO2Et EtO2C CO2Et 188 65% 2%  Scheme 2.9. Condensation of pyrrole ester 188 with 2-nitrobenzaldehyde. Unfortunately, such reactivity of the unsubstituted α-position(s), although reduced, is still problematic during the process of setting up a linker. As shown in Scheme 2.9, when pyrrole ester 188 was used as substrate, α,α’-linked bispyrrole 189 was reported as the predominant product.137 N H H O N NC H O O NC O O N H191 192   82% ∆, N H NC O O 192 NH HN H HNC O O CN O O 193 33% CH2(OMe)2 BF3, -10 NH HN H H163 O O NC O O NEt3 oC 193       25%  Scheme 2.10. Condensation of pyrrole 192 with dimethoxymethane.  - 66 - This reaction indicates that a very strong EWG is required in order to direct a linker to the β-position. Moreover, for the purpose of synthesizing α-unsubstituted β,β’-linked diformyldipyrromethanes, the EWG also should be convertible into an alehyde group. Based on these requirements, the commercially available 2-formyl pyrrole 191 may serve as the starting material. The advantages include: 1) various EWG groups can be introduced to protect the formyl group and thus the reactivity of the α-position can be tuned; and 2) the formyl group can be regenerated after a linker has been installed. Pyrrole 192 was the substrate first investigated. Using a reported procedure,138 pyrrole 192 was prepared by treating 191 with methyl cyanoacetate and diethylamine (Scheme 2.10). At -10 oC, 192 was treated with dimethoxymethane under acidic conditions and a bright yellow compound 193 was produced as the major product. Unfortunately, comparison with an authentic compound revealed that 193 was the α,α’-linked isomer. N H NC CN N H H O NC CN N H191 194   87% N H CN NC 194 CH2(OMe)2 BF3 a mixture  Scheme 2.11. Condensation of pyrrole 194 with dimethoxymethane. When pyrrole 194, which possesses a stronger electron-withdrawing substituent, was used instead of 192, the condensation reaction led to a complex mixture of products (Scheme 2.11). Although the mixture was not separated and identified, it is clear that such an  - 67 - electron-withdrawing substituent is not strong enough to direct a linker exclusively to the β-position. Br N H N ClO4 NIS 57%, only product NaHCO3 N H Br2 O H I N H N ClO4 NH O H 90% 195                                          196 Scheme 2.12. Halogenation of 195. 1-(Pyrrol-2-ylmethylene) pyrrolidinium perchlorate 195, an iminium salt of 2-formylpyrrole 191, attracted our attention during the exploration for suitable substrates. The important feature of 195 is its positively-charged α-group which exhibited an exclusive meta-directing effect in aromatic halogenation reactions.139,140 For instance, treating 195 with bromin  generated β-brominated 196 in excellent yield and iodination of 195 with N-iodosuccinimide (NIS) produced β-iodinated 197 as the only product (Scheme 2.12). Due to these excellent results, the pyrrolidinium salt 195 was selected as the substrate for the synthesis of α-unsubstituted β,β’-linked diformyldipyrromethanes. NaHCO3 195                                         197 e  - 68 - 2.2.3.2 Synthesis of β,β’-Linked Diformyldipyrromethane 201 N H N ClO4 195 BF3 2)NaHCO3 1)CH2(OMe)2 A new species with a mass of 202 N H N 198                              199                                                195 ClO4 N H O H N H2 ClO4NH HClO 191  Scheme 2.13. Condensation of 195 with dimethoxymethane.* As shown in Scheme 2.13, the substrate 195 was quantitatively prepared from 191 and pyrrolidinium perchlorate 199 according to a reported procedure.139 Following a modified condensation of pyrrole and an aldehyde, the pyrrolidinium perchlorate 195 was treated with dimethoxymethane and boron trifluoride at room temperature. After stirring for 10h, the reaction mixture was hydrolyzed with aqueous NaHCO3. A new species was obtained as a white solid after column chromatography. 4 100% HN NH H H O O 201 NH NH H H O O 200 NH HN H H O O 163 Figure 2.2. Structures of diformyldipyrromethane isomers: 163, 200 and 201. Mass spectroscopy showed this compound had a mass of 202, indicating it is one of the three isomers: α,α’-linked 163, α,β’-linked 200 or β,β’-linked diformyldipyrromethane 201 (Figure  * Perchlorates are known as oxidizers and are explosive. Although we found that 195 was safe under the reaction conditions, extra safety precautions are necessary.  - 69 -  Figure 2.3. 1H NMR spectra of 201(a) and 163(b) in d -DMSO. 2.2). Meanwhile, the 1H NMR  it had a highly symmetric stru yrromethane 201 was gen 6 spectrum of the compound suggested cture. Only two broad singlets (7.04 and 6.82 ppm) appeared in the aromatic region, which excluded the α,β’-linked structure. As shown in Figure 2.3, both the chemical shifts and coupling pattern of the compound exhibit characteristics which are distinct from the authentic α,α’-linked 163. Unlike the split peaks of 163, the two peaks of 201 in the aromatic region are broad singlets, indicating they are weakly coupled and thus not neighbouring hydrogens. Based on this information, it can be concluded that β,β’-linked diformyldip erated from the reaction.  Figure 2.4. ORTEP structure of 201.  - 70 - To confirm its structure, a single crystal was grown by vapour diffusion of hexane into a THF solution of the pure 201. The β,β’-linked structure was confirmed by X-ray diffraction analysis (Figure 2.4). In the solid state, the planes of the two pyrrolic rings are at an angle of 99.6 degrees. Due to intramolecular N-H…O hydrogen bonds, the oxygens of the α-aldehyde groups face the nitrogens of the same pyrrole ring. N H N ClO4 NH 195 N ClO4 OH N H N O N H N H N OH H 202 N OH O  Scheme 2.14. Proposed formation mechanism of 202. The reaction can be carried out in methylene chloride, chloroform or acetonitrile, but solubility was better in acetonitrile, which was deemed the preferred solvent. Acetone, however, is to be avoided for the reaction. In contact with acetone, a quantitative conversion of 195 to a new species 202 was observed. Similar to a reaction reported by Johnson and his colleagues141 using dipyrromethenes, 202 was formed probably by an insertion of acetone to 195 (Scheme 2.14). The structure of 202 was also confirmed by NMR spectroscopy and X-ray diffraction analysis (Figure 2.5).  - 71 -  Figure 2.5. ORTEP structure of 202. To optimize the formation of β,β’-linked diformyldipyrromethane 201, various acids were surveyed as catalysts. It was found that Brønsted acids such as trifluoroacetic acid, methanesulfonic acid, p-toluenesulfonic acid and sulfuric acid were not able to catalyze the formation of 201. Lewis acids including tin(IV) chloride, titanium(IV) chloride, indium(III) chloride and ytterbium(III) triflate cannot replace BF3·OEt2, either. Aluminum chloride did catalyze the reaction, to produce 201, but in a much lower yield (<2%). The reaction temperature also had a great influence on the reaction. Increasing the reaction temperature from 25 to 80 oC led to an increase in the yield of β,β’-linked product. Unfortunately, undesired side-products (very likely α,α’-linked 163 or α,β’-linked 200) were also observed when the temperature was higher than 65 oC. Therefore, 60 oC was used as the optimal reaction temperature. Attempts to increase the yield using microwave irradiation were unfortunately unsuccessful. Under the optimized conditions for the reaction, 201 was obtained in a 30% yield and over 60% of 2-formyl pyrrole 191 was available for recovery. Although the yield is not excellent, it is clear that the β,β’-linked 201 was the only diformyldipyrromethane isomer produced in the reaction.  - 72 - 2.2.3.3 Synthesis of meso-Substituted β,β’-Linked Diformyldipyrromethanes The successful synthesis of β,β’-linked diformyldipyrromethane 201 provided a useful way to synthesize a series of β,β’-linked diformyldipyrromethanes. Various aldehydes were applied to t 5. The results are shown in T he acid-catalyzed condensation with the pyrrolidinium perchlorate 19 able 2.4. Table 2.4. Condensation results of 195 with an aldehyde. N H N HN NH 4 R ClO H O H O O H R entry                R            T(oC)    time(h)   product   yield(%) 1 F F F FF OMe 2 3 25         10           -               0 60         10          204           4 60         10          205           7 60    10          203           9 4 5  60         10          206          < 1 F F F FF 6 25         10           -               0 Me Me Me 1)BF3 2)NaHCO3 + 195  Surprisingly, expected products were not generated from either benzaldehyde or pentafluorobenzaldehyde at room temperature. When the reaction temperature was increased to 60 oC, the desired meso-substituted β,β’-linked diformyldipyrromethanes were ultimately generated but in very low yields.  - 73 - What caused such low yields? A comparison between the reaction using aromatic aldehydes with the former one using dimethoxymethane as reagent revealed only one difference---that dimethoxymethane is an acetal. Very likely, it is the difference in reactivity between an aldehyde and an acetal that caused the big difference in the yields. R = 4-nitrophenyl                209 O O R OHClO  on silica, ∆H R R = pentafluorophenyl        207     R = 4-methylphenyl        210 R = 2,4,6-trimethylphenyl   208     R = 2,6-dichlorophenyl  211 4 CH(OMe)3  Scheme 2.15. Synthesis of acetals 207 – 211. Perchloric acid on silica has been reported as an efficient catalyst for the conversion of aldehydes to acetals.142 Using this catalyst, the acetals were prepared from the correponding ald d in acetonitrile while a good yield was achieved in chl ehydes (Scheme 2.15) and applied to the condensation reaction. The results are shown in Table 2.5.  Several interesting phenomena were observed in the experiments: (1) Ketals were unreactive with 195 under the same conditions; (2) The formation of 206 was sluggish and the yield was low probably due to steric hindrance (entry 4 in Table 2.5); and (3) Preparation of 216 should not be performed in acetonitrile. For some unknown reason, the expected product was not obtaine oroform (entry 9 in Table 2.5).   - 74 - Table 2.5. Condensation results of 195 with an acetal. N H N HN NH ClO4 R H O H O 1)BF3 2)NaHCO3 + O R 195 O entry                               T(oC)   time(h)   product   yield(%) 1 F F F FF OMe 2 3 60         10          204        41 60         10          205        38 60         10          203        46 4 60         48          206        17 5 Cl 60         10          212         68NO2 6 60         10          213         55CO2Me 7 60         10          214         39 Me Me 8 60         10          215         35Me 10 60         10          217         25Me 11 60         10          201         30H Me 9* 60         10          216         35 Cl Cl R *Acetonitrile was used as solvent except for entry 9 where chloroform was used.  Based on these observations and the data on Table 2.4 and Table 2.5, it can be concluded the relative reactivities of acetals towards 195 followed the general sequence: aromatic acetals > aliphatic acetals >> aldehydes > ketals. In addition, aromatic acetals with electron-withdrawing group(s) seem relatively more productive than those with electron-donating group(s).  - 75 - What is curious about the reactions is that acetals are much more productive than the corresponding aldehydes. The mechanism of Lewis-acid-promoted nucleophilic substitution reactions of acetals has been intensively studied and can be either SN1 or SN2 depending on reaction conditions and substrates.143,144 However, no comparison between the reactivity of an acetal and that of the corresponding aldehyde has been made except in one report. Assuming the nucleophilic substitution reaction of an acetal has the SN1 mechanism, Mayr and Gorath145 investigated the reaction rate constants of carboxonium ions of acetals. It was found the acetal carboxonium ions are 103 – 106 times more reactive than the corresponding aldehyde-boron complexes. Since the reaction of 195 with an acetal was observed faster in acetonitrile than in chloroform and the acetal showed much higher reactivity than the corresponding aldehyde, the reaction might have he carboxonium ion o-substituted β,β’-linked difo occurred via an SN1 mechanism, but attempts to capture t s failed.  The relatively low yields are the biggest disadvantage of the method developed here. As shown in Table 2.5, most of the yields of the mes rmyldipyrromethanes produced by this method are in the range of 30 - 50%, with the highest one less than 70%. The reason may lie in the strong electron-withdrawing character of the iminium group of the substrate 195. However, it is this same character that accounts for the high regioselectivity observed. Although the purpose of reducing the reactivity of the α-position has been fulfilled, the reactivity of the β-position seems being reduced as well. There might be room  - 76 - to increase the yields by using substrates with higher reactivity or by introducing a highly reactive reagent to replace the acetals. Nevertheless, this method is the only one known to date to selectively form the α-unsubstituted β,β’-linked diformyldipyrromethanes, which are also promising precursors of many new species, for example, N-confused porphyrins.146-148 Compared with the low yield and formidable multi-step synthesis of such species from substituted starting materials, this method represents a rather useful and efficient route to the α-unsubstituted diformyldipyrromethanes.  - 77 - 2.2.4 Synthesis of α-Free β,β’-Linked Bis(dipyrromethene) Proligand 220-H2·2HBr HN NH N NHBr HBr + 201 HN NHO O H H HBr -50o N H H O N N O Cl N O Ph NH2NH2 NaOH 219 218 33% ∆ 220-H2. 2HBr 94% Scheme 2.16. Synthes microwave is of α-free proligand 220-H2·2HBr. The procedure for the synthesis of α-free bis(dipyrromethene) ligand 220 is shown in Scheme 2.16. The α- reported.149 As a benefit, the method avoids the ted ating, the α-free pyrrole 219 was eactions, low temperature (- 50 oC) was applied. Even so, if methanol or e free pyrrole 219 was synthesized from butyraldehyde as ious distillation of 219. Upon he  released from 218 quantitatively in the presence of strong base. As discussed in 2.2.1, side reactions and the instability of the product are the major challenges for the condensation of β,β’-linked diformyldipyrromethane 201 and 3,4-diethyl pyrrole 219. When the reaction was performed at r.t., it only resulted in an insoluble black solid. In order to reduce the side r thanol were used as solvent, side reactions would still take over. To shorten the time during which the product may react further in solution, tetrahydrofuran (THF) was employed as the  - 78 - reaction solvent so that 220-H2·2HBr precipitated out in situ. After all the substrate was consumed, diethyl ether was then added to induce more precipitation. Once dried, the solid form of 220-H2·2HBr was found to be quite stable and can be safely stored for months. However, 220-H2·2HBr in solution is very unstable and loses its quality in less than 15 min. at room temperature.  - 79 - 2.3 Synthesis of Triple-Stranded Helicates and Mesocates Using Ligand 220 2.3.1 Synthesis of Co3+ and Fe3+ Triple-Stranded Complexes The short life span of ligand 220 in solution is a big challenge for effective complexation with metals. To save time for the metalation, it required 220-H2·2HBr to be dissolved quickly before the metalation could be carried out. Because dissolving the dry solid of 220-H2·2HBr is time-consuming, freshly synthesized and filtered 220-H2·2HBr is preferred for the metalation. The reaction temperature is also crucial for the metalation process. Although heating increases the rate of degradation of the proligand, heating was found to be necessary, as it was for the synthesis of mononuclear octahedral dipyrromethene complexes. It was also found that the complexation was efficient around 60-70 oC. Thus, a refluxing solution of CHCl3/CH3OH (1 : 1, v : v) was used as the reaction medium. HN NH N NHBr BrH A   +   B M3+ ∆ NEt3 M=Co, A=221    26% M=Co, B=222    16%220-H2 . 2HBr M=Fe,  A=223    13% M=Fe,  B=224      9% Scheme 2.17. Synthesis of Co3+ and Fe3+ triple-stranded bis(dipyrromethene) complexes In practice, a solution of CHCl3 and CH3OH was heated to reflux in advance and both reactants dissolved in CHCl3/CH3OH were then added quickly (Scheme 2.17). The solution immediately became red, indicating certain reaction had already occurred between the metal and ligand. Upon the addition of a small amount of base, the colour darkened and nonpolar complexes were produced.  - 80 - After the removal of solvents, the reaction residue was chromatographed on a short silica column using CH2Cl2 as the eluant. Interestingly, the nonpolar product separated into two bands on a TLC plate when less polar eluants were used. Further chromatography using a one-meter long column ultimately afforded the isolation of two products ( A-type and B-type ) in an approximate ratio of 3 : 2, with the A-type complexes being the major products in both cases of Co3+ and Fe3+ complexes. The two types of complexes displayed very similar properties such as solubility and polarity. Nevertheless, the B-type complex was slightly more polar, which enabled the separation from A-type complex.  MALDI-TOF mass spectroscopy indicated that A-type and B-type complexes had the same mass corresponding to M2L3. Therefore, both helicate and mesocate should have been generated in the same reaction. In the case of the diamagnetic Co3+ complexes, the 1H NMR spectrum of A-type 221 showed a singlet for the CH2 linker at 3.51 ppm while B-type 222 exhibited two doublets for the CH2 linker at 3.25 and 3.36 ppm (Figures 2.6 and 2.7). Given the methylene hydrogens of the linker would be homotopic in a D3 helicate, but diastereotopic in a C2h mesocate, complexes 221 and 222 are the helicate and mesocate, respectively. The 1H NMR of the paramagnetic Fe3+ complexes were also detected but over a much wider range (-30 to +30 ppm). Although the peak multiplicity was not observed and the peaks could not be assigned with certainty, 224 exhibited two small peaks at 9.53 and 5.36 ppm instead of one normal peak, indicating 224 is a mesocate and 223 is a helicate.  - 81 -  Figure 2.6. 1H ect o2L t 2 H   NMR sp rum of C 3 (221) in CD2Cl2 a 5 oC (300 M z).  Figure 2.7. 1H NMR spectrum of Co2L3 (222) in CD2Cl2 at 25 oC (300 MHz).  - 82 -  Figure 2.8. ORTEP structures of triple-stranded complexes: Co2L3 helicate 221 (a) (P -1, R1=0.065*), Co2L3 mesocate 222 (b) (P 63/m, R1=0.033), Fe2L3 helicate 223 (c) (P -1, R1=0.055), and Fe2L3 mesocate 224 (d) (P 63/m, R1=0.038). The helicates were a racemic mixture. * Refined on F, I>2σ(I). For publication, the R1 values of the small molecules are requied to be less than 0.100.  - 83 - Table 2.6. Selected bond lengths, bond angles and metal distances of 221 and 223. Bond length (Å) 221 223 Bond angle ( o ) 221 223 N(1)-M(1) 1.939(4) 1.984(2) N(1)-M(1)-N(2) 93.05(15) 92.31(9) N(5)-M(1) 1.939(4) 1.961(2) N(5)-M(1)-N(6) 93.43(15) 91.80(9) N(9)-M(1) 1.939(4) 1.974(2) N(9)-M(1)-N(10) 93.56(16) 92.43(9) N(2)-M(1) 1.927(4) 1.969(2) N(1)-M(1)-N(9) 89.45(15) 8.41(10) N(6)-M(1) 1.934(4) 1.965(2) N(1)-M(1)-N(10) 87.12(15) 87.79(8) N(10)-M(1) 1.932(4) 1.964(2) N(2)-M(1)-N(10) 90.47(15) 88.79(8) N(3)-M(2) 1.934(4) 1.961(2) N(3)-M(2)-N(4) 92.91(15) 92.14(8) N(7)-M(2) 1.935(3) 1.958(2) N(7)-M(2)-N(8) 93.52(15) 91.99(8) N(11)-M(2) 1.945(4) 1.972(2) N(11)-M(2)-N(12) 93.17(16) 92.25(8) N(4)-M(2) 1.951(4) 1.969(2) N(3)-M(2)-N(11) 90.80(15) 89.08(8) N(8)-M(2) 1.934(4) 1.90(2) N(3)-M(2)-N(12) 86.53(15) 87.45(8) N(12)-M(2 89.61(8) ) 1.932(4) 1.972(2) N(4)-M(2)-N(12) 90.98(15) Mean bond length 1.937 1.968 Distance of metals 7.817 7.965 angle of the linker 114.4 115.2 C-C-C bond  Table 2.7. Selected bond lengths, bond angles and metal distances of 222 and 224. Bond length (Å) 222 224 Bond angle (  ) 222 224 o N(1)-M(1) 1.9481(10) 1.9707(12) N(1)-M(1)-N(2) 93.22(4) 92.14(5) N(2)-M(1) 1.9471(9) 1.9696(11) N(1)-M(1)-N(1’) 89.30(4) 89.66(5) N(1)-M(1)-N(2’’) 87.85(4) 88.22(5) Mean bond length 1.948 1.970 N(2)-M(1)-N(2’) 89.75(4) 90.05(5) Distance of metals 8.138 8.140 C-C-C bond angle of the linker 112.6 112.4   - 84 - The structures of the helicates and mesocates were further confirmed by X-ray crystallographic analysis (Figures 2.8). In the solid state of the four complexes, each trivalent metal is octahedrally coordinated to three dipyrromethene segments which are roughly perpendicular to each other. The mean N-Co bond length is 1.937 Å for 221 and 1.948 Å for 222 (Table 2.6), very close to the mean N-Co (1.945 Å) of a previously reported mononuclear octahedral dipyrromethene Co3+ complex.108 The mean N-Fe bond length of 223 is 1.968 Å and that of 224 is 1.970 Å (Table 2.7), also very similar to a reported monomeric complex (1.967 Å).125 The twist angle, the angle of rotation between the two metal centers, is 101° for helicate 221 and 98° for helicate 223, causing a 27.9 Å and 29.3 Å helical pitch, respectively. Due to the diff  and 2.7). However, the distances between the two metal centers of the helicates are interestingly shorter than those of the mesocates in both cases (7.817 Å vs. 8.138 Å for Co3+ complexes; 7.965 Å vs. 8.140 Å for Fe3+ complexes).  Nevertheless, as far as each coordination unit is concerned, a Λ or ∆ unit of the helicates resembles to a great extent the corresponding unit of the mesocates and they can be almost perfectly superimposed upon each other. The structural resemblance of a helicate and mesocate pair explains the similarities in their solubility and polarity. erent wrapping of the strands, the linker C-C-C bond angles of helicates are 1.8° and 2.8° greater than those of the mesocates Co2L3 and Fe2L3, respectively (Table 2.6  - 85 - For the same reasons, the optical absorptions of a pair of helicate and mesocate in solution were also very omplexes* were not able to be determined because of the presence of hexanes, it is clear that the four complexes have intense chromophores (ε > 40,000 M-1cm-1). As shown in Figure 2.9, the primary spectral feature of the Co3+ or Fe3+ helicate resembles very much that of the Co3+ or Fe3+ mesocate. The Co3+ helicate 221 and mesocate 222 have absorbance maxima at 507 and 504nm, while the Fe3+ helicate 223 and mesocate 224 have broad absorbance with maxima at 483 and 480nm. Compared to the mesocates 222 and 224, the helicates 221 and 223 are slightly bathochromically shifted and have a small shoulder between 550 and 570 nm.  similar. Although the accurate molar extinction coefficients of the c  Figure 2.9. Optical absorption spectra of 221 – 224 in chloroform. The intense band of complexes 221 – 224 around 500nm is mainly attributed to ligand-to-metal charge transfer (LMCT). However, the contribution of π-π* transitions of the  *These complexes were contaminated with hexanes during chromatograghy. Attempts to remove the contaminants failed.  - 86 - liga  the Co3+ complexes 221 or 222. Although ligand 220 is unstable because of the high reactivity of the unsubstituted α-positions, both the helicates and mesocates have high stability. With heating at 150 oC overnight, decomposition was not observed. Several factors may contribute to the stability. Firstly, the coordination with metal ions reduces the electron density on the dipyrromethene unit and thus decrease the reactivity of the α-positions. Secondly and more importantly, the steric arrangement of the coordination units can protect the α-positions. According to the X-ray structure analysis (Figure 2.7), the α-positions on each strand of either helicates or mesocates are shielded by the dipyrromethene units of the other strands. It is noteworthy that, in the case of 221 and 222, the well-known inertness of octahedral Co3+ complexes may also contribute to the stability of the complexes. Intriguingly, under the same conditions (heating at 150 oC overnight), isomerizision of either the isolated bis(dipyrromethene) helicates or mesocates was not observed. nd should not be excluded because they also fall in the same region. The pattern of the band at 483 or 480nm of complexes 223 or 224 is analogous to the reported mononuclear complex Fe1003,100 but the binuclear 223 and 224 are distinguished by lower transition energy and the major band has a prounced bathochomic shift. A similar phenomenon was also observed in the cases of  - 87 - 2.3.2 Synthesis of Triple-Stranded Complexes with Other Trivalent Metals Table 2.8. Complexation of 220 with Co3+, Fe3+, Mn3+, Ga3+ and In3+. ++ 3            Mn             225*           1340         ---                   36 4            Ga             226*           1370        3 : 2# HN NH N NHBr BrH . 220-H2 2HBr M L2 3 M3+ ∆ NEt3 1            Co          221, 222        1342        3 : 2#               42 2            Fe          223, 224        1348        3 : 2              22                38 5             In              227*           60        3 : 2#               32 entry         M           products        MS         A : B     yield(%, in total) 14 *   The complexes are a mixture of helicate and mesocate. #   The ratios were determined using NMR spectroscopy. ++ The ratio was determined by the yields of the isolated complexes. Besides Co3+ or Fe3+, ligand 220 is also able to form neutral nonpolar complexes with trivalent metals such as Mn3+, Ga3+ and In3+. The results are shown in Table 2.8. MS analysis showed all the nonpolar complexes had a mass of M2L3. In the cases of Ga3+ and In3+, NMR analysis was consistent with the fact that the complexes were a mixture of triple-stranded helicates and mesocates. It showed the helicate/mesocate ratios were also roughly 3 : 2, indicating the product ratio of the self-assembly process is likely independent of the particular metal. Unlike the Co3+ or Fe3+ helicates and mesocates, the Mn3+, Ga3+ and In3+ complexes are silica sensitive. Severe decomposition was observed when TLC was performed on silica gel. Although the nonpolar complexes were isolated from the reaction mixture on alumina, the diastereomers unfortunately had very similar Rf values and could not be separated.   - 88 - In summary, the novel α-free ligand 220 has been proven capable of generating neutral lent metals. The yields, however, are rela triple-stranded helicates and mesocates with various triva tively low. This is probably related to the poor stability of ligand 220 in solution which not only causes a competition between complexation and degradation but also limits the reaction time.  - 89 - 2.4 Attempts to Synthesize a β,β’-Linked α-Fluorobis(dipyrromethene) Ligand The successful synthesis of complexes 221-227 has proved that the size of α-substituents is indeed crucial for the synthesis of trip e-stranded bis(dipyrromethene) complexes. As shown earlier in this chapter, bis(dipyrromethene)s with α-substituents which are as big as a methyl group cannot lead to stable triple-stranded complexes. Unfortunately, the α-free ligand 220 is very unstab l le in solution. To improve ligand stability and explore the maximum size of α-substituents which allows the formation of stable triple-stranded complexes, fluorine was considered as a substituent at the α-position. As shown in Scheme 2.18, efforts have been made to synthesize the fluorine-substituted proligand 234-H2·2HBr. HN NH N NHBr BrH H N O O N H CCl3 O O N H O O N H F O O SO2Cl2 H2O NFSI HN NHO H O H F F N H F NaOH 228 N O 229 231  63% 232  50% 233 HO OH O 230 78% in 2 steps ZrCl4 201 234-H2. 2HBr Scheme 2.18. Attempted synthesis of α-fluorobis(dipyrromethene) ligand 234. Starting from pyrrole ester 228, the α-methyl group was removed using heat-promoted decarboxylation after conversion to a carboxyl group. Treating 231 with N-fluorobenzenesulfonimide (NFSI) provided α-fluoropyrrole ester 232 as white solid. In the  - 90 - presence of a strong base, 232 was further decarboxylated and the product was extracted with hexanes. However, upon evaporation under reduced pressure, a very fast unknown reaction occurred and led to the formation of a black, insoluble material. Alternatively, the product of the decarboxylation of 232 was used for the condensation without removing the hexanes. Unfortunately, the reaction also resulted in a complex insoluble mixture and the expected proligand was not obtained.  - 91 - 2.5 Synthesis of Triple-Stranded Complexes using Bis(meso-aryldipyrromethene) Ligands 2.5.1 Synthesis of β,β’-Linked Diacyldipyrromethanes The biggest disadvan ce the introduction of a tage of the α-free ligand 220 is its poor stability. Sin lkyl substituents to α-positons impeded the formation of stable triple-stranded complexes, the only promising way to improve the stability of α-free bis(dipyrromethene) ligands may be to introduce an aryl group to each dipyrromethene unit. As such, β,β’-linked bis(meso-aryldipyrromethene) ligands were designed. N H Ar O HN NH Ar Ar O OHN NHN N Ar Ar  Scheme 2.19. Retrosynthesis of bis(meso-aryldipyrromethene) ligands. As shown in Scheme 2.19, β,β’-linked diacyldipyrromethanes are the key precursors of the bis(meso-aryldipyrromethene)s. The new species were synthesized using a strategy similar to the synthesis of diformyldipyrromethane 201. The substrates, acylpyrroles, can generally be prepared on a large scale from pyrrole through Friedel-Crafts reactions.150 However, acylpyrroles, unlike 2-formylpyrrole, cannot be converted to the pyrrolidinium perchlorates due, likely, to steric hindrance. Fortunately, the ketone group is not as reactive as an aldehyde group and the acylpyrroles could be used to react with dimethoxymethane without protecting the ketone group. N H Ph O HN NH Ph Ph O O 238 12% NH NH Ph Ph O O 237 20% NH HN Ph Ph O O 236 4% + + 235 CH2(OMe)2 BF3 Scheme 2.20. Synthesis of dipyldipyrromethanes.  - 92 - Due to the differences in substrate, distinct phenomena were observed in the synthesis of diacyldipyr  in the con ed very rap ven at room temperature. Unfortunately, the high reactivity was also problematic and side Thirdly, the reaction was greatly affected by the choice of solvent. At the same temperature, the reaction went much faster in CH3CN than in CH2Cl2 and less side products were generated in CH3CN, which was thus selected as reaction solvent. In addition, the electronic features of the aryl group also had a great influence on the reactivity of the acylpyrrole substrates. A strong electron-withdrawing aryl group tended to favour the formation of the β,β’-linked isomer and also allowed the reaction to proceed romethanes. Firstly, all the three diacyldipyrromethane isomers were produced densation of acylpyrroles with dimethoxymethane. Benzoylpyrrole, for example, produced the α,α’-linked 236, α,β’-linked 237 and β,β’-linked 238 with a product ratio of 1 : 5 : 3 (Scheme 2.20). In contrast, only β,β’-linked 201 was generated when 1-(pyrrol-2-ylmethylene) pyrrolidinium perchlorate 195 was used as substrate. Evidently, the acyl groups cannot efficiently suppress the reactivity of the α-position. Consequently, poor regioselectivity was obtained. For the same reason, acylpyrroles showed higher reactivity than the pyrrolidinium salt 195. For instance, the condensation of benzoylpyrrole 235 and dimethoxymethane proceed idly e  reactions were found to dominate the reaction system. Therefore, both reaction temperature and reaction time must be restricted to certain ranges to achieve the highest yields of the desirable β,β’-linked products.  - 93 - controllably at room temperature (r.t.). Table 2.9 shows the results under optimized conditions. The three i  somers were separated on silica columns. Table 2.9. Reaction conditions and yields for the synthesis of diacyldipyrromethanes. N H Ar entry         Ar          Solvent      T(oC)   time(min)            products (yield%) 1 Cl Cl 2 3 0          60        236(4%)     237(20%)  238(12%) 25         40        240(2%)     241(12%)  242(11%) 4 0         120       243(3%)     244(13%)  245(10%) F F F FF 25         20            *                *             239(18%) Me Me Me BF3O CH2(OMe)2 α,α'-linked  α,β'-linked  β,β'-linked HN NH Ar O Ar O CH3CN CH3CN CH3CN CH3CN * Pure compound was not obtained.   - 94 - 2.5.2 Synthesis of β,β’-Linked Bis(meso-aryldipyrromethene) 250-H2 HN NHO Ar O Ar HN NHHO Ar OH ArNaBH4 Ar=phenyl                     238 Ar=phenyl                     246  100 100% Ar=pentafl henyl   239 % uorop Ar=pentafluorophenyl   247  100% Scheme 2.21. Reduction of diacyldipyrromethanes. Since the ketone groups are not as reactive as aldehyde groups, diacyldipyrromethanes cannot condense with pyrrole directly. Yet the reduced diacyldipyrromethanes, the diols, are rather reactive towards nucleophiles. When treated with excess NaBH4, diacyldipyrromethanes 238 and 239 were converted quantitatively to diols 246 and 247 (Scheme 2.21). Surprisingly, β,β’-linked diacyldipyrromethanes 242 and 245 were not convertible to the corresponding diols under similar conditions. Even performing the reduction with heating could not bring about the conversion. Although a stronger reducing agent such as LiAlH4 was able to reduce the carbonyl group, a complex mixture was produced. Such an observation is quite unusual because a smooth reduction of the α,α’-linked diacyldipyrromethanes by NaBH4 is well-known.151  HN NH NH HNHN NH HO Ar OH Ar Ar Ar Ar=phenyl                     246 Ar=pentafluorophenyl 247 Ar=phenyl                     248   82% Ar=pentafluorophenyl   249   80% N H  Scheme 2.22. Synthesis of β,β’-linked bis(meso-aryldipyrromethane)s. To increase the efficiency of the subsequent condensation, pyrrole was employed as both reactant and solvent (Scheme 2.22). Due to the susceptibility of the methylene linker, scrambling occurred in the acid-catalyzed condensation, leading to the formation of a small amount of  - 95 - meso-aryldipyrromethanes. Nevertheless, using column chromatography, β,β’-linked bis(meso-aryldipyrromethane) 248 and 249 could be isolated as viscous tan-coloured liquids. HN NH N N Ph Ph DDQ 250-H2 45% HN NH NH HN Ph Ph 248  Scheme 2.23. Oxidation of β,β’-linked bis(meso-phenyldipyrromethane) 248. The oxidation of tetrapyrroles is very complicated.87 The oxidants may attack at least four different positions (1-, 5-, 9- and 10-positions) and produce a variety of products. Fortunately, when treated with 2 equivalents of DDQ, 248 was smoothly converted to the desired bis(meso-phenyldipyrromethene) 250-H2 at room temperature (Scheme 2.23). The milder oxidant chloranil, however, seemed only able to convert one of the dipyrromethane units. Surprisingly, neither DDQ nor chloranil could convert 249 to desirable product efficiently. Increasing the reaction time or temperature only resulted in the formation of scrambled product, meso-pentafluorobenzyldipyrromethene. The oxidation of 249 was not pursued further.  With a phenyl group at the meso-position of each dipyrromethene unit, the free base bis(meso-phenyldipyrromethene) 250-H2 exhibited good stability in organic solvents and retained its constitution for hours at reflux in MeOH/CHCl3 solution.  - 96 - 2.5.3 Synthesis of Triple-Stranded Complexes using Ligand 250 Table 2.10. Complexation of ligand 250 with Fe3+, Co3+, Mn3+, Ga3+ and In3+. M2L3 M3+ ∆ NEt3 1               Fe               251*           1462         ---           31% 2               Co              252*           1469       3 : 1#         9% 3               Mn              253*           1461        ---            74% 4               Ga              254*           1491       2 : 1#        71% 5                In               255*           1581       2 : 1        34% HN NH N N Ph Ph # entry            M          products           MS        A : B    total yield 250-H2 * The complexes are a mixture of helicate and mesocate. # The ratios are determined using NMR spectroscopy. Similar to ligand 220, ligand 250, upon heating, can produce neutral M2L3 complexes with Fe3+, Co3+, Mn3+, Ga3+ and In3+ (Table 2.10). To drive the reaction to the product side, it was performed in methanol and ligand 250 was added after being dissolved in a small amount of chloroform. As such, the nonpolar M2L3 complexes were precipitated out of solution during the reaction. Because the ligand is stable, heating can be prolonged for hours to ensure the reaction goes to completion. The complexation of ligand 250 with M3+ was evidenced by NMR spectroscopy. Upon coordination, the broad N-H signal disappeared around 12-13ppm. In addition, the two pyrrol protons which gave signals at 7.69 and 7.38 ppm in the proligand had a pronounced upfield shift in the complexes, indicating the protons were shielded by the neighboring dipyrromethene  - 97 - segments of other strands. The presence of two sets of signals indicated that both helicate and mesocate . The helicate/mesocate ratio is roughly 2 : 1, which is close to that of M22203 complexes. Compared to ligand 220, the yields of Mn3+ and Ga3+ triple-stranded complexes have been imp were generated from the same ligand as in the case of ligand 220 roved dramatically using the bis(meso-phenyldipyrromethene) ligand 250. The yield of Fe2L3 complexes, although increased, is still relatively low. This might be caused by the competition between the complexation and the precipitation of Fe3+ in the presence of base. Surprisingly, when [Co(py)4Cl2]Cl, which worked well with ligand 220, was used, the expected complexes were generated in very low yields.  - 98 - 2.5.4 Synthesis of Quaternary-Carbon-Bridged Bis(meso-aryldipyrromethene) 260-H2 With the presence of an aryl group at the meso-position of each unit, the stabilities of bis(dipyrromethene) ligands were substantially improved. However, problems were met upon the oxidation of the bis(meso-aryldipyrromethane)s. To improve the efficiency of oxidation, the two dipyrromethane units might be isolated by introducing a quaternary-carbon linker. N H Ph O HN NH Ph Ph O O NH NH Ph Ph O O C(CH3)2(OMe)2 BF3, +   256  20%   257  22%234 Scheme 2.24. Synthesis of quaternary-carbon-bridged diacyldipyrromethanes. The synthesis of the key precursor, the β,β’-linked quaternary-carbon-bridged diacyldipyrromethane 257 resembles that of the methylene-bridged 238. However, because the reactivity of ketals is much lower than that of acetals, heating is necessary for the synthesis of 257 (Scheme 2.24). The yield of t ∆ he desired product 257 was found to be highest after heating one hour at 80 oC and longer reaction time did not lead to higher yield. An interesting aspect of the reaction is that the α,α’-linked isomer was not generated significantly. In contrast, when the same substrate was used in the synthesis of 238, α,α’-linked isomer 236 was also produced. The facts indicate that not only the substrate can affect the product ratio, but the linker can as well.  Following the synthesis of bis(meso-phenyldipyrromethene) 250-H2, the quaternary-carbon-bridged diacyldipyrromethane 257 was reduced with NaBH4 and condensed with pyrrole, which resulted in an efficient formation of 259. As anticipated, the  - 99 - quaternary-carbon-bridged bis(meso-phenyldipyrromethane) 259 could be converted smoothly to bis(meso-phenyl-dipyrromethene) 260-H2 by DDQ, but a minor amount of the scrambled product 5-phenyldipyrromethene was also formed. Nevertheless, the use of chloranil suppressed scrambling considerably. After chromatography, the free base bis(meso-phenyldipyrromethene) 260-H2 was harvested as a red solid with a yield close to 90%. HN NHO Ph O Ph HN NHHO Ph OH PhNaBH4 HN NH NH HN Ph Ph HN NH N N Ph Ph DDQ pyrrole BF3 257 258 259 83% 260-H2 87% 100%  Scheme 2.25. Synthesis of quaternary-carbon-bridged proligand 260-H2.   - 100 - 2.5.5 Synthesis of Triple-Stranded Complexes using Ligand 260 Table 2.11. Complexation o3+, Mn3+, Ga3+ and In3+.  of ligand 260 with Fe3+, C M2L3 M  NEt3 1            Fe                261            1547         ---            52 2            C 2    14 3            M 263      -- 4            Ga               264            1575        8 : 1         70 5             In 5        8 : 3+ ∆ o                26          1553      : 1        28 n                         1545    -             58                 26          1665   1         29 HN NH N N Ph Ph entry         M       major product*     MS        A : B#   yield(%) 260-H2 jor pro  helicate. #  The ratios are determined using NMR spectoscopy.  Table 2.11 shows the complexation results of ligand 260 with Fe , Co3+, Mn3+, Ga  and In3+ under the sam  of ligand 250. Sim  ligand 260 produced triple-stranded complexes with Fe3+, Mn3+ and Ga3+ in higher yields than ligand 220 did. However, expected Co2 3 4 2 iple 2 3 3 2 6 2 3 * The ma duct is a 3+ 3+ e conditions used in the metalation ilar to 250, ligand L  complexes were not generated when [Co(py) Cl ]Cl was used as the metal source. Nevertheless, tr -stranded Co L  complexes can be synthesized with Na [Co(NO ) ] but in relatively low yields. The low yields are likely caused by the poor solubility of the reagent in general solvents. As expected, two sets of 1H NMR signals were observed for the nonpolar M 260  (M=Co, Ga and In) complexes, indicating both helicates and mesocates had been generated. It is noteworthy, however, that ligand 260 led to a predominant formation of one of the complexes. In  - 101 - contrast, ligands 220 and 250 yielded both helicate and mesocate in close yields. Interestingly, the helicate/mesocate (A : B) ratio was largely determined by the ligands while the effect of metal ions was very small. Due to the paramagnetism of Fe22603 and Mn22603 complexes, the exact helicate/mesocate ratio was not able to be detected by NMR in the cases. However, recrystallization enabled the separation of the predominant diastereomer from the mixture in all the cases except the In2L3 complexes.  Crystals suitable for X-ray analysis were grown by vapour diffusion. X-ray crystal structure analysis of the pr d each metal was octahedrally coordinated to three di egments of the three ligand strands (Fi edominant diastereomers showed they all had a helical structure an pyrromethene s gure 2.10). In the solid state, the helicates Fe22603 (261) and Co22603 (262) have quite similar M-N bond lengths and comparable N-M-N bond angles to the helicates Co22203 (221) and Fe22203 (223). The mean M-N bond length is 1.969 Å for the helicate Fe22603 and 1.935 Å for the helicate Co22603 (Table 2.12). However, the twist angles of the quaternary-carbon-linked bis(dipyrromethene) helicates are obviously greater than those of the methylene-bridged helicates M22203 (M= Fe, Co). The differences are 6o and 4o for Fe3+ and Co3+ helicates, respectively. The M-M distance is 7.630 Å for the helicate Fe22603 and 7.576 Å for the helicate Co22603. In both cases, the M-M distance is shorter than that of the cooresponding methylene-bridged helicates. Consequently, the helical pitch is 26.4 for the helicate Fe22603 and 25.9 Å for the helicate Co22603.  - 102 -  Figure 2.10. ORTEP structures of helicates 261 (a) (C 2/c, R1=0.046*), 262 (b) (C 2/c, R1=0.043), 263 (c) (C 2/c, R1=0.064) and 264 (d) (C 2/c, R1=0.042). Phenyl groups and hydrogen atoms are omitted for clarity. The helicates were a racemic mixture. * Refined on F, I>2σ(I). For publication, the R1 values of the small molecules are requied to be less than 0.100.  - 103 - Table 2.12. Selected bond lengths, bond angles and distances of metals  of helicates 261 – 264. Bond length (Å) Helicate 261 Helicate 262 Helicate 263 Helicate 264 N(1)-M(1) 1.9688(19) 1.9263(17) 2.000(4) 2.0373(19) N(2)-M(1) 1.9802(19) 1.9350(18) 2.227(4) 2.0641(19) N(3)-M(1) 1.9728(19) 1.9497(17) 2.019(4) 2.0564(19) N(4)-M(1) 1.9589(19) 1.9458(17) 2.017(4) 2.0445(19) N(5)-M(1) 1.978(2) 1.9356(18) 2.235(4) 2.0554(19) N(6)-M(1) 1.9528(19) 1.9201(17) 2.005(4) 2.0478(19) Mean bond length (Å) 1.969 1.935 2.084 2.051 Distance of metals (Å) 7.630 7.567 7.700 7.715 C-C-C bond angle (o) 1 9 109 109 109 0 Twist angle(o) 103.705 104.918 98.473 101.350  Similarly, each coordinate unit of the helicate Ga22603 (264) also closely resembles the reported mononuclear complexes109. The Ga-N bond length of 2.051 Å compares well the reported bond lengths of 2.054 and 2.053 Å (Table 2.12). The twist angle is 101o and the dist ific h e the mean length of the ance between the Ga3+ ions is 7.715 Å, leading to a helical pitch of 27.5 Å. Compared to the ideal octahedral coordination of the helicates Fe22603, Co22603 and Ga22603 at each metal center, a sign ant tetragonal elongation was observed in the helicate Mn22603 (263). The mean length of two elongated Mn-N bonds is 2.231 Å w il  - 104 - other four Mn-N bonds is 2.010 Å (Table 2.12). The axial elongation indicates the Mn3+ is in a high-spin state, which is also in agreement with the reported ground state of a mononuclear complex.107 Similar elongation was also reported for porphyrin Mn(III) complexes,152 tetraazacyclotetradecane Mn(III) complexes153 and a bis(N-(2-picolyl)picolinamido) Mn(III) complex154. The twist angle of the Mn3+ helicate is 98o and the distance between the ions is 7.700 Å, resulting in a helical pitch of 28.3 Å. To the best of our knowledge, this is the first X-ray structure of a manganese(III) dipyrromethene complex.  Figure 2.11. Optical absorption spectra of the helicates 261 – 264 in chloroform. Similar to the triple-stranded complexes 221 – 224, the primary UV-Vis spectral feature of the helicates 261 – 264 is an intense absorption band with maxima at around 500nm (Figure 2.11). Compared to the corresponding mononuclear analogues, the major band of the dinuclear triple-stranded complexes has a pronounced bathochomic shift of approximate 40 nm and greater molar extinction coefficients. 100,108,109 The optical properties of the metal complexes are usually  - 105 - strongly dependent on th  bis(dipyrromethene) com e central metal. This is also the case for these plexes. The absorption spectra of the transition metal complexes are characterized as broad band with relatively weak absorbance while the major band of Ga3+ helicate is sharp and more intense. The strong resemblance between the helicates M22603 and M22203 (M = Fe, Co) indicates the substituent effect of ligand on the optical properties of the triple-stranded complexes isvery small.   - 106 - 2.5.6 Formation of Helicate versus Mesocate One significant finding of this study is that a triple-stranded bis(dipyrromethene) helicate/mesocate pair can be separated and do not interconvert. In the case of complexes 221 – 224, the helicates and mesocates were separated by chromatography. When ligand 260 was used, the helicates 261 – 265 were also obtained through recrystallization since the complexes were the predominant products. Even when heated at 150 °C overnight, isomerization was not observed for any of the isolated complexes. In the case of complexes 225 – 227 and 251 – 255, the helicate and mesocate were not separated primarily because they had very similar Rf value on alumina and they were not stable on silica gel. However, the ratio of helicate versus mesocate can be monitored using NMR spectroscopy and thus the interconversion, if there is any, should be detectable. The variable temperature NMR (VT NMR) of In3+ complexes 227 and 255 are shown in Figure 2.12 and 2.13. The proton signal of 227 was detected in the range of -61 – 70 °C, while 255 was investigated from r.t. to 155 °C. Since the characteristic linker CH2 hydrogens on each strand are in different chemical environment for helicates and mesocates, these peaks can be identified and used to determine the helicate/mesocate ratio. In both cases, once again, the change of temperature did not change the ratio. In contrast, as mentioned in 1.1.2, Raymond’s group found that both mononuclear and dinuclear catechol complexes readily isomerized in solution through a nondissociative intramolecular Bailar twist.22,155 They also observed both the bishydroxypyridinone helicate and mesocate complexes were in thermodynamic equilibrium in solution.23  - 107 -  Figure 2.12. VT 1H NMR of In3+ complexes 227 in d-chloroform.  Figure 2.13. VT 1H NMR of In3+ complexes 255 in d4-1,2-dichlorobenzene.  - 108 -  Figure 2.14. Top views of the Λ configuration (a), Bailar twist intermediate (b) and ∆ configuration (c) for the reported hydroxypyridinone coordination unit.*  Figure 2.15. Top views of the postulated Ray-Dutt twist intermediate (a), ∆ configuration (b) and postulated Bailar twist intermediate (c) of the dipyrromethene coordinationunit.* The α hydrogens have been coloured fo  r clarity. ion pathway through ligand  What makes the phenomena so different? We believe that steric hindrance plays a key role here. As shown in Figure 2.14, the hydroxypyridinone coordination unit, having an open unhindered structure, can readily achieve the D3h intermediate required of a Bailar twist (b in Figure 2.14) without breaking any ligand-M bond. However, in the case of the bis(dipyrromethene) complexes, both nondissociative intermediates resulting from either a Bailar twist or Ray-Dutt twist represent serious steric conflict between the α-hydrogens and are thus unfavoured (Figure 2.15). Moreover, an alternative interconvers  * The structures were drawn based on the crystallographic data of the corresponding complexes.  - 109 - dissociation is also not favoured, since breaking at least two strong Met-N bonds would be required and Thompson's group156 has shown, using chiral M2L2 complexes, that such dissociative processes do not readily occur. As a result, interconversion between a triple-stranded bis(dipyrromethene) helicate and the diastereomeric mesocate was not observed and both thermodynamic and kinetic products were trapped in the reaction. It is noteworthy, however, that octahedral Co3+ complexes are known for their kinetic inertness. In the case of Co3+ bis(dipyrromethene) helicates and mesocates, the inertness supports the lack of interconversion. Nevertheless, steric hindrance must be the major contributor because interconversion was not observed in the case of other metal complexes. N N N N N N N N C conformer S conformer  Scheme 2.26. The interconversion between “C” and “S” conformation of bis(dipyrromethene) ligand. Obtaining both helicates and mesocates in this study shows that even ligands with a single methylene spacer can take an either “C” or “S” conformation through bond rotation (Scheme 2.26). Consequently, it raises a general question: what really determines the formation of a helicate versus mesocate? Based on this study and reported works, there are two distinct scenarios (Scheme 2.27). If a helicate/mesocate pair is able to interconvert under the reaction  - 110 - conditions, chances are that the thermodynamic product will be generated, or the helicate/mesocate will be in thermodynamic equilibrium as suggested by Raymond ((a) in Scheme 2.27). In the cases that the pair is not interconvertible under the reaction conditions, the reaction can be either kinetically-controlled or thermodynamically-controlled ((b) in Scheme 2.27). In bord  which is exa erline cases, both kinetic and thermodynamic products can be produced, ctly what was observed in this study. S conformer C conformer Helicate Mesocate S conformer C conformer Helicate Mesocate (a) (b) Scheme 2.27. Formation of helicate versus mesocate. As discussed by Albrecht,19,77,157 the length of a linker is one of the most important features of a ligand and has a great influence on ligand conformation. Therefore, it also has a great influence on the product ratio. However, the odd-even rule has apparent flaws. Firstly, a mesocate formed by ligand with a linker having an odd number of atoms is not necessarily more thermodynamically-favoured than the corresponding helicate and vice versa. It can be quite the opposite when a different type of ligand is involved. On the other hand, the odd-even rule cannot explain the cases in which both a helicate and mesocate were formed. Therefore, the length of the linker cannot be relied for predicting the formation of helicate versus mesocate although it is important and can be related to the favoured product in many cases. It is clear that no single factor can simply determine the formation of helicate versus mesocate.  - 111 - 2.6 Summary and Conclusion In this study, a series of α,α’-linked and β,β’-linked bis(dipyrromethene) ligands including α-substituted ligands 158-161, 165, 174-175, ligands 179-181 with two α-position unsubstituted, and α-free ligands 220, 250 and 260 were designed, synthesized and examined as candidate ligands for the synthesis of triple-stranded bis(dipyrromethene) complexes. It was found that the size of α-substituents was the key factor for the formation of the neutral M2L3 complexes. Only the α-free bis(dipyrromethene) ligands are able to generate stable triple-stranded bis(dipyrromethene) complexes. In order to synthesize the α-free ligand 220, a novel method for the synthesis of unknown β,β’-linked α-unsubstituted diformyldipyrromethane was developed. It was found that the strong electron-withdrawing pyrrolidinium group can direct the linker exclusively to the β-position and using an acetal as a prolinker can improve the yield dramatically. Using the novel α-free bis(dipyrromethene) 220 as proligand, triple-stranded helicates and mesocates were synthesized with various trivalent metals including either transition trivalent metals Mn3+, Fe3+ and Co3+ or main group metals Ga3+ and In3+. Several pairs of helicates and mesocates were isolated for the first time. Because of steric hindrance, the ∆ dipyrromethene unit cannot convert to the Λ configuration through either Bailar or Ray-Dutt twists. Therefore, both kinetic and thermodynamic products were trapped. The formation of both helicate and mesocate in the same reaction overturned the earlier proposed odd-even rule. To improve the stability of α-free bis(dipyrromethene)s, bis(meso-phenyldipyrromethene)s 250 and 260 were also designed and synthesized. These ligands generate triple-stranded  - 112 - complexes with trivalent Fe3+, Co3+, Mn3+, Ga3+ and In3+. As hoped, the yields of M2L3 complexes were improved significantly in most cases. Interestingly, the quaternary-carbon-bridged ligand 260 yields helicates with much higher stereoselectivity than ligands 220 and 250.  All the triple-stranded bis(dipyrromethene) complexes are strong chromophores. They usually have absorbance maxima around 500nm with molar extinction coefficients over 105 M-1cm-1. Compared with mononuclear tridipyrrinato complexes, the triple-stranded complexes are apparently bathochromically-shifted. Due to their interesting optical properties, these complexes can be, in principle, widely modified and may find promising applications.  In short, triple-stranded bis(dipyrromethene) helicates and mesocates which have strong chromophores have been successfully synthesized using the novel α-free ligands developed in this study. The synthesis and isolation of a pair of helicate and mesocate from a single reaction have provided a long missing piece in this area and gives us a better understanding of the formation of helicates versus mesocates through self-assembly.   - 113 - 2.7 Future Perspectives metal ligand Figure 2.16. Representive structures of polyhedral supramolecule cages. The host-guest chemistry of polyhedral supramolecule cages has been of great interest in recent years because of various promising applications.80,158 It was reported that an iron (Fe2+) based tetrahedral cage can keep hig  from burning and can also release the substance under certain condition.159 Such studies have provided a useful model for storing and releasing dangerous subst ecules serving as drugs.  hly flammable white phosphorus ances or reactive small mol spacer N N NH HN spacer  =                                  etc. N H R O I R R  Scheme 2.28 Synthetic route to proposed ligands. As anionic ligands, poly(dipyrromethene)s are good candidates for the synthesis of neutral polyhedral complexes such as tetrahedral and cubic complexes (Figure 2.16). With an octahedral or distorted octahedral geometry, each dipyrromethene coordination unit automatically constructs one vertex of a polyhedron and each strand of ligand becomes one side. Based on the experience gained in working with triple-stranded helicates and mesocates, the ligands used for octahedral coordination ought to have unsubstituted α-positions. In practice,  - 114 - rigid α-free β,β’-linked bis(dipyrromethene)s might be employed to avoid the formation of triple-stranded helical complexes. Bis(dipyrromethene)s with a rigid linker instead of a flexible one can be synthesized as proposed in Scheme 2.28. The dipyrrolic precursors of the novel ligand can be synthesized through coupling reactions of β-iodoacylpyrrole with a pro-linker. Similar reactions have been done in our group.124 To tune the solubility of the ligands, either alkyl or polar substituents can be placed at the β-positions or on the spacer. We anticipate some cage complexes will be generated from these ligands.  N NH N HN N HN N HN N N N N N N N N N NH HN N N HN H N N known doubly                                     triply                                      fully N-confused porphyrins (NCPs) are a family of normal porphyrin isomers (Figure 2.17). Due to their structural differentiation, NCPs show unique properties different from the normal porphyrins.  Since NCPs have outward-pointing nitrogens, they were able to form intriguing supramolecular complexes; doubly NCPs were also found able to stabilize the rare high oxidation states of various metals; NCPs usually possess several stable tautomers and some unknown porphyrin                                 singly                                   doubly                                            N-confused                           N-confused N-confused                            N-confused                           N-confused Figure 2.17. Representive structures of porphyrin and N-confused porphyrins. 146-148,160-162 tautomeric forms exhibit strong anion-binding properties.  - 115 - However, due to the limited availability of precursors, out of 95 isomers,148 only a few types of NCPs have been reported. In this study, the synthesis of novel β,β’-linked diformyldipyrromethanes, α,β’-linked and β,β’-linked diacyldipyrromethanes has been developed. Such species are natively precursors to a large number of NCPs and make the synthesis of novel doubly, triply and even fully confused NCPs attainable. Such studies are undergoing in our group. We look forward to the genesis of new members of the porphyrin family in the near future.  - 116 -       CHAPTER THREE:  EXPERIMENTAL  - 117 - 3.1 General Materials and Instrumentation All reagents and solvents were purchased from Aldrich, Fisher and other commercial suppliers and used without further purification. Analytical thin-layer chromatography (TLC) was performed using commercial pre-coated alumina or silica gel plates which contain a fluorescent RMS) were taken on ratos MS50 (EI), or Kratos Concept IIHQ (EI), or Bruker Esquire~LC (ESI) spectrometers.  the m eter. 1H NMR, 19F NMR and 13C NMR spectra were recorded using a Bruker 300 spectrometers and chemical shifts are reported in ppm using the residual non-deuterated solvent as reference standard (CDCl3: 1H 7.27ppm, 13C 77.00ppm; CD2Cl2: 1H 5.32ppm, 13C 54.00ppm; d -acetone: 1H 2.05ppm, 13C 29.92ppm; CD CN: 1H 1.94ppm, 13C 1.39ppm; d -DMSO: 1H 2.50ppm, 13C 39.51) at 25 oC. To distinguish the carbon type, the APT experiment was performed using a indicator. Column chromatography was carried out using silica gel (particle size: 0.040-0.063 mm, 230-400 mesh) or alumina (neutral; 6% H2O added for brockman activity III; particle size: 60-325 mesh). The regular mass spectra (MS) and high-resolution mass spectra (H K The mass of etal complexes was examined using MALDI-TOF in the presence of 2-[(2E)-3-(4-tert-butylphenyl)-2-methylprop-2-enylidene]malononitrile (DCTB) as matrix on the Bruker Biflex IV instrument. Elemental analysis was performed on a Carlo Erba Elemental Analyzer EA 1108. The melting points of crystalline compounds were measured in the range of 0 to 230 oC with a Bristoline melting point apparatus and are uncorrected. The UV-vis spectra were measured on a Varian Cary 5000 spectrophotom 6 3 6  - 118 - spin-echo-echo sequence in all the cases (τ = 1/J). The 1H1H COSY NMR spectra were recorded on a Bruker 400 spectrometer (F1 and F2 = 400 MHz) at 25 oC. X-ray crystallographic analyses* were carried out on a Bruker X8 APEX diffractometer with r     graphite monochromated Mo-K radiation. Data were collected and integrated using the Bruke SAINT software package. The structures were solved by direct methods.163 All refinements were performed using the SHELXTL crystallographic software package of Bruker-AXS.       * All the crystal structures were solved by Dr. Brian O. Patrick from the department.  - 119 - 3.2 Experimental Procedure and Data 5,5'-methylenebis(4-hexyl-3-methyl-1H-pyrrole-2-carbaldehyde) (155) HNNH H O H O C5H11 C5H11  To a solution of ethylene glycol (20mL) were added 151 (1.5g, 3.1mmol) and aqueous NaOH (2g in 2mL H2O). After the reaction mixture was heated at 180 oC for 16h under N2, it was y id (65%). Tan crystals (mp: 184-185 oC). Rf (silica; ethyl acetate/CH2Cl2, 1 : 2 ) 0.47. 1H NMR (300 MHz, d6-DMSO) δ = 11.50 (br s, 2H, NH), 9.47 (s, 2H, CHO), 3.85 (s, 2H, meso-CH2), 2.26-2.20 (t, J = 7.3 Hz, 4H, CH2), 2.15 (s, 6H, CH3), 1.25-1.10 (m, 12H, CH2), 1.03 (br, 4H, CH2), 0.85-0.79 (t, J = 7.3 Hz, 6H, CH3). 13C NMR (75 MHz, d6-DMSO) δ = 176.3, 134.5, 127.8, 122.4, 31.2, 30.1, 28.8, 23.4, 22.8, 22.1, 13.9, 8.5. HRMS (EI, M+) Calcd for C25H38N2O2: 398.29333. Found: 398.29430. cooled to r.t. to allow 153 to precipitate out of solution. The pink solid was then collected b filtration, washed with H2O and dried under reduced pressure. Dry 153 was immediately dissolved in anhydrous N,N-dimethylformamide (DMF) (7.5mL) and cooled to -10 oC under N2. Subsequently, POCl3 (2.1mL) was added dropwise to the solution. After stirring at the same temperature for 30min, the solution was warmed to and heated at 80 oC for another 1h before it was cooled to r.t. To work up, the solution was treated with methanol (30 mL) and excess Na2CO3 in H2O. After filtration, 155 (0.8g, 2mmol) was obtained as a tan sol  - 120 - bis(5-((3,5-dimethyl-2H-pyrrol-2-ylidene)methyl)-3-ethyl-4-methyl-1H-pyrrol-2- yl)methane dihydrobromide (158-H2·2HBr) N H N NN HHBr HBr Dialdehyde 154 (0.286g, 1mmol) was dissolved in CH Cl  (20mL). To this solution was added pyrrole 156 (0.2g, 2.1mmol) followed by the addition of HBr (1mL, 33% in acetic acid). After stirring for 1h at r.t., diethyl ether (100mL) was added and 158-H ·2HBr precipitated as a red solid. Filtration provided 158-H ·2HBr (0.56g, 0.93mmol) in a 93% yield.  Red powder. 1H NMR (300 MHz, CDCl3/CD3OD*) δ = 7.14 (s, 2H, CH), 6.21 (s, 2H, CH), 5.23 3 3 3 3 m e  was roughly 5 : 1 and CDCl3 was used as reference standard. 2 2 2 2 (s, 2H, meso-CH2), 2.60 (s, 6H, CH3), 2.48-2.39 (q, J = 7.5 Hz, 4H, CH2), 2.33 (s, 6H, CH3), 2.21 (s, 6H, CH ), 0.76-0.70 (t, J = 7.5 Hz, 6H, CH ). 13C NMR (75 MHz, CDCl /CD OD) δ = 156.9, 148.4, 147.6, 142.7, 131.6, 127.4, 125.7, 120.4, 118.2, 24.9, 17.2, 14.3, 13.7, 12.0, 9.8. MS (EI) m/z 440 ([M-2HBr]+). Elemental Anal. Calcd for C29H38Br2N4: C, 57.82; H, 6.36; N, 9.30. Found: C, 57.46; H, 6.30; N, 9.10.     * In all the cases that the ix d solvents were used, the CDCl3/CD3OD ratio  - 121 - bis(5-((3,5-dimethyl-2H-pyrrol-2-ylidene)methyl)-3-hexyl-4-methyl-1H-pyrrol-2-yl) methane dihydrobromide (159-H2·2HBr) N H N NN HHBr HBr C5H11 C5H11  24.7, 24.1, 22.4, 14.2, 13.7, 11.9, 9.9. MS (EI) m/z 552 ([M-2HBr]+). Elemental Anal. 37H54Br2N4: C, 62.18; H, 7.62; N, 7.84. Found: C, 62.55; H, 7.70; N, 7.75.   ) 159-H2·2HBr was prepared in a 91% yield following the synthetic procedure for 158-H2·2HBr. Red powder. 1H NMR (300 MHz, CDCl3/CD3OD) δ = 7.04 (s, 2H, CH), 6.10 (s, 2H, CH), 4.44 (s, 2H, meso-CH2), 2.40 (s, 6H, CH3), 2.40-2.16 (t, J = 7.8 Hz, 4H, CH2), 2.16 (s, 6H, CH3), 2.05 (s, 6H, CH3), 0.91-0.88 (m, 16H, CH2), 0.55-0.49 (t, J = 6.5 Hz, 6H, CH3). 13C NMR (75 MHz, CDCl3/CD3OD) δ = 156.9, 148.6, 147.7, 130.4, 127.4, 125.8, 120.3, 118.2, 31.6, 30.1, 29.8, 29.4, Calcd for C bis(5-((4-ethyl-3,5-dimethyl-2H-pyrrol-2-ylidene)methyl)-3-hexyl-4-methyl-1H- pyrrol-2-yl)methane dihydrobromide (161-H2·2HBr N H N NN HHBr HBr C5H11 C5H11  161-H2·2HBr was prepared in a 93% yield following the synthetic procedure for 158-H2·2HBr. Red powder. 1H NMR (300 MHz, CDCl3/CD3OD) δ = 7.07 (s, 2H, CH), 4.68 (s, 2H, meso-CH2), 2.55 (s, 6H, CH3), 2.41-2.31 (m, 8H, CH2), 2.20 (s, 6H, CH3), 2.15 (s, 6H, CH3), 1.08-0.94 (m,  - 122 - 22H, CH2), 0.65-0.60 (t, J = 6.5 Hz, 6H, CH3). 13C NMR (75 MHz, CDCl3/CD3OD) δ = 156.7, 147.0, 143.7, 142.0, 132.0, 129.6, 127.2, 125.5, 119.5, 31.5, 29.9, 29.3, 24.3, 24.1, 22.4, 16.9, 13.9, 13.6, 12.6, 9.8, 9.7. MS (EI) m/z 608 ([M-2HBr]+). Elemental Anal. Calcd for C41H62Br2N4: C, 63.89; H, 8.11; N, 7.27. Found: C, 63.92; H, 8.02; N, 7.23.   is(5-((4-ethyl-3,5-dimethyl-2H-pyrrol-2-ylidene)methyl)-1H-pyrrol-2-yl) methane b dihydrobromide (165-H2·2HBr) N H N NN HHBr HBr 165-H2·2HBr was prepared in a 95% yield following the synthetic procedure for 158-H2·2HBr. Dark red powder. 1H NMR (300 MHz, DMSO) δ = 12.79 (br s, 2H, NH), 12.55(br s, 2H, NH), 3 3 3 7.76 (br s, 2H, CH), 7.73 (s, 2H, CH), 6.63-6.61(m, 2H, CH), 4.47(s, 2H, meso-CH2), 2.59 (s, 6H, CH3), 2.50-2.42 (q, J = 7.5 Hz, 4H, CH2), 2.30 (s, 6H, CH3), 1.08-1.02 (t, J = 7.5 Hz, 6H, CH ). 13C NMR (75 MHz, CDCl /CD OD) δ = 160.1, 145.8, 133.1, 129.3, 127.6, 124.6, 115.9, 26.5, 16.6, 13.4, 12.5, 9.3. MS (EI) m/z 412 ([M-2HBr]+). Elemental Anal. Calcd for C27H34Br2N4: C, 56.46; H, 5.97; N, 9.75. Found: C, 56.06; H, 5.87; N, 9.68.  - 123 - 4,4'-(ethane-1,2-diyl)bis(3,5-dimethyl-1H-pyrrole-2-carbaldehyde) (172) HN NH O H O H  Method A: To a suspension of dipyrrole ester 166 (0.97g, 2mmol) in THF was added 10% Pd/C catalyst (30mg). After the reaction mixture was exposed to 1.0 atm of H2 overnight, the catalyst was removed by filtration and the solution was collected. The solvent was then removed by rotary evaporation and 168 was obtained quantitively as white solid. After decarboxylation and Vilsmeier-Haack formylation following the synthetic procedure of 155, 172 (0.30g, 1.1mmol) was synthesized in a 55% yield.  a stirred for 10min. The mixture was then warmed to r.t. before H2O as added to allow 172 to precipitate. After filtration and washing with a small amount of EtOH, 72 (0.37g, 1.4mmol) was obtained in a 68% yield. an crystals. Rf (silica; ethyl acetate/CH2Cl2, 1 : 2 ) 0.11. 1H NMR (300 MHz, d6-DMSO) δ = 1.34 (br s, 2H, NH), 9.39 (s, 2H, CHO), 2.40 (s, 4H, CH2), 2.07 (s, 6H, CH3), 1.91 (s, 6H, CH3). C NMR (75 MHz, d6-DMSO) δ = 175.4, 135.5, 127.3, 121.1, 23.9, 10.5, 8.2. Elemental Anal. alcd for  C16H20N2O2: C, 70.56; H, 7.40; N, 10.29. Found: C, 70.00; H, 7.35; N, 10.17. HRMS I, M+) Calcd for C16H20N2O2: 272.15248. Found: 272.15243. Method B: 168 was prepared using the same procedure as method A, but it was then dissolved in TFA (5mL) and stirred for 10 min. at r.t. After cooling in an ice bath, the solution was tre ted with excess CH(OCH3)3 and w 1 T 1 13 C (E  - 124 - 4,4'-(propane-1,3-diyl)bis(3,5-dimethyl-1H-pyrrole-2-carbaldehyde) (173) HN NH O H O H  173 was prepared in a 54% yield following method A used for the synthesis of 172. Method B did not produce 173.  o 1  , CH2). 13C NMR (75 MHz, d6-DMSO) δ = 175.6, 135.0, 127.5, 121.7, 31.1, 23.0, 11.0, 8.6. MS (EI) m/z 286 (M+). Elemental Anal. Calcd for C17H22N2O2: C, 71.30; H, 7.74; N, 9.78. Found: C, 71.26; H, 7.72; N, 9.80.   Tan crystals (mp: 225-226 C). Rf (silica; ethyl acetate/CH2Cl2, 1 : 2 ) 0.16. H NMR (300 MHz, d6-DMSO) δ = 11.37 (br s, 2H, NH), 9.40 (s, 2H, CHO), 2.34-2.27 (t, J = 7.6 Hz, 4H, CH2), 2.16 (s, 6H, CH3), 2.11 (s, 6H, CH3), 1.52-1.40(m, J = 7.6 Hz, 2H 1,2-bis(5-((4-ethyl-3,5-dimethyl-2H-pyrrol-2-ylidene)methyl)-2,4-dimethyl-1H- pyrrol-3-yl)ethane dihydrobromide (174-H2·2HBr) HBr HBr HN NH N N  174-H2·2HBr was prepared in a 90% yield following the synthetic producedure for 158-H2·2HBr.  - 125 - Red solid. 1H NMR (300 MHz, CDCl3/CD3OD) δ = 6.96 (s, 2H, CH), 2.52 (s, 6H, CH3), 2.51 (s, 4H, CH2), 2.38-2.30 (q, J = 7.6 Hz, 4H, CH2), 2.31 (s, 6H, CH3), 2.18 (s, 6H, CH3), 2.00 (s, 6H, CH3), 1.00-0.94 (t, J = 7.6 Hz, 6H, CH3). 13C NMR (75 MHz, CDCl3/CD3OD) δ = 155.0, 151.9, 142.7, 141.7, 131.2, 126.6, 126.5, 125.3, 118.9, 23.7, 16.9, 14.0, 12.4, 11.9, 9.7, 9.5. MS (EI) m/z 482 ([M-2HBr]+). Elemental Anal. Calcd for C32H44Br2N4: C, 59.63; H, 6.88; N, 8.69. Found: C, 9.40; H, 6.83; N, 8.61.  1,3-bis(5-((4-ethyl-3,5-dimethyl-2H-pyrrol-2-ylidene)methyl)-2,4-dimethyl-1H- 5  pyrrol-3-yl)propane dihydrobromide (175-H2·2HBr) HN NH HBr HBr N N  175-H2·2HBr was prepared in an 83% yield following the synthetic producedure for 158-H2·2HBr. Red solid. 1H NMR (300 MHz, CDCl3/CD3OD) δ = 6.97 (s, 2H, CH), 2.49 (s, 6H, CH3), 2.45 (s, 6H, CH3), 2.36-2.27 (m, 8H, CH2), 2.17 (s, 6H, CH3), 2.14 (s, 6H, CH3), 1.53-1.42 (m, J = 7.7 3OD) δ = 154.2, 152.3, 142.3, 141.6, 130.9, 127.7, 126.2, 125.7, 118.7, 29.8, 23.3, 16.9, 13.9, 12.3, 9.8, 9.6. Elemental Anal. Calcd for C33H46Br2N4: C, 60.19; H, 7.04; N, 8.51. Found: C, 59.53; H, 7.06; N, 8.38. HRMS (EI, [M-2HBr+H]+) Calcd for C33H45N4: 497.3644. Found: 497.3650. Hz, 2H, meso-CH2), 0.98-0.92 (t, J = 7.6 Hz, 6H, CH3). 13C NMR (75 MHz, CDCl3/CD  - 126 - 1,2-bis(5-((3,4-dimethyl-2H-pyrrol-2-ylidene)methyl)-2,4-dimethyl-1H-pyrrol-3- yl)ethane dihydrobromide (180-H2·2HBr) HBr HBrHN NH N N  168 (0.26g, 0.85mmol) was dissolved in methanol (5mL) and treated with HBr (0.5mL, 33% in acetic acid) at r.t. After the mixture was stirred for 1h, 177 (0.21g, 1.7mmol) was added. The solution was stirred for another 2h before the addition of diethyl ether (50mL). 180-H2·2HBr (0.42g, 0.72mmol) was obtained by filtration (84%).  Red solid. 1H NMR* (300 MHz, DMSO with a few drops of CD3OD) δ = 7.45 (s, 2H, CH), 7.11 (s, 2H, CH), 2.50 (s, 6H, CH3), 2.36 (t, J = 7.7 Hz, 4H, CH2), 2.18 (s, 6H, CH3), 2.17 (s, 6H,     * 13C NMR could not be performed due to the poor solubility. CH3), 1.94 (s, 6H, CH3), 1.49 (m, 2H, CH2). HRMS (EI, [M-2HBr+H]+) Calcd for C28H35N4: 427.2862. Found: 427.2856.     - 127 - 1,3-bis(5-((3,4-dimethyl-2H-pyrrol-2-ylidene)methyl)-2,4-dimethyl-1H-pyrrol-3-yl)propane dihydrobromide (181-H2·2HBr) HBr HBr HN NH N N  181-H2·2HBr was prepared in an 80% yield following the synthetic procedure for 180-H2·2HBr. Red solid. 1H NMR (300 MHz, CDCl3/CD3OD) δ = 7.45 (s, 2H, CH), 7.11 (s, 2H, CH), 2.50 (s, 6H, CH3), 2.39-2.33 (t, J = 7.7 Hz, 4H, CH2), 2.18 (s, 6H, CH3), 2.17 (s, 6H, CH3), 1.94 (s, 6H, CH3), 1.52-1.46 (m, 2H, CH2). 13C NMR (75 MHz, CDCl3/CD3OD) δ = 156.4, 143.8, 141.9, 139.4, 129.0, 127.2, 126.7, 124.9, 120.9, 29.5, 23.4, 12.8, 10.0, 9.8, 9.6. HRMS (EI, [M-2HBr+H]+) Calcd for C29H37N4: 441.3018. Found: 441.3009.  dimethyl 3,3'-(4,4'-(ethane-1,2-diyl)bis(3,5-dimethyl-1H-pyrrole-4,2-diyl)) bis(2-cyanoacrylate) (182) HN NHNC MeO O CN OMe O To a refluxing methanol (20mL) solution of 172 (0.29g, 1.07mmol) and methyl cyanoacetate at reflux, the methanol was removed by rotary evaporation. Benzene (50mL) was then added to the flask and the reaction mixture was heated to reflux again. A Dean-Stark trap was used to remove the H2O (0.44mL, 5mmol) was added diethylamine (1mL). After stirring for 30min  - 128 - produced in the reaction. After the reaction proceeded for another 2h, the system was cooled to r.t. and 182 (0.32g, 0.74mmol) was collected as a yellow solid by filtration (69%). 1 13 + Bright yellow solid. Rf (silica; ethyl acetate/CH2Cl2, 1 : 8 ) 0.85. H NMR (300 MHz, CDCl3) δ = 9.49 (br s, 2H, NH), 7.90 (s, 2H, CH), 3.87 (s, 6H, OCH3), 2.54 (s, 4H, CH2), 2.08 (s, 6H, CH3), 2.04 (s, 6H, CH3). C NMR (75 MHz, d6-DMSO) δ = 165.0, 138.8, 138.1, 135.5, 123.2, 123.1, 120.2, 85.8, 52.6, 24.3, 11.9, 9.3. MS (EI) m/z 434 (M ). Elemental Anal. Calcd for C24H26N4O4: C, 66.34; H, 6.03; N, 12.89. Found: C, 66.54; H, 6.01; N, 12.81.  dimethyl 3,3'-(4,4'-(propane-1,3-diyl)bis(3,5-dimethyl-1H-pyrrole-4,2-diyl))  bis(2-cyanoacrylate) (183) HN NH CN NC OO OMeMeO f 2 2 3 /z 9. Found: C, 67.19; H, 6.31; N, 12.48. 183 was prepared in a 83% yield following the synthetic procedure for 182. Bright yellow solid. R  (silica; ethyl acetate/CH Cl , 1 : 8 ) 0.85. 1H NMR (300 MHz, CDCl ) δ = 9.51 (br s, 2H, NH), 7.92 (s, 2H, CH), 3.87 (s, 6H, OCH3), 2.44-2.38 (t, J = 7.8 Hz, 4H, CH2), 2.29 (s, 6H, CH3), 2.16 (s, 6H, CH3), 1.61-1.50 (m, 2H, CH2). 13C NMR (75 MHz, d6-DMSO) δ = 165.0, 138.7, 138.0, 135.3, 124.0, 123.4, 120.3, 85.4, 52.5, 30.8, 23.7, 12.3, 9.6. MS (EI) m 448 (M+). Elemental Anal. Calcd for C25H28N4O4: C, 66.95; H, 6.29; N, 12.4  - 129 - (2,2')-dimethyl 3,3'-(5,5'-methylenebis(1H-pyrrole-5,2-diyl))bis(2-cyanoacrylate) NH HN H HNC O O CN O O  Method A: Pyrrole 192 (1.76g, 10mmol) and dimethoxymethane (0.5mL, 5.5mmol) were dissolved in CH Cl  (50mL). After the solution was chilled to -10 oC, it was treated with boron trifluoride diethyl etherate (10mmol, 1.25mL). The reaction mixture was stirred at this temperature for 3h before it was quenched with aqueous Na CO . The mixture was extracted with CH Cl  and the organic layer was collected and condensed. The product was isolated on silica gel using ethyl acetate and hexanes (1:4) as eluent. 193 (0.6g) was obtained as a bright yellow solid (33%). Method B: To a methanol solution of 163 (0.2g, 1mmol) and methyl cyanoacetate (0.44mL, 5mmol) was added NEt3 (1mL) at r.t. The reaction mixture was stirred for 2h before the solvent as removed under reduced pressure. After chromatography, 193 (0.09g, 0.25mmol) was btained in a 25% yield.  MHz, d6-DMSO) δ = 12.05 (br s, 2H, NH), 8.08 (s, 2H, CH), 7.39-7.38 (d, J = 4.0 Hz, 2H, pyrrole-H), 6.35-6.34  13C NMR (75 MHz, d6-DMSO) δ = 163.9, 142.3, 139.0, 126.3, 118.4, 117.3, 113.2, 89.3, 52.6, 26.2. MS (EI) m/z 364 (M ). HRMS (EI, M ) Calcd for C19H16N4O4: 364.11785. Found: 364.11716. 2 2 2 3 2 2 w o Bright yellow solid. Rf (silica; ethyl acetate/CH2Cl2, 1 : 8 ) 0.40. 1H NMR (300 (d, J = 4.0 Hz, 2H, pyrrole-H), 4.14 (s, 2H, meso-CH2), 3.78 (s, 6H, OCH3). + +  - 130 - 4,4'-methylenebis(1H-pyrrole-2-carbaldehyde) (201) HN NH H H O O  o a solution of 195 (2.49g, 10mmol) and dimethoxymethane (0.46ml, 5mmol) in anhydrous rate (1.25mL, 10mmol). The solution was then heated to 60 oC and stirred for 10h. The reaction was quenched with aqueous NaHCO3 and the solution was extracted with ethyl acetate (2 x 100mL). After drying over anhydrous Na2SO4 and evaporation, the reaction mixture was separated by column eluent, unreacted pyrrole-2-carboxaldehyde 191 was recovered. Further elution with ethyl acetate and methylene chloride (1:4) provided 201 (0.60g, 3mmol) in a 30% yield. 9.93 (br s, 2H, NH), 9.42 (d, J = .7 Hz, 2H, CHO), 6.97 (m, 2H, β-H), 6.82 (m, 2H, α-H), 3.69 (s, 2H, meso-CH2). 13C NMR (75 Hz, d6-DMSO) δ = 178.9, 132.6, 125.7, 125.3, 119.9, 23.5. MS (EI) m/z 202 (M+). Elemental nal. Calcd for C11H10N2O2: C, 65.34; H, 4.98; N, 13.85. Found: C, 65.53; H, 5.15; N, 14.00. olidinium perchlorate (202) T acetonitrile (50mL) was added boron trifluoride diethyl ethe chromatography on silica gel. Using CH2Cl2 initially as White crystals (mp: 153-154 oC). Rf (silica; ethyl acetate/hexanes, 1 : 2 ) 0.13. 1H NMR (300 MHz, d6-DMSO) δ = 11.87 (br s, 2H, NH), 9.39 (s, 2H, CHO), 7.04 (s, 2H, β-H), 6.82 (s, 2H, α-H), 3.62 (s, 2H, meso-CH2). 1H NMR (300 MHz, CD3CN) δ = 0 M A  (E)-1-(4-(1H-pyrrol-2-yl)but-3-en-2-ylidene)pyrr N H N ClO4  - 131 - 202 was prepared quantitatively from 195 by dissolving 195 in acetone.  o 1 13 Yellow crystals (mp: 228-230 C). H NMR (300 MHz, CD3CN) δ = 10.29 (br s, 1H, NH), 7.77-7.72 (d, J = 15.4 Hz, 1H, CH), 7.25 (br s, 1H, pyrrole-H), 6.92 (br s, 1H, pyrrole-H), 6.67-6.62 (d, J = 15.4 Hz, 1H, CH), 6.39-6.37 (m, 1H, pyrrole-H), 3.91-3.84 (q, J = 6.5 Hz, 4H, CH2), 2.44 (s, 3H, CH3), 2.11-2.01 (m, 4H, CH2). C NMR (75 MHz, d6-DMSO) δ = 171.4,  -2-carbaldehyde) (203) 140.6, 129.7, 128.6, 121.3, 112.1, 111.6, 52.9, 52.3, 24.2, 24.0, 17.4. MS (ESI) m/z 189 ( [M _ ClO4]+). Elemental Anal. Calcd for C12H17ClN2O4: C, 49.92; H, 5.93; N, 9.70. Found: C, 50.29; H, 5.90; N, 9.76.  4,4'-(phenylmethylene)bis(1H-pyrrole HN NH O H O H  203 was prepared in a 46% yield following the synthetic procedure for 201. an crystals (mp: 201 oC). Rf (silica; ethyl acetate/hexanes, 1 : 2 ) 0.15. 1H NMR (300 MHz, H, Ph-H), 6.95 (s, 2H, β-H), 6.81 (s, 2H, α-H), 5.26 (s, 1H, meso-CH). 13C NMR (75 MHz, d6-DMSO) δ = 179.2, 78 (M+). Elemental Anal. Calcd for C17H14N2O2: C, 73.37; H, 5.07; N, 10.07. Found: C, 73.43; H, 5.23; N, 10.18. T d6-DMSO) δ = 11.97 (br s, 2H, NH), 9.40 (s, 2H, CHO), 7.35-7.10 (m, 5 145.4, 132.6, 129.6, 128.3, 128.0, 126.0, 125.3, 119.7, 41.3. MS (EI) m/z 2  - 132 - 4,4'-((perfluorophenyl)methylene)bis(1H-pyrrole-2-carbaldehyde) (204) HN NH O H O H F F F F F  204 was prepared in a 41% yield following the synthetic procedure for 201. 1Amorphous. Rf (silica; ethyl acetate/hexanes, 1 : 2 ) 0.19. H NMR (300 MHz, CDCl3) δ = 10.80 (br s, 2H, NH), 9.43 (s, 2H, CHO), 7.08 (s, 2H, β-H), 6.91 (s, 2H, α-H), 5.69 (s, 1H, meso-CH). F NMR (282 MHz, CDCl3) δ = -141.8(d, J = 16.0 Hz, 2F), -156.4 (t, J = 20.6 Hz, 1F), -161.8 (m, 2F). C NMR (75 MHz, CDCl3) δ = 179.6, 147-135 (4C, the peaks were split due to 13C-19F coupling), 132.7, 126.1, 125.7, 120.9, 118-117 (1C, the peak was split due to 13C-19F coupling), 31.1. MS (EI) m/z 367.9(M+). Elemental Anal. Calcd for C17H9F5N2O2: C, 55.45; H, 2.46; N, 7.61. Found: C, 55.18; H, 2.81; N, 7.48. 4,4'-((4-methoxyphenyl)methylene)bis(1H-pyrrole-2-carbaldehyde) (205) 19 13   HN NH O H O H O  205 was prepared in a 38% yield following the synthetic procedure for 201.  - 133 - Amorphous. Rf (silica; ethyl acetate/hexanes, 1 : 2 ) 0.13. 1H NMR (300 MHz, CDCl3) δ = 10.67 r s, 2H, NH), 9.39 (s, 2H, CHO), 7.18-7.15 (d, J = 8.8 Hz, 2H, Ar-CH), 6.90 (s, 2H, β-H), so-CH), 3.80 (s, 3H, OCH3). 13C NMR (75 MHz, CDCl3) δ = 179.5, 158.1, 136.4, 132.6, 130.7, 129.2, 126.0, 121.4, 308.1164.   4,4'-(mesitylmethylene)bis(1H-pyrrole-2-carbaldehyde) (206) (b 6.87-6.85 (d, J = 8.8 Hz, 2H, Ar-CH), 6.80 (s, 2H, α-H), 5.24 (s, 1H, me 113.8, 55.2, 41.1. HRMS (EI, M+) Calcd for C18H16N2O3: 308.1161. Found: HN NH O H O H  206 was prepared in a 17% yield following the synthetic procedure for 201. morphous. Rf (silica; ethyl acetate/hexanes, 1 : 2 ) 0.19. 1H NMR (300 MHz, CDCl3) δ = 9.97 r s, 2H, NH), 9.43 (s, 2H, CHO), 6.89 (d, J = 1.1 Hz, 2H, β-H), 6.87 (s, 2H, Ar-H), 6.84 (br s, H, CH3). 13C NMR (75 MHz, CDCl3) δ = 179.3, 136.6, 136.1, 132.6, 130.2, 128.5, 125.4, 121.1, 36.3, 21.4, 20.8. HRMS (EI, [M + H]+) Calcd for C20H21N2O2: 321.1603. Found: 321.1606.    A (b 2H, α-H), 5.72 (s, 1H, meso-CH), 2.29 (s, 3H, CH3), 2.13 (s, 6   - 134 - Pentafluorobenzaldehyde dimethyl acetal (207) O O F F F F F  Pentafluorobenzaldehyde (2g, 10mmol) and trimethyl orthoformate (5mL) were added into a 25mL round-bottom flask. After the solid was dissolved, 0.3g catalyst142 (HClO4 on silica) was dded to the solution which was subsequently heated at 50 oC overnight. Once all the starting aterial was consumed, the reaction mixture was passed through a silica column using CH2Cl2 as eluent. 207 was quantitatively obtained as a colourless oil. Colourless oil. 1H NMR (300 MHz, CDCl3) δ = 5.58 (s, 1H, CH), 3.47 (s, 6H, OCH3). 19F NMR 13 13C-19F coupling), 98.9, 55.1. MS (EI) m/z 242 (M+). Elemental Anal. Calcd for C9H7O2F5: C, 44.64; H, 2.91. Found: C, 45.00; H, 2.98.   Mesitaldehyde dimethyl acetal (208) a m (282 MHz, CDCl3) δ = -142.64 (m, 2F), -153.89 (m, 1F), -162.20 (m, 2F). C NMR (75 MHz, CDCl3) δ = 147-111 (5 C, the peaks were split due to the O O  208 was prepared according to the synthetic procedure for 207 and used directly in the subsequent reaction.   - 135 - 4,4'-((4-nitrophenyl)methylene)bis(1H-pyrrole-2-carbaldehyde) (212) HN NH O H O H NO2  Tan crystals (mp: 155-156 oC). Rf (silica; ethyl acetate/hexanes, 1 : 2 ) 0.083. 1H NMR (300 MHz, CDCl3) δ = 10.24 (br s, 2H, NH), 9.44 (d, J = 1.5 Hz, 2H, CHO), 8.20-8.17 (d, J = 8.8 Hz, 2H, Ar-H), 7.44-7.40 (d, J = 8.1 Hz, 2H, Ar-H), 6.90 (br s, 2H, β-H), 6.79-6.77 (t, J = 2.2 Hz, 2H, α-H), 5.42 (s, 1H, meso-CH). 13C NMR (75 MHz, CDCl3) δ = 179.5, 151.7, 146.7, 133.0, 129.2, 128.6, 125.4, 123.9, 120.6, 41.9. MS (EI) m/z 323 (M+). Elemental Anal. Calcd for 17H13N3O4: C, 63.16; H, 4.05; N, 13.00. Found: C, 62.81; H, 4.06; N, 12.88.  4,4'-((4-(methoxycarbonyl)phenyl)methylene)bis(1H-pyrrole-2-carbaldehyde) (213) 212 was prepared in a 68% yield following the synthetic procedure for 201. C  HN NH O H O H OO  213 was prepared in a 55% yield following the synthetic procedure for 201. Brown crystals (mp: 161-163 oC). Rf (silica; ethyl acetate/hexanes, 1 : 2 ) 0.09. 1H NMR (300 MHz, CDCl3) δ = 10.09 (br s, 2H, NH), 9.43 (s, 2H, CHO), 8.01-7.98 (d, J = 8.1 Hz, 2H, Ar-H),  - 136 - 7.33-7.31 (d, J = 8.1 Hz, 2H, Ar-H), 6.88 (br s, 2H, β-H), 6.78 (br s, 2H, α-H), 5.35 (s, 1H meso-CH), 3.91 ,  (s, 3H, COOCH3). 13C NMR (75 MHz, CDCl3) δ = 179.4, 166.9, 149.4, 132.8, 129.9, 129.4, 128.6, 128.3, 125.4, 120.8, 52.1, 42.0. HRMS (EI, M+) Calcd for C19H16N2O4: 36.1110. Found: 336.1113.  3    4,4'-((4-chlorophenyl)methylene)bis(1H-pyrrole-2-carbaldehyde) (214) HN NH O H O H Cl  214 was prepared in a 39% yield following the synthetic procedure for 201. 9.8, 129.6, 128.6, 25.8, 121.1, 41.3. MS (EI) m/z 312 (M+). Elemental Anal. Calcd for C17H13N2O2Cl: C, 65.29; , 4.19; N, 8.96. Found: C, 65.04; H, 4.36; N, 8.64.  Amorphous. Rf (silica; ethyl acetate/hexanes, 1 : 2 ) 0.16. 1HN MR (300 MHz, CD3CN) δ = 9.99 (br s, 2H, NH), 9.42 (d, J = 0.7 Hz, 2H, CHO), 7.33-7.30 (d, J = 8.8 Hz, 2H, Ar-H), 7.27-7.24 (d, J = 8.8 Hz, 2H, Ar-H), 6.88 (br s, 2H, β-H), 6.77 (t, J = 2.2 Hz, 2H, α-H), 5.30 (s, 1H, meso-CH). 13C NMR (75 MHz, CDCl3) δ = 179.5, 142.7, 132.7, 132.3, 12 1 H    - 137 - 4,4'-(p-tolylmethylene)bis(1H-pyrrole-2-carbaldehyde) (215) HN NH O H O H  215 was prepared in a 35% yield following the synthetic procedure for 201. 1 13 + Amorphous. Rf (silica; ethyl acetate/hexanes, 1 : 2 ) 0.16. HNMR (300 MHz, CDCl3) δ = 10.93 (br s, 2H, NH), 9.40 (s, 2H, CHO), 7.15 (m, 4H, Ar-H), 6.94 (s, 2H, β-H), 6.83 (s, 2H, α-H), 5.26 (s, 1H, meso-CH), 2.35 (s, 3H, CH3). C NMR (75 MHz, CDCl3) δ = 179.5, 141.2, 136.0, 132.5, 130.4, 129.1, 128.0, 126.3, 121.6, 41.4, 20.8. HRMS (EI, M ) Calcd for C18H16N2O2: 292.1212. Found: 292.1211. 4,4'-((2,6-dichlorophenyl)methylene)bis(1H-pyrrole-2-carbaldehyde) (216)   HN NH O H O H Cl Cl  216 was prepared in a 35% yield following the synthetic procedure for 201 except that chloroform was used as solvent. Brown crystals. Rf (silica; ethyl acetate/hexanes, 1 : 2 ) 0.24. 1H NMR (300 MHz, d6-DMSO) δ = 12.02 (br s, 2H, NH), 9.42 (s, 2H, CHO), 7.48-7.45 (d, J = 8.1 Hz, 2H, Ar-H), 7.32-7.28 (t, J =  - 138 - H), 6.98 (s, 2H, β-H), 6.83 (s, 2H, α-H), 6.12 (s, 1H, meso-CH). 13C NMR (75 8.1 Hz, 1H, Ar- MHz, d6-DMSO) δ = 179.3, 138.7, 134.8, 132.4, 129.8, 129.2, 125.4, 125.0, 119.6, 37.7. MS (EI) m/z 346 (M+).  Elemental Anal. Calcd for C17H12N2O2Cl2: C, 58.81; H, 3.48; N, 8.07. Found: C, 58.76; H, 3.66; N, 8.42.   4,4'-(ethane-1,1-diyl)bis(1H-pyrrole-2-carbaldehyde) (217) HN NH H O H O  217 was prepared in a 25% yield following the synthetic procedure for 201. .3 Hz, 1H, meso-CH), 1.53-1.51 (d, J = 6.6 Hz, 3H, CH3). 13C NMR (75   Tan crystals (mp: 135-136 oC). Rf (silica; ethyl acetate/hexanes, 1 : 2 ) 0.15. 1H NMR (300 MHz, CD3CN) δ = 9.89 (br s, 2H, NH), 9.42 (s, 2H, CHO), 6.96-6.95 (m, 2H, β-H), 6.84-6.83 (m, 2H, α-H), 4.03-3.97 (q, J = 7 MHz, CD3CN) δ = 180.0, 133.5, 124.6, 119.5, 118.4, 30.6, 23.2. MS (EI) m/z 216 (M+). Elemental Anal. Calcd for C12H12N2O2: C, 66.65; H, 5.59; N, 12.96. Found: C, 66.83; H, 5.66; N, 12.68.   - 139 - bis(5-((3,4-diethyl-2H-pyrrol-2-ylidene)methyl)-1H-pyrrol-3-yl)methane dihydrobromide (220-H2·2HBr) HN NH N NHBr BrH  218 (0.5g, 2.2mmol) was dissolved in methanol (20mL) and heated to reflux before the addition of aqueous NaOH (1g in 2mL H  2O). After stirring at reflux for 2h, the mixture was cooled to r.t. nd extracted with hexanes. The solvent was then removed by rotary evaporation and 219 was btained as a light brown oil. To a THF (2mL) solution of 201 (0.20g) was added the . After the solution was cooled to -50 oC under argon, HBr (0.25 mL, 33% in Red powder. H NMR  (300 MHz, CD3OD, 25 C) δ = 8.02 (s, 2H; CH), 7.88 (s, 2H; CH), 7.85 (s, 2H; CH), 7.77 (s, 2H; CH), 4.00 (s, 2H; meso-CH2), 2.86-2.78 (q, J = 7.6 Hz, 4H; CH2), 2.61-2.54 (q, J = 7.6 Hz, 4H; CH2), 1.28-1.21 (m, 12H; CH3).MS (EI) m/z 412 ([M - 2HBr]+). HRMS (EI) Calcd for C27H32N4 ([M - 2HBr]+): 412.2627. Found: 412.2626.   * The lifetime of 220-H2·2HBr in solution is not long enough to allow the taking of a C NMR spectrum, although it is stable in the solid state. a o newly-made 219 acetic acid) was added dropwise and the reaction mixture was stirred at -50 oC for 20 min. before 50mL diethyl ether was added to precipitate the product. The dark red 220-H2·2HBr was collected by filtration (94%). 1 * o 13  - 140 - Co 220  (221) Co[(Py) Cl ]Cl (0.48g, 1mmol) was initially dissolved in a solution (30mL) of CHCl  and MeOH (1 : 1, v : v). Once the proligand 220-H ·2HBr (originally from 0.2g 201) was filtered, it was immediately transferred to the Co3+ solution. After shaking the mixture for 1 or 2 minutes to fully dissolve the 220-H2·2HBr, the mixture was then added rapidly to a refluxing solution (50mL) of CHCl3 and MeOH (1 : 1, v : v), and several drops of triethylamine were quickly 2 2 1 (s, 6H; meso-CH2), 2.69-2.51 (m,, 2H; CH2), 2.21-2.38 (m, 12H; CH2), 1.17-1.12 (t, J = 7.7 Hz, 18H; CH3), 0.96-0.91 (t, J = 7.5 z, 18H; CH3). 13C NMR (75 MHz, CD2Cl2, 25 oC) δ = 152.0, 150.0, 145.5, 134.3, 133.8, 133.3, 27.3, 30.3, 18.9, 18.5, 17.7, 15.0.MS (MALDI-TOF) m/z 1348.7 (M+). 2 3 4 2 3 2 added. The reaction mixture was stirred under reflux for another 15 min. before the removal of solvents. Using CH2Cl2 as eluent, the mixture was passed through a short silica column and the red fractions were collected. Subsequently, chromatography was performed on a 1 meter long silica column using CH Cl  / hexanes (1 : 1, v : v) as eluent. After the removal of solvents, 221 was obtained as red powder from the first fraction in a 26% yield. Red powder. Rf (silica; CH2Cl2/hexanes, 1 : 1 ) 0.73. 1H NMR (300 MHz, CD2Cl2, 25 oC) δ = 7.17 (s, 6H; CH), 6.80 (s, 6H; CH), 5.69 (br s, 6H; CH), 3.5 1 H 133.2, 129.4, 1   - 141 - Co22203 (222) 222 was obtained as red powder from the second fraction of the Co22203 mixture in a 16% yield. Red powder. Rf (silica; CH2Cl2/hexanes, 1 : 1 ) 0.69. 1H NMR (300 MHz, CD2Cl2, 25 oC) δ = 7.17 (s, 6H; CH), 6.83 (s, 6H; CH), 5.76 (s, 6H; CH), 5.68 (s, 6H; CH), 3.38-3.33 (d, J = 13.9 Hz, 3H; meso-CH), 3.27-3.23 (d, J = 13.9 Hz, 3H; meso-CH), 2.62-2.59 (m, 12H; CH2), .33-2.23 (m, 12H; CH2), 1.14 (t, J = 7.3 Hz, 18H; CH3), 0.94 (t, J = 7.5 Hz, 18H; CH3). 13C MR (75 MHz, CD2Cl2, 25 oC) δ = 152.4, 150.0, 145.6, 135.8, 134.6, 134.2, 134.1, 127.9, (M+).   ) 0.73. 1H NMR* (300 MHz, CD2Cl2) δ = 20.18 (s), 16.66 (s), 11.86 (s), 9.63 (s), 9.25 (s), 7.19 (s), -6.81 (s), -25.09 (br s), -26.51 (br s). MS (MALDI-TOF) m/z 1342.6 (M+). HRMS (EI) Calcd for C H N 56Fe  ([M + H]+): 1343.6188. Found: 1343.6161.    2 N 127.3, 30.3, 18.9, 18.5, 17.7, 15.0.  MS (MALDI-TOF) m/z 1348.8 Fe22203 (223) 223 was prepared following the procedure for 221, except FeCl3 was used instead of Co[(Py)4Cl2]Cl. After chromatography, 223 was obtained as dark red powder from the first fraction in a 13% yield. Dark red powder. Rf (silica; CH2Cl2/hexanes, 1 : 1 81 91 12 2  - 142 - Fe22203 (224) 224 was obtained as dark red powder from the 22203 mixture in a 9% s), 7.46 (s), 5.36, -6.98 (s), -23.93 (br s), -24.73 (br s). MS (MALDI-TOF) m/z 1342.7 (M+). HRMS (EI) Calcd for C H N 56Fe  ([M + H]+): 1343.6188. Found: 1343.6217.   Mn 220  (225) 225 was prepared following the procedure for 221, except Mn(OAc)3 was used instead of Co[(Py)4Cl2]Cl. 225 was isolated as a diastereomeric mixture on alumina using CH2Cl2 as eluent and obtained as dark red powder in a 36% yield. Dark red powder. R  (alumina; CH Cl /hexanes, 1 : 1 ) 0.94. MS (MALDI-TOF) m/z 1340.7 (M+). HRMS (EI) Calcd for C81H91N1255Mn2 ([M + H]+): 1341.6251. Found: 1341.6265.    second fraction of the Fe yield. Dark red powder. Rf (silica; CH2Cl2/hexanes, 1 : 1 ) 0.69. 1H NMR* (300 MHz, CD2Cl2) δ = 19.89 (s), 12.13 (s), 10.16 (s), 9.53 (s), 9.32 ( 81 91 12 2 2 3 f 2 2   * The spectrum shows broad peaks due to the paramagnetism of Fe3+.  - 143 - Ga22203 (226) 226 was prepared following the procedure for 221, except Ga(OAc)3 was used instead of Co[(Py)4Cl2]Cl. 226 was isolated as a diastereomeric mixture on alumina using CH2Cl2 as eluent. The ratio of helicate to mesocate is roughly 3 : 2. 226 was obtained as red powder in a 38% yield. Red powder. Rf (alumina; CH2Cl2/hexanes, 1 : 1 ) 0.94. 1H NMR (300 MHz, CD2Cl2, 25 oC) δ = .06 (s, helicate-CH and mesocate-CH), 6.77 (s, helicate-CH and mesocate-CH), 6.33 (s, -CH), 3.57 (s, meso-CH2 of the helicate), 3.45-3.40 (d, J = 13.9 Hz, meso-CH2 of the mesocate), 3.28-3.24 (d, J = 14.3 Hz, , CH ), 0.99-0.94 (t, J = 7.7 Hz, CH ). MS (MALDI-TOF) m/z 1371.3 (M+). HRMS (EI) Calcd for C H N 69Ga  ([M + H]+): 1369.6001. Found: 1369.6035.   In 220  (227) 227 was prepared following the procedure for 221, except InCl3 was used instead of Co[(Py)4Cl2]Cl. 227 was isolated as a diastereomeric mixture on alumina using CH2Cl2 as eluent. The ratio of helicate to mesocate is roughly 3 : 2. 227 was obtained in a 32% yield. Red powder. Rf (alumina; CH2Cl2/hexanes, 1 : 1 ) 0.94. 1H NMR (300 MHz, CD2Cl2, 25 oC) δ = 7.06 (s, helicate-CH and mesocate-CH), 6.86 (s, mesocate-CH), 6.85-6.84 (m, helicate-CH and 7 helicate-CH and mesocate-CH), 6.23 (s, mesocate-CH), 6.21 (s, helicate meso-CH2 of the mesocate), 2.62-2.55 (q, J = 7.4 Hz, CH2), 2.37-2.21 (m, CH2), 1.17-1.11 (m 3 3 81 91 12 2 2 3  - 144 - mesocate-CH), 6.76 (s, helicate-CH), 6.55 (s, helicate-CH), 6.53 (s, mesocate-CH), 3.66 (s, meso-CH2 of the helicate), 3.53-3.48 (d, J = 14.6 Hz, meso-CH2 of the mesocate), 3.42-3.37 (d, J = 14.6 Hz, meso-CH2 of the mesocate), 2.64-2.57 (q, J = 7.4 Hz, CH2), 2.43-2.23 (m, CH2), 1.17-1.12 (t, J = 7.5 Hz, CH3), 1.04-0.99 (t, J = 7.7 Hz, CH3). MS (MALDI-TOF) m/z 1460.6 (M+). HRMS (EI) Calcd for C81H91N12115In2 ([M + H]+): 1461.5567. Found: 1461.5533.   ethyl 4-ethyl-5-fluoro-3-methyl-1H-pyrrole-2-carboxylate (232) N H F O O xture was then heated t 40 oC for 10h before it was quenched with aqueous Na2CO3. After extraction, the mixture was oncentrated and separated on silica gel using CH2Cl2 and hexanes (3 : 1) as eluent. 232 (1.0g, Light brown crystals (mp: 97-98℃). Rf (silica; CH2Cl2) 0.84. 1H NMR (300 MHz, d6-acetone) δ = 10.94 (br s, 1H, NH), 4.27-4.20 (q, J = 7.1 Hz, 2H, CH2), 2.45-2.38 (q, J = 7.6 Hz, 2H, CH2), 2.27 (s, 3H, CH3), 1.31-1.26 (t, J = 7.0 Hz, 3H, CH3), 1.08-1.03 (t, J = 7.5 Hz, 3H, CH3). 19F NMR (282 MHz, d6-acetone) δ = -37.71(s, 1F). 13C NMR (75 MHz, CDCl3) δ = 161.4, 127.3, To a CH2Cl2 solution of N-fluorobenzenesulfonimide (NFSI) (3.15g, 10mmol) were added ZrCl4 (THF complex, 2mmol) and 231 (1.81g, 10mmol). The sealed reaction mi a c 5mmol) was obtained as light brown crystals (50%). 123.8, 118.4, 117.3, 60.7, 17.5, 14.8, 14.8, 10.9. MS (EI) m/z 200 ([M + H]+).   - 145 - 5,5'-methylenebis(1H-pyrrole-5,2-diyl)bis(phenylmethanone) (236) NH HN Ph Ph O O  236 was prepared following the synthetic procedure for 201, but the reaction was performed at 0 ixture was separated on silica gel using ethyl acetate and hexanes (1 : Light brown crystals (mp: 195 oC). Rf (silica; ethyl acetate/hexanes, 1 : 2) 0.33. 1H NMR (300 MHz, d6-acetone) δ = 11.15 (br s, 2H, NH), 7.87-7.84 (m, 4H, Ph-H), 7.61-7.47 (m, 6H, Ph-H), 6.79-6.77 (dd, J = 3.7 Hz, J’ = 2.6 Hz, 2H, pyrrole-H), 6.20-6.18 (dd, J = 3.7 Hz, J’ = 2.6 Hz, , 138.7, 132.3, 131.7, 129.6, 129.2, 120.6, 110.5, 26.9. MS (EI) m/z 354 (M+). HRMS (EI) Calcd for C23H18N2O2 (M+): 354.13683. Found: 354.13598.   (4-((5-benzoyl-1H-pyrrol-2-yl)methyl)-1H-pyrrol-2-yl)(phenyl)methanone (237) oC for 1h. The reaction m 4) as eluent. 236 was obtained in a 4% yield. 2H, pyrrole-H), 4.27 (s, 2H, meso-CH2). 13C NMR (75 MHz, d6-acetone) δ = 184.2, 140.0 NH NH Ph Ph O O  237 was generated in the same reaction which produced 236. 237 was obtained in a 20% yield. Light brown crystals (mp: 198 oC). Rf (silica; ethyl acetate/hexanes, 1 : 2) 0.22.  1H NMR (300 MHz, d6-acetone) δ = 10.95 (br s, 2H, NH), 7.88-7.81 (m, 4H, Ph-H), 7.62-7.46 (m, 6H, Ph-H),  - 146 - 7.22-7.20 (q, J = 1.5 Hz, 1H, pyrrole-H), 6.85-6.84 (m, 1H, pyrrole-H), 6.75-6.73 (dd, J = 3.7 Hz, J’ = 2.4 Hz, 1H, pyrrole-H), 6.11-6.09 (dd, = 3.7 Hz, J’ = 2.6 Hz, 1H, pyrrole-H), 4.02 (s, , 132.2, 131.9, 129.6, 129.5, 129.2, 125.3, 124.1, 120.8, 119.8, 109.8, 25.9. MS (EI) m/z 354 (M+). Elemental Anal. Calcd for C H N O : C, 77.95; H, 5.12; N, 7.90. Found: C, 77.67; H, 5.24; N, 7.88.  4,4'-methylenebis(1H-pyrrole-4,2-diyl)bis(phenylmethanone) (238) J 2H, meso-CH2). 13C NMR (75 MHz, d6-acetone) δ = 184.5, 141.9, 141.7, 140.1, 139.9, 132.4 23 18 2 2  HN NH Ph Ph O O  238 was generated in the same reaction which produced 236. 238 was obtained in a 12% yield. Light brown crystals (mp: 211-213 oC). Rf (silica; ethyl acetate/hexanes, 1 : 2) 0.20.  1H NMR (300 MHz, d6-acetone) δ = 10.85 (br s, 2H, NH), 7.86-7.83 (m, 4H, Ph-H), 7.61-7.46 (m, 6H, 2 NMR (75 MHz, 6  Calcd for C23H18N2O2: C, 77.95; H, 5.12; N, 7.90. Ph-H), 7.12-7.10 (m, 2H, pyrrole-H), 6.76-6.75 (m, 2H, pyrrole-H), 3.76 (s, 2H, meso-CH ). 13C d -acetone) δ = 184.5, 140.0, 132.3, 129.6, 129.5, 129.2, 127.0, 124.9, 119.6, 24.9. MS (EI) m/z 354 (M+). Elemental Anal. Found: C, 77.61; H, 5.26; N, 7.76.    - 147 - 4,4'-methylenebis(1H-pyrrole-4,2-diyl)bis((perfluorophenyl)methanone) (239) HN NH O O F F F FF F F F F F   was prepared following the synthetic procedure for 201, but the reaction was performed at as eluent. 239 was obtained in a 18% yield. White crystals (mp: 221-222 oC). Rf (silica; ethyl acetate/hexanes, 1 : 2) 0.45. 1H NMR (300 ), 13 13 19 + + ((2,6-dichloroph 239 r.t. for 20 min. The reaction mixture was separated on silica gel using ethyl acetate and hexanes (1 : 4) MHz, CD3CN) δ = 10.22 (br s, 2H, NH), 7.10-7.09 (m, 2H, pyrrole-H), 6.63 (m, 2H, pyrrole-H 3.63 (s, 2H, meso-CH2). C NMR (75 MHz, CD3CN) δ = 172.6, 146.6-132.3 (Ar-C, the peaks were split due to C- F coupling), 128.2, 127.8, 122.0, 118.4, 24.3. MS (EI) m/z 534 (M ). HRMS (EI) Calcd for C23H8N2O2F10 (M ): 534.04261. Found: 534.04278.   5,5'-methylenebis(1H-pyrrole-5,2-diyl)bis enyl)methanone) (240) NH HN O O Cl Cl Cl Cl  240 was prepared following the synthetic procedure for 201, but the reaction was performed at t. for 40 min. The reaction mixture was separated on silica gel using ethyl acetate and hexanes r. (1 : 4) as eluent. 240 was obtained in a 2% yield.  - 148 - White crystals. Rf (silica; ethyl acetate/hexanes, 1 : 2) 0.44. 1H NMR (300 MHz, d6-acetone) δ = 11.29 (br s, 2H, NH), 7.50-7.49 (m, 6H, Ar-H), 6.44 (s, 2H, pyrrole-H), 6.14-6.13 (m, 2H, pyrrole-H), 4.26 (s, 2H, meso-CH2). 13C NMR (75 MHz, d6-acetone) δ = 180.0, 139.9, 138.9, 132.9, 132.0, 131.8, 129.2, 121.3, 111.2, 27.0. MS (EI) m/z 492 (M+). Elemental Anal. Calcd for C23H14Cl4N2O2: C, 56.13; H, 2.87; N, 5.69. Found: C, 55.83; H, 2.97; N, 5.79.   (4-((5-(2,6-dichlorobenzoyl)-1H-pyrrol-2-yl)methyl)-1H-pyrrol-2-yl)(2,6-dichlorophenyl) methanone (241) NH NH O Cl Cl O Cl Cl  241 was generated in the same reaction which produced 240. 241 was obtained in a 12% yield. 0 MHz, d6-acetone) δ = 11.19 (br s, 1H, NH), 11.12 (br s, 1H, NH), 7.50-7.46 (m, 6H, Ar-H), 7.26 (s, 1H, pyrrole-H), White crystals. Rf (silica; ethyl acetate/hexanes, 1 : 2) 0.35. 1H NMR (30 6.49 (s, 1H, pyrrole-H), 6.39 (s, 1H, pyrrole-H), 6.02-6.00 (m, 1H, pyrrole-H), 3.95 (s, 2H, meso-CH2). 13C NMR (75 MHz, d6-acetone) δ = 179.7, 143.2, 138.9, 132.9, 132.8, 132.1, 132.0, 131.8, 129.2, 129.1, 127.0, 124.4, 121.4, 120.3, 110.5, 25.8. MS (EI) m/z 492 (M+). HRMS (EI) Calcd for C23H1435Cl4N2O2 (M+): 489.98094. Found: 489.98105.  - 149 - 4,4'-methylenebis(1H-pyrrole-4,2-diyl)bis((2,6-dichlorophenyl)methanone) (242) HN NH O O Cl Cl Cl Cl White crystals (mp: 230 242 was generated in the same reaction which produced 240. 242 was obtained in a 11% yield. N2O2: C, 56.13; H, 2.87; N, 5.69. Found: C, 55.98; H, 2.88; N, 5.54.    oC). Rf (silica; ethyl acetate/hexanes, 1 : 2) 0.31. 1H NMR (300 MHz, d6-acetone) δ = 11.07 (br s, 2H, NH), 7.49-7.47 (m, 6H, Ar-H), 7.12 (m, 2H, pyrrole-H), 6.34 (s, 2H, pyrrole-H), 3.65 (s, 2H, meso-CH2). 13C NMR (75 MHz, d6-acetone) δ = 180.0, 139.0, 132.8, 131.9, 129.2, 129.2, 127.1, 126.4, 120.1, 24.4. MS (EI) m/z 492 (M+). Elemental Anal. Calcd for C23H14Cl4  5,5'-methylenebis(1H-pyrrole-5,2-diyl)bis(mesitylmethanone) (243) NH HN O O  243 was prepared following the synthetic procedure for 201, but the reaction was performed at 0 C for 2h. The reaction mixture was separated on silica gel using ethyl o acetate and hexanes (1 : 4) as eluent. 243 was obtained in a 3% yield. 1White crystals. Rf (silica; ethyl acetate/hexanes, 1 : 2) 0.44. H NMR (300 MHz, d6-DMSO) δ = 12.03 (br s, 2H, NH), 6.88 (s, 4H, Ar-H), 6.17 (s, 2H, pyrrole-H), 5.96 (s, 2H, pyrrole-H), 4.01  - 150 - (s, 2H, meso-CH2), 2.26 (s, 6H, CH3), 2.05 (s, 12H, CH3). 13C NMR (75 MHz, d6-DMSO) δ = 187.0, 138.3, 137.3, 137.3, 133.6, 131.8, 127.9, 119.4, 109.6, 25.7, 20.7, 19.0. MS (EI) m/z 438 (M+). HRMS (EI) Calcd for C29H30N2O2 (M+): 438.23073. Found: 438.22971.   esityl(4-((5-(2,4,6-trimethylbenzoyl)-1H-pyrrol-2-yl)methyl)-1H-pyrrol-2-yl)methanone m (244) NH NH O O  White crystals. R 244 was generated in the same reaction which produced 243. 244 was obtained in a 13% yield. yl acetate/hexanes, 1 : 2) 0.31. 1H NMR (300 MHz, d6-DMSO) δ = 11.89 (br s, 1H, NH), 11.84 (br s, 1H, NH), 7.06 (s, 1H, pyrrole-H), 6.88(s, 2H, Ar-H), 6.86 (s, 2H, Ar-H), 6.21 (s, 1H, pyrrole-H), 6.11 (s, 1H, pyrrole-H), 5.82 (s, 1H, pyrrole-H), 3.72 (s, 2H, meso-CH2). 13C NMR (75 MHz, d6-DMSO) δ = 187.3, 186.7, 141.5, 137.4, 137.4, 137.2, 133.5, 132.0, 131.4, 127.9, 127.8, 125.2, 122.9, 119.6, 118.6, 108.8, 24.6, 20.7, 19.0, 18.9. MS (EI) m/z 438 (M+). HRMS (EI) Calcd for C29H30N2O2 (M+): 438.23073. Found: 438.23083.     f (silica; eth  - 151 - 4,4'-methylenebis(1H-pyrrole-4,2-diyl)bis(mesitylmethanone) (245) HN NH O O  245 was generated in the same reaction which produced 243. 245 was obtained in a 10% yield. s, 6H, CH3), 1.61 (s, 12H, CH3). 13C NMR (75 MHz, nd: C, 9.36; H, 6.85; N, 6.44. bis(5-(phenyl(1H-pyrrol-2-yl)methyl)-1H-pyrrol-3-yl)methane (248) White crystals (mp: 212 oC). Rf (silica; ethyl acetate/hexanes, 1 : 2) 0.29. 1H NMR (300 MHz, d6-acetone) δ = 10.36 (br s, 2H, NH), 6.58 (s, 2H, pyrrole-H), 6.43 (s, 4H, Ar-H), 5.72 (s, 2H, pyrrole-H), 3.16 (s, 2H, meso-CH2), 1.84 ( d6-acetone) δ = 188.5, 138.6, 134.9, 133.7, 128.9, 126.9, 125.0, 119.0, 24.5, 21.2, 19.5. MS (EI) m/z 438 (M+). Elemental Anal. Calcd for C29H30N2O2: C, 79.42; H, 6.89; N, 6.39. Fou 7   HN NH NH HN 238 (1.0g, 2.8mmol) in MeOH (30mL) was treated with excess NaBH4 in several portions. Once the starting material was consumed, the solvent was removed by rotary evaporation. H2O and CH2Cl2 were then added to the flask to dissolve the mixture. After extraction, the organic layer was collected and dried. The removal of CH2Cl2 quantitatively provided 246 as a viscous liquid.  - 152 - Subsequently, 246 was redissolved in pyrroles (50mL) and treated with TFA (0.22mL, 2.9mmol) at r.t. The reaction was allowed to proceed for 15 min. before the addition of aqueous NaOH. The reaction mixture was washed, dried and separated on silica gel using hexanes and CH2Cl2 (1 : 1) as eluent. 248 (1.06g, 2.3mmol) was obtained in an 82% yield. Viscous oil. Rf (silica; CH2Cl2) 0.45. 1H NMR (300 MHz, d6-acetone) δ = 9.60 (br s, 2H, NH), 9.20 (br s, 2H, NH), 7.29-7.15 (m, 10H, Ph-H), 6.68-6.65 (m, 2H, pyrrole-H), 6.45-6.43 (m, 2H, pyrrole-H), 6.00-5.97 (dd, J = 5.9 Hz, J’ = 2.9 Hz, 2H, pyrrole-H), 5.76-5.67 (m, 2H, pyrrole-H), 5.67-5.66 (t, J = 1.8 Hz, 2H, pyrrole-H), 5.38 (s, 2H, CH), 3.53 (s, 2H, meso-CH2). C NMR (75 MHz, CD2Cl2) δ = 143.1, 133.2, 133.0, 129.1, 128.8, 127.3, 125.0, 117.7, 115.2, 108.7, 108.4, 107.5, 44.7, 25.4. MS (EI) m/z 456 (M ). HRMS (EI) Calcd for C31H28N4 (M ): 456.23140. Found: 456.23116.   bis(5-((perfluorophenyl)(1H-pyrrol-2-yl)methyl)-1H-pyrrol-3-yl)methane (249) 13 + + HN NH NH HN F F F F F F F F F F  249 was prepared following the synthetic procedure of 248 except that BF3 was used at 0 oC for the condensation of 247 and pyrrole. 249 was obtained in an 80% yield.  - 153 - Viscous oil. Rf (silica; CH2Cl2) 0.56. 1H NMR (300 MHz, d6-acetone) δ = 9.81 (br s, 2H, NH), o-CH2). 13C NMR (75 MHz, d6-acetone) δ = 147.7-136.9 (Ar-C, the peaks were split due to 13C-19F coupling), 129.7, 129.4, 124.7, 118.5, 116.3, 108.8, 108.6, 107.9, 34.3, 25.8. MS (EI) m/z 636 (M+). HRMS (EI) Calcd for C H F N  (M+): 636.13718. Found: 636.13667.  bis(5-((Z)-phenyl(2H-pyrrol-2-ylidene)methyl)-1H-pyrrol-3-yl)methane (250-H2) 9.47 (br s, 2H, NH), 6.72-6.70 (m, 2H, pyrrole-H), 6.50 (s, 2H, pyrrole-H), 6.04-6.01 (dd, J = 6.0 Hz, J’ = 2.7 Hz, 2H, pyrrole-H), 5.95 (s, 2H, pyrrole-H), 5.89(s, 2H, pyrrole-H), 5.87 (s, 2H, pyrrole-H), 3.56 (s, 2H, mes 31 18 10 4  HN NH N N To a CH2Cl2 solution of 249 (1.0g, 2.2mmol) was added DDQ (1.0g, 4.4mmol). The reaction mixture was then sealed and stirred at r.t. for 3h. After the solvent was removed, the product was isolated on silica gel. Elution with hexanes and CH2Cl2 (1 : 1) provided 250-H2 (0.45g, .0mmoL) in a 45% yield. p: 166-168 oC). Rf (silica; ethyl acetate/hexanes, 1 : 4) 0.59. 1H NMR (300 MHz, le-H), 6.30-6.29 (dd, J = 4.0 Hz, J' = 2.2 Hz, 2H, pyrrole-H), 3.59 (s, 1 Brown solid (m CD2Cl2) δ = 12.64 (br s, 2H, NH), 7.69-7.68 (d, J = 1.1 Hz, 2H, pyrrole-H), 7.50-7.44 (m, 10H, Ph-H), 7.38-7.37 (m, 2H, pyrrole-H), 6.41 (d, J = 1.1 Hz, 2H, pyrrole-H), 6.39-6.37 (dd, J = 4.0 Hz, J' = 1.1 Hz, 2H, pyrro  - 154 - 2H, meso-CH2). 13C NMR (75 MHz, CD2Cl2) δ = 153.9, 146.1, 142.2, 137.9, 136.9, 136.1, 134.7, 131.2, 129.5, 129.3, 128.1, 124.7, 114.1, 25.1. MS (EI) m/z 452 (M+). HRMS (EI) Calcd for C31H24N4 (M+): 452.20010. Found: 452.19982.   Fe22503 (251) The proligand 250-H2 (50mg, 0.11mmol) was initially dissolved in chloroform (1mL) and then added to methanol (50mL) at reflux. With heating, FeCl3, which had been dissolved in methanol (2mL), was added to the solution, followed by the addition of a few drops of NEt3. The mixture was stirred and heated at reflux for another 2h before the removal of solvent. After hromatography on alumina using hexanes and CH2Cl2 (1 : 1) as eluent, 251 was obtained as a iastereomeric mixture in an 31% yield. 63.3 (M+). HRMS (ESI) Calcd for C93H67N1256Fe2 ([M + H]+): 1463.4310. Found: 1463.4326.   Co22503 (252) 252 was prepared following the synthetic procedure for 251, except Co[(Py)4Cl2]Cl was used instead of FeCl3. 252 was obtained as a diastereomeric mixture in a 9% yield. The ratio of c d Dark red powder. Rf (alumina; CH2Cl2/hexanes, 1 : 1 ) 0.83. MS (MALDI-TOF) m/z 14 helicate to mesocate is roughly 4 : 1.  - 155 - Red powder. Rf (alumina; CH2Cl2/hexanes, 1 : 1 ) 0.83. 1H NMR (300 MHz, CD2Cl2, 25 oC) δ = 7.53-7.39 (m, Ph-H of the helicate and mesocate), 6.69-6.67 (dd, J = 3.9 Hz, J’ = 2.0 Hz, pyrrole-H of the helicate), 6.65-6.63 (dd, J = 4.2 Hz, J’ = 1.3 Hz,  pyrrole-H of the mesocate), 6.47 (d, J = 1.4 Hz, pyrrole-H of the helicate), 6.43 (d, J = 1.5 Hz, pyrrole-H of the mesocate), 6.32 (s, pyrrole-H of the helicate), 6.31-6.29 (dd, J = 3.5 Hz, J’ = 2.0 Hz, pyrrole-H of the helicate), 6.28 (d, J = 1.8 Hz, pyrrole-H of the mesocate), 6.21 (d, J = 1.5 Hz, pyrrole-H of the helicate), 6.17 (s, pyrrole-H of the mesocate), 6.10 (d, J = 1.8 Hz, pyrrole-H of the mesocate), 3.44 (s, meso-CH2 of the helicate), 3.26 (s, meso-CH2 of the mesocate). MS (MALDI-TOF) m/z 469.6 (M+). HRMS (ESI) Calcd for C93H67N1259Co2 ([M + H]+): 1469.4241. Found: 1469.4236.  253 was prepared following the synthetic procedure for 251, except Mn(OAc)3 was used instead of FeCl3. 253 was obtained as a diastereomeric mixture in a 74% yield. Dark red powder. Rf (alumina; CH2Cl2/hexanes, 1 : 1 ) 0.83. MS (MALDI-TOF) m/z 1461.8 (M+). HRMS (ESI) Calcd for C93H67N1255Mn2 ([M + H]+): 1461.4373. Found: 1461.4353.  1  Mn22503 (253)  - 156 - Ga22503 (254) 254 was prepared following the synthetic procedure for 251, except Ga(NO3)3 was used instead of FeCl3. 254 was obtained as a diastereomeric mixture in a 71% yield. The ratio of helicate to mesocate is roughly 2 : 1. Red powder. Rf (alumina; CH2Cl2/hexanes, 1 : 1 ) 0.83. 1H NMR (300 MHz, CD2Cl2, 25 oC) δ = 7.51-7.34 (m, Ph-H of the helicate and mesocate), 6.80 (s, pyrrole-H of the helicate), 6.74 (d, J =1.5 Hz, pyrrole-H of the helicate), 6.70 (d, J = 1.1 Hz, pyrrole-H of the mesocate), 6.61 (s, pyrrole-H of the mesocate), 6.56-6.54 (dd, J = 4.0 Hz, J' = 1.1 Hz, pyrrole-H of the helicate), 6.54-6.52 (dd, J = 4.0 Hz, J' = 1.5 Hz, pyrrole-H of the mesocate), 6.38 (d, J = 1.1 Hz, pyrrole-H of the helicate), 6.33 (d, J = 1.1 Hz, pyrrole-H of the mesocate), 6.24-6.22 (dd, J = 4.0 Hz, J' = 1.5 Hz, pyrrole-H of the helicate), 6.22-6.20 (dd, J = 4.4 Hz, J' = 1.8 Hz, pyrrole-H of the mesocate), 3.47 (s, meso-CH2 of the helicate), 3.33-3.29 (dd, J = 14.3 Hz, meso-CH of the esocate), 3.27-3.23 (dd, J = 14.0 Hz, meso-CH of the mesocate). MS (MALDI-TOF) m/z +). HRMS (ESI) Calcd for C93H67N1269Ga2 ([M + H]+): 1489.4123. Found: 1489.4102.  In22503 (255) 255 was prepared following the synthetic procedure for 251, except InCl3 was used instead of m 1491.7 (M  FeCl3. 255 was obtained as a diastereomeric mixture in a 34% yield. The ratio of helicate to mesocate is roughly 2 : 1.  - 157 - Red powder. Rf (alumina; CH2Cl2/hexanes, 1 : 1 ) 0.83. 1H NMR (300 MHz, CD2Cl2, 25 oC) δ = 7.51-7.34 (m, Ph-H of the helicate and mesocate), 7.20 (d, J = 1.1 Hz, pyrrole-H of the mesocate), 7.06 (s, pyrrole-H of the helicate), 7.03 (d, J = 1.1 Hz, pyrrole-H of the helicate), 6.84 (s, pyrrole-H of the mesocate), 6.57-6.55 (dd, J = 4.4 Hz, J' = 1.1 Hz, pyrrole-H of the helicate), 6.54-6.53 (d, J = 1.1 Hz, pyrrole-H of the mesocate), 6.41-6.40 (d, J = 0.8 Hz, pyrrole-H of the elicate), 6.35-6.34 (d, J = 1.1 Hz, pyrrole-H of the mesocate), 6.31-6.29 (dd, J = 4.0 Hz, J' = 1.4 z, pyrrole-H of the helicate), 6.29-6.27 (dd, J = 4.2 Hz, J' = 1.6 Hz, pyrrole-H of the mesocate), he helicate), 3.40-3.35 (dd, J = 14.3 Hz, meso-CH of the mesocate), h H 3.52 (s, meso-CH2 of t 3.35-3.28 (dd, J = 14.3 Hz, meso-CH of the mesocate). MS (MALDI-TOF) m/z 1581.5 (M+). HRMS (ESI) Calcd for C93H67N12115In2 ([M + H]+): 1581.3689. Found: 1581.3739.   (4-(2-(5-benzoyl-1H-pyrrol-2-yl)propan-2-yl)-1H-pyrrol-2-yl)(phenyl)methanone (256) NH NH O O 256 was prepared following the synthetic procedure for 201, but the reaction was performed at 80 oC for 1h. The reaction mixture was separated on silica gel using ethyl acetate and hexanes (1 : 4) as eluent. 256 was obtained in a 20% yield. White crystals (mp: 214 oC). Rf (silica; ethyl acetate/hexanes, 1 : 2) 0.36. 1H NMR (300 MHz, CDCl3) δ = 10.11 (br s, 1H, NH), 9.63 (br s, 1H, NH), 7.87 (s, 2H, Ph-H), 7.85 (d, 2H, Ph-H),  - 158 - 7.57-7.43 (m, 6H, Ph-H), 6.97-6.95 (dd, J = 2.9 Hz, J’ = 1.8 Hz, 1H, pyrrole-H), 6.81-6.79 (dd, J .3, 35.0, 30.0. MS (ESI) m/z 383 ([M+1]+). Elemental Anal. Calcd for C25H22N2O2: C, 78.51; H, 5.80; N, 7.32. Found: C, 78.41; H, 5.90; N, 7.24.  = 3.8 Hz, J’ = 2.4 Hz, 1H, pyrrole-H), 6.77-6.75 (m, 1H, pyrrole-H), 6.19-6.17 (dd, J = 3.8 Hz, J’ = 2.8 Hz, 1H, pyrrole-H), 1.72 (s, 6H, CH3). 13C NMR (75 MHz, CDCl3) δ = 184.7, 184.4, 149.4, 138.5, 138.2, 134.0, 131.8, 131.5, 131.0, 130.1, 128.9, 128.9, 128.3, 128.2, 122.5, 120.5, 116.9, 107  (4,4'-(propane-2,2-diyl)bis(1H-pyrrole-4,2-diyl))bis(phenylmethanone) (257) HN NH O O  257 was generated in the same reaction which produced 256. 257 was obtained in a 22% yield. White crystals (mp: 213-214 oC). Rf (silica; ethyl acetate/hexanes, 1 : 2) 0.33. 1H NMR (300 MHz, CDCl3) δ = 9.91 (br s, 2H, NH), 7.89-7.86 (m, 4H, Ph-H), 7.59-7.45 (m, 6H, Ph-H), z, J’ = 1.7 Hz, 2H, pyrrole-H), 6.77-6.76 (dd, J = 2.6 Hz, J’ = 1.8 Hz, lemental Anal. Calcd for C25H22N2O2: C, 6.98-6.96 (dd, J = 2.8 H 2H, pyrrole-H), 1.63 (s, 6H, CH3). 13C NMR (75 MHz, CDCl3) δ = 184.5, 140.0, 132.3, 129.6, 129.5, 129.2, 127.0, 124.9, 119.6, 24.9. MS (EI) m/z 382 (M+). HRMS (EI) Calcd for C25H22N2O2 (M+): 382.16813. Found: 382.16784. E 78.51; H, 5.80; N, 7.32. Found: C, 77.84; H, 5.81; N, 7.23. 4,4'-(propane-2,2-diyl)bis(2-(phenyl(1H-pyrrol-2-yl)methyl)-1H-pyrrole) (259)  - 159 - HN NH NH HN 259 was prepared following the synthetic procedure for 248 except that 0 oC was used for the condensation of 258 and pyrrole. 259 was obtained in an 83% yield. z 484 (M+). HRMS (EI) Calcd for C33H32N4 (M+): 484.26270. Found: 484.26347.   Viscous oil. Rf (silica; CH2Cl2) 0.45. 1H NMR (300 MHz, CD3CN) δ = 8.83 (br s, 2H, NH), 8.45 (br s, 2H, NH), 7.31-7.19 (m, 10H, Ph-H), 6.64-6.62 (dd, J = 4.4 Hz, J’ = 2.6 Hz, 2H, pyrrole-H), 6.37-6.36 (m, 2H, pyrrole-H), 6.02-6.00 (dd, J = 5.9 Hz, J’ = 2.9 Hz, 2H, pyrrole-H), 5.78-5.77 (m, 2H, pyrrole-H), 5.70-5.68 (t, J = 1.8 Hz, 2H, pyrrole-H), 1.44 (s, 6H, CH3). 13C NMR (75 MHz, CDCl3) δ = 142.2, 135.4, 132.7, 131.9, 128.4, 128.4, 126.7, 117.2, 112.8, 108.1, 107.2, 106.3, 44.1, 33.6, 31.2. MS (EI) m/ 4,4'-(propane-2,2-diyl)bis(2-(phenyl(2H-pyrrol-2-ylidene)methyl)-1H-pyrrole) (260-H2) HN NH N N 260-H2 was prepared following the synthetic procedure of 250-H2 except that chloranil instead of DDQ was used in the oxidation. 260-H2 was obtained in an 87% yield.  - 160 - Red solid (mp: 89-91 oC). Rf (silica; ethyl acetate/hexanes, 1 : 4) 0.64.1H NMR (300 MHz, CD2Cl2) δ = 12.56 (br s, 2H, NH), 7.71 (d, J = 1.1 Hz, 2H, pyrrole-H), 7.51-7.43 (m, 10H, Ph-H), 7.35-7.34 (m, 2H, pyrrole-H), 6.42 (d, J = 1.1 Hz, 2H, pyrrole-H), 6.37-6.35 (dd, J = 3.8 Hz, J’ = 1.3 Hz, 2H, pyrrole-H), 6.29-6.28 (dd, J = 3.8 Hz, J’ = 2.0 Hz, 2H, pyrrole-H), 1.46 (s, 6H, CH3). 13C NMR (75 MHz, CD2Cl2) δ = 153.6, 146.8, 146.4, 141.1, 137.9, 136.7, 133.8, 131.3, 129.3, 128.2, 126.8, 124.2, 113.7, 34.6, 29.6. MS (EI) m/z 480 (M+). HRMS (EI) Calcd for C33H28N4 (M+): 480.23140. Found: 480.23120.   Fe22603 helicate (261) 261 was prepared from 260-H2 and FeCl3 following the synthetic procedure for 251. After chromatography on alumina, Fe22603 was isolated as a diastereomeric mixture in a 52% yield. Recrystallization by vapour diffusion of hexanes into a CH2Cl2 solution provided 261 as red crystals. Red crystals. Rf (alumina; CH2Cl2/hexanes, 1 : 1 ) 0.86. MS (MALDI-TOF) m/z 1547.6 (M+). HRMS (ESI) Calcd for C99H79N1256Fe2 ([M + H]+): 1547.5249. Found: 1547.5215.    - 161 - Co22603 helicate (262) 262 was prepared from 260-H2 e synthetic procedure for 251. hy on alumina, Co22603 was isolate reomeric mixture in a 28% icate to mesocate is roughly 8 : 1  provided 262 as red Rf (alumina; CH2Cl2/hexanes, 1 : 1 ) 0. 00 MHz, CD2Cl2) δ = .55-7.35 (m, 30H, Ph-H), 6.64-6.62 (dd, 2 Hz, J’ = 1.3 Hz, 6H, pyrrole-H), 6.49-6.48 (d, J = 1.8 Hz, 6H, pyrrole-H), 6.32 (m, 6H, pyrrole-H), 6.29-6.27 (dd, J = 4.2 Hz, J’ = 1.6 Hz, 6H,  J = 1.4 Hz, 6H, pyrrole-H), 1.12 (s, 18H, CH3). 13C NMR (75 MHz, CD2Cl2) δ = 153.0, 150.4, 145.7, 141.2, 138.8, 1 35.2, 13 31.1, 130.9, 129.0, 127.9, 127.5, 118.1, 34.7, 30.6. MS (MALDI-TOF) m/z 1553.6 (M+). HRMS (ESI) Calcd for C99H79N1259Co2 +): 1553.5215. Found: 1553.5247.   and Mn(OAc)3 following the synthetic procedure for 251. After y on alumina, Mn22603 was isolated as a ereomeric mixture in a 58% yield.  dark red crystals. ; CH2Cl2/hexanes, 1 : 1 ) 0.86. MS (MALDI-TOF) m/z 1545.3 H79N1255Mn2 ([M + H]+ ound: 1545.5298. and Na3[Co(NO2)6] following th After chromatograp d as a diaste yield. The ratio of hel . Recrystallization crystals. Red crystals. 86. 1H NMR (3 7 J = 4. pyrrole-H), 6.14 (d, 35.6, 1 2.3, 1 ([M + H]  Mn22603 helicate (263) 263 was prepared from 260-H2 chromatograph  diast Recrystallization provided 263 as Dark red crystals. Rf (alumina (M+). HRMS (ESI) Calcd for C99 ): 1545.5312. F  - 162 - Ga22603 helicate (264) 264 was prepared from 260 2 and Ga(NO3)3 following the synthetic procedure for 251. After chrom phy on alum 3 was isolated as a diaster ixture in a 70% yield. The ra licate to m s roughly 8 : 1. Recrystallization provided 264 as red crystals.  Red crystals. Rf (alum Cl2/hexanes, 1 : 1 ) 0.86. 1H 00 MHz, C ) δ = 7.53-7.33 (m, 30H, Ph-H), 6.90 (m, 6H, ), 6.64 ( .4 Hz, 6H, e-H), 6.51-6.50 (dd, J = 4.0 H 1.1 Hz, 6 -H), 6.41 .5 Hz, 6H, e-H), 6.22-6.20 (dd, J = 4.0 H 5 Hz, 6H, ), 1.16 (s, 3). 13C NMR (75 MHz, CD2Cl  149.4, 147  142.9, 13 , 132.2, 131.2, 131.0, 128.9, 127.8, 127.5, 115.9, 34.2, 31.3. MS (MALDI-TOF) m/z +). HRMS lcd for C99 69Ga2 ([M + H]+): 1573.5062. Found: 1573.5035.   In22603 helicate (265) 265 was prepared from 260-H2 and InCl3 following the synthetic procedure for 251. After chromatography on alumina, In22603 was isolated as a diastereomeric mixture in a 29% yield. The ratio of helicate to mesocate is roughly 8 : 1. Red powder. Rf (alumina; CH2Cl2/hexanes, 1 : 1 ) 0.86. 1H NMR (300 MHz, CD2Cl2) δ = 7.49-7.33 (m, 30H, Ph-H), 7.24 (s, 6H, pyrrole-H), 6.85 (s, 6H, pyrrole-H), 6.51-6.50 (d, J = 3.3 Hz, 6H, pyrrole-H), 6.43 (s, 6H, pyrrole-H), 6.31-6.29 (m, 6H, pyrrole-H), 1.19 (s, 18H, CH3). -H atogra ina, Ga2260 eomeric m tio of he esocate i ina; CH2  NMR (3 D Cl2 2  pyrrole-H d, J = 1  pyrrol z, J’ = H, pyrrole  (d, J = 1  pyrrol z, J’ = 1.  pyrrole-H  18H, CH 2) δ = .7, 146.9, 9.4, 139.3 1575.8 (M  (ESI) Ca H79N12  - 163 - 13C NMR (75 MHz, CD2Cl2) δ = 150.0, 148.8, 148.1, 143.0, 141.1, 140.9, 140.1, 133.5, 131.2, .8, 127.7, 116.4, 34.3, 31.8. MS (MAL  m/z 1665.4 (M+). HRMS (ESI) In2 ([M + H]+): 1665.4628. Found: 1665.4596. 131.1, 129.2, 128 DI-TOF) Calcd for C99H79N12155  - 164 - 3.3 Crystal Data Table 3.1. Crystal data for 201. Empir rmula C11H10ical Fo N2O2 Formu ight 202.21 Crystal Colour, Habit Colourless, tablet Crystal Dimensions /mm 0.15 X 0.20 X 0.35 Crystal System Orthor Space Group P ca21 a/Å 18.894(1) b/Å 4.5121(3) c/Å 11.5662(8) α/ 90.0 β/ 90.0 γ/ 90.0    Lattic eters V 986.1(1 Z Va 4 Dcalc/g cm-3 1.362 F000 424.00 µ(MoKα) /cm-1 0.96 Temperature /K 173 Total: 8050 No. of Reflections Measure Unique: 2311 (Rint = 0.023) No. Observations (I>0.00σ(I)) 2311 No. Variables 144 R1; wR2 (refined on F2, all data) 0.039; 0.085 Goodness of Fit Indicator (GOF) 1.04 No. of Observations (I>2σ(I)) 2069 R1; wR2 (refined on F, I>2σ(I)) 0.033; 0.081 la We  hombic    (# 29) deg deg deg e Param /Å3 ) lue  - 165 - Table 3.2.  Atomic coordinat pic displacement parameters (A^2 x 10^3) for 201. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.  y z U(eq) es ( x 10^4) and equivalent isotro x C(1) 3042(1)   14617(4) 5199(2) 32(1) C(2) 2696(1) 12576(3) 5952(1) 26(1) 2051(1) 11125(3) 5804(1) 26(1) C(4) 1923(1) 9410(3) 6800(1) 26(1) 2496(1) 9880(3) 7517(2) 31(1) 1272(1) 7593(3) 7057(2) 30(1) C(7) 88(1) 10146(4) 6528(2) 31(1) C(8) 637(1) 36(3) 1) 26(1) C(9) 502(1) 29(3) 1) 27(1) C(10) -116(1) 12831(3) 8094(1) 26(1) C(11) -462(1) 30(4) ) 32(1) 2958(1) 11766(3) 7011(1) 30(1) N(2) -364(1) 12118(3) 7014(1) 29(1) O(1) 3608(1) 15877(3) 5386(1) 39(1) O(2)   -1012(1) 7(3) (1) 39(1)  C(3) C(5) C(6) 95 7288( 112 8277( 149 8830(2 N(1) 1625 8608  - 166 - Table 3.3. Crystal data for 202. Empirical Formula C12H17N2O4Cl Formula Weight 288.73 Crystal Colour, Habit Red, p Crysta sions /mm 0.05 X 0.10 X 0.20 Crystal System Monoc Space Group P 21/n a/Å 8.8704(4) b/Å 15.030(1) c/Å 10.2274(7) α/ 90.0 β/deg 93.762(2) γ/d 90.0    Lattic eters V 1360.6 Z Val 4 Dcalc/ 1.410 F000 608.00 µ(Mo -1 2.93 Temp  /K 173 T 8839 No. o tions Mea U 2343 ( 5) No. Observations (I>0.0 2343 No. Variables 187 R1; w d on F2, 0.092; Good  Indicato 1.05 No. o I> 1694 R1; w ined on F, I 066; rism l Dimen linic  (# 14) deg eg e Param /Å3 (2) ue g cm-3  Kα) /cm erature otal: f Reflec sure nique: Rint = 0.04 0σ(I)) R2 (refine all data)  0.182 ness of Fit r (GOF) f Observations ( 2σ(I)) R2 (ref >2σ(I)) 0.  0.165    - 167 - Table 3.4. Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 202. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.  x y z U(eq)  occ C(1) 7314(5) 10454(3) -3015(4) 48(1) C(2) 8469(5) 10989(3) -2520(5) 51(1) C(3) 8610(5) 10834(3) -1174(4) 41(1) C(4) 7561(5) 10203(3) -875(4) 35(1) C(5) 7387(5) 9786(3) 364(4) 38(1) C(6) 6425(5) 9111(3) 593(4) 40(1) C(7) 6295(5) 8695(3) 1811(4) 39(1) C(8) 7193(6) 9002(3) 3016(5) 54(1) C(9) 4504(5) 7582(3) 818(4) 39(1) C(10) 3924(13) 6724(6) 1401(6) 48(2) (2) 47(2) (2) C(10B) 49(7) (2) C(11B) 53(7) (2) 0.66 C(11) 3889(10) 6937(6) 2848(6) 0.66 C(12) 5283(5) 7510(3) 3139(4) 45(1) N(1) 6779(4) 9987(2) -2034(3) 37(1) N(2) 5420(4) 8002(2) 1901(3) 34(1) Cl(1) 8891(1) 6578(1) 1517(1) 37(1) O(1) 8953(5) 7468(3) 1138(5) 91(2) O(2) 7409(4) 6266(3) 1207(5) 92(2) O(3) 9241(6) 6458(4) 2872(4) 106(2) O(4) 9902(3) 6044(2) 823(3) 51(1) 3514(9) 6927(5) 1486(9) 0.34 4326(8) 6700(5) 2787(9) 0.34    - 168 - Table 3.5. Crystal data for 221. Empirical Formula C84H96Cl6N12Co2 Formula Weight 1604.29 Crystal Colour, Habit Red, pr Cryst nsions 0.10 X 0.12 X 0.50 Cryst  Triclin Space Group P -1 ( a/Å 13.7050(9) b/Å 17.5163(9) c/Å 17.8828(11) α/d 81.878 β/deg 76.930(3) γ/ 83.402    Lattic eters V 4124.5 Z Val 2 Dcalc/ 1.292 F000 1680.0 µ(Mo -1 6.47 Temp  /K 173 T 44178 No. o ctions Meas U 12657 48) No. Observations (I>0.0 12657 No. Variables 970 R1; w ned on F2, 0.0975; 0.1966 Goo it Indicat 1.085 No. o ations (I> 8912 R1; w ned on F, (0.0651; 0.1821) ism al Dime al System ic #2) eg (3) e Param (3) deg /Å3 (4) ue g cm-3 0 Kα) /cm erature otal: f Refle ure nique:  (Rint = 0.0 0σ(I)) R2 (refi  all data) or (GOF) dness of F 2σ(I)) f Observ R2 (refi I>2σ(I))   - 169 - Table 3.6. Atomic coordinate ic displacement parameters (A^2 x 10^3) for 221. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.  y z U(eq)  occ s ( x 10^4) and equivalent isotrop x C(1) 2989(4) 4904(3) 2418(3) 33(1) C(2) 3190(4) 5666(3) 2460(3) 34(1) 3291(4) 5681(3) 3202(3) 33(1) C(4) 3168(3)     4919(3) 3592(3)     26(1) 3269(4) 4636(3) 4328(3) 32(1) 3208(3)   3884(3) 25(1) C(7) 3368(4) 3582(3) 5415(3) 31(1) C(8) 3281(3) 2792(3) 5510(3) 28(1) C(9) 3039(3) 2647(3) 4827(3) 25(1) C(10) 3414(4) 2204(3) 6185(3) 34(1) C(11) 1529(3) 1943(3) 6583(2) 24(1) 2557(4) 1688(3) 6462(3) 27(1) C(13) 2604(4) 903(3) 6671(3) 31(1) C(14) 1606(3) 700(3) 6924(3) 24(1) C(15) 1291(4) (3) 7208(3) 25(1) C(16) 332(3) -238(2) 7473(2) 21(1) C(17) -6(4) 9(3) (3) 23(1) 8) -1038(4) -889(3) 7977(2) 23(1) C(19) -1296(4) -91(2) 7778(2) 20(1) 3270(60) 6320(60) 1810(60) 49(3) 0.5 C(21) 2987(10) 6208(7) 82(7) 40(3) 0.5 C(22) 3476(5) 6371(3) 3544(4) 50(2) 4590(6) 6468(4) 3417(5) 77(2) 649(4) -1723(3) 7873(3) 33(1) C(25) 878(5) -2160(3) 7169(4) 58(2) 9(4) (3) 33(1) 2(5) ) 57(2) C(28) 4856(4) 3510(3) 2660(3) 31(1) ) 3088(3) 2357(3) 33(1) 5552(4) 2329(3) 2459(3) 35(1) C(31)   4527(4) 2309(3) 2830(3)   27(1) 1669(3) 31(1) 1655(2) 3351(3) 26(1) C(34) 2388(4) 1003(3) 3559(3) 27(1) ) 1264(2) 3841(2) 21(1) 2077(2)    22(1) C(37)      519(3) 815(2) 4109(2) 21(1) C(3) C(5) C(6) 4686(3) C(12) -35 -97 7787 C(1 C(20) 11 C(23) C(24) C(26) -175 C(27) -281 -1487 8325(3) -1156(3 8655(4) C(29) 5762(4 C(30) C(32) 3973(4) 3037(3) C(33)   2967(4) C(35) 1421(3 C(36) 1420(4)  3801(2)  - 170 - Table 3.6. Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 221. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor. (continued) U(eq) c x y z  oc C(38) 196(3) 1069(2) 5533(2) 18(1) C(39) -132(3) 1001(2) 4861(2) 18(1) C(40) -1160(3) 1086(2) 5061(2) 22(1) C(41) -1438(3) 1203(2) 5858(3) 20(1) C(42) -2388(3) 1309(2) 6307(3) 24(1) C(43) -2653(3) 1438(2) 7068(3) 22(1) C(44) -3630(4) 1488(3) 7555(3) 27(1) C(45) -3510(4) 1615(3) 8265(3) 27(1) C(46) -2472(3) 1637(2) 8200(3) 25(1) C(47) 6720(4) 3437(3) 1 -4 ) 953(4) 9533(4) 1813(5) 3675(3) 1196(3) 38(1) C(58) 1621(4) 3669(3) 2021(3) 31(1) C(59) 754(4) 3889(3) 2513(3) 34(1) C(60) 578(4) 3909(3) 3290(3) 28(1) C(61) -338(4) 4090(3) 3814(3) 34(1) C(62) -156(4) 4018(2) 4539(3) 27(1) C(63) 880(3) 3792(2) 4453(3) 25(1) C(64) -885(4) 4179(3) 5279(3) 31(1) C(65) -682(3) 2832(3) 6060(3) 25(1) C(66) -725(4) 3653(3) 5979(3) 29(1) C(67) -635(4) 3828(3) 6677(3) 34(1) C(68) -544(4) 3124(3) 7166(3) 27(1) C(69) -414(4) 3021(3) 7913(3) 33(1) C(70) -333(4) 2333(3) 8389(3) 28(1) C(71) -253(4) 2224(3) 9175(3) 33(1) C(72) -249(4) 1447(3) 9413(3) 30(1) C(73) -307(3) 1090(3) 8764(3) 27(1) C(74) 3201(14) 3322(10) 168(10) 61(6) 0.5 C(75) 4245(14) 3814(11) -103(11) 92(4) 0.5 967(4) 48(2) C(48) 6601(6) 4071(4) 1333(5) 92(3) C(49) 6238(4) 1630(4) 2179(4) 60(2) C(50) 6059(6) 1428(5) 1432(5) 90(3) C(51) -4578(4) 1380(3) 7322(3) 36(1) C(52) -4803(5) 535(4) 7450(4) 64(2) C(53) -4290(4) 1691(3) 8998(3) 38(1) C(54) 384(6 69(2) C(55) 3170(4) 3212(3) 1648(3) 34(1) C(56) 2778(5) 3382(3) 970(3) 42(1) C(57)  - 171 - Table 3.6. Atomic coordinate ic displacement parameters (A^2 x 10^3) for 221. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor. (continued) y z U(eq)  occ s ( x 10^4) and equivalent isotrop x C(76) 1099(5) 4012(4)     699(3) 57(2) C(77) 1176(6) 4882(4) 75(2) -201(5) 2854(3) 47(2) C(79) -1180(5) 3037(3) 10217(3) 52(2) -237(4) 1021(3) 04(3) 37(1) -1264(4) 765(4) 14(3) 47(2) C(82) 2344(5) 1558(5) 8518(5) 79(2) C(84) 1819(8) 4248(6) 7402(8) 139(5) N(1) 2978(3) 4449(2) 3081(2) 24(1) N(2) 2997(3) 3282(2) 4328(2) 22(1) N(3) 956(3) 56(2) ) 22(1) -516(3) 2) (2) 21(1) N(5) 4118(3) 3054(2) 2938(2) 24(1) N(6) 2328(3) 2316(2) 3510(2) 19(1) N(7) -563(3) (2) (2) 17(1) N(8) -1942(3) 1526(2) 7495(2) 22(1) N(9) 2498(3) 3387(2) 2275(2) 26(1) 0) 1326(3) 3724(2) 3719(2) 22(1) N(11) -575(3) 2512(2) 6753(2) 25(1) -359(3) 1610(2) 8151(2) 24(1) Co(1) 2707(1) 3368(1) 3313(1) 21(1) Co(2) -496(1) 1418(1) 7143(1) 19(1) 2698(2) 2481(2) 8415(2) 113(1) 2868(3) 941(2) 9144(3) 200(2) C(83) 4161(8) 6792(6) 5660(5) 70(3) 0.75(1) (3) (2) 876(2) 107(1) 0.75(1) (4) ) 156(2) 0.75(1) Cl(5) 1162(3) 4613(2) 8274(2) 144(1) ) 4257(4) 440(4) 154(4) 0.61(1) 2690(6) 4939(6) 6903(7) 152(5) 0.39(1) C(20B) 3230(60) 6350(60) 1860(60) 49(3) 0.5 6036(8) 55(4) 0.5 3868(10) 92(4) 0.5 C(74B) 3501(12) 3207(8) 176(8) 40(4) 0.5 9) 8430(12) 416(15) 256(11) 0.25(1)  6932(12) 233(12) 0.25(1) C(83B) 4330(20) 7440(15) 5610(40) 190(30) 0.25(1)  473(5) C(78) 9662(3) C(80) 102 C(81) 106 13 6857(2 N(4) 309( 7482 1192 6128 N(1 N(12) Cl(1) Cl(2) Cl(3) 3933 Cl(4) 3104 5823 5 7338(3 5392(3) Cl(6A) 3104(5 7 Cl(6B) C(21B) 3363(12) 949(8) C(75B) 3759(15) -318(11) Cl(4B) 4023(1 5 Cl(3B) 3280(20) 5727(16)  - 172 - Table 3.7. Crystal data for 222. Empirical Formula C81H90N12Co2 Formula Weight 1349.51 Crystal Colour, Habit Red, p Crysta 0.12 X 0.27 X 0.54 Crystal System Trigon Space Group P 63/m a/Å 15.0431(8) b/Å 15.0431(8) c/Å 24.400(2) α/ 90.0 β/ 90.0 γ/ 120.0    Lattic eters V 4781.8 Z Val 2 Dcalc 0.937 F000 1428.00 µ(M -1 3.87 Temp  /K 173 T 45184 No. o tions Meas U 3875 ( 15) No. Observations (I>0.0 3875 No. Variables 158 R1; w ined on F2, 0.0408 Good Fit Indicato 1.087 No. o I> 3252 R1; w ined on F, I (0.0332; 0.0880) rism l Dimensions al   (#176) deg deg deg e Param /Å3 (6) ue /g cm-3  oKα) /cm erature otal: f Reflec ure nique: Rint = 0.03 0σ(I)) R2 (ref all data) ; 0.0906 ness of r (GOF) f Observations ( 2σ(I)) R2 (ref >2σ(I))   - 173 - Table 3.8. Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 222. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.  x y z U(eq) C(1) 5878(1) 4024(1) 4912(1) 26(1) C(2) 5968(1) 4911(1) 4651(1) 30(1) C(3) 6623(1) 5735(1) 4969(1) 29(1) C(4) 6935(1) 5328(1) 5419(1) 24(1) C(5) 7618(1) 5868(1) 5832(1) 26(1) C(6) 7965(1) 5478(1) 6244(1) 23(1) C(7) 8663(1) 6029(1) 6674(1) 26(1) C(8) 8782(1) 5333(1) 6985(1) 23(1) C(9) 8151(1) 4365(1) 6737(1) 21(1) C(10) 9408(1) 5516(1) 7500 25(1) C(11 C(12A) C(11B) C(12B)  A) 5458(1) 4904(1) 4119(1) 40(1) 5967(2) 4695(3) 3634(1) 64(1) C(13) 6952(1) 6845(1) 4883(1) 42(1) C(14) 7857(1) 7392(1) 4496(1) 69(1) N(1) 6452(1) 4260(1) 5366(1) 22(1) N(2) 7658(1) 4441(1) 6295(1) 19(1) Co(1) 6667 3333 5832(1) 18(1) 5458(1) 4904(1) 4119(1) 40(1) 4904(7) 3987(6) 3832(3) 73(3)   - 174 - Table 3.9. Crystal data for 223. Empirical Formula C84H96.5Cl6.5N12Fe2 Formula Weight 1616.36 Crys r, Habit Black, c Crys 0.20 X 0.25 X 0.50 Cryst  Triclini Space Group P-1 (# a/Å 13.3137(10) b/Å 17.3134(14) c/Å 18.8476(15) α/ 88.243 β/deg 72.590(4) γ/ 80.864    Lattic eters V/ 4092.2 Z Valu 2 Dcalc/ 1.312 F000 1687.0 µ(Mo -1 6.18 Temp  /K 173 T 81561 No. o tions Mea U 19584 356) No. Observations (I>0.00 19584 No. Variables 1013 R1; w ined on F2, 0.0853 Good  Fit Indicato 1.044 No. o I> 14380 R1; w ined on F, 0.0545 tal Colou olumn tal Dimensions al System c  2) deg (4) deg (4) e Param Å3 (6) e g cm-3 0 Kα) /cm erature otal: f Reflec sure nique:  (Rint = 0.0 σ(I)) R2 (ref all data) ; 0.1570 ness of r (GOF) f Observations ( 2σ(I)) R2 (ref I>2σ(I)) ; 0.1338   - 175 - Table 3.10. Atomic coordina ic displacement parameters (A^2 x 10^3) for 223. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.  y z U(eq)  occ tes ( x 10^4) and equivalent isotrop x C(1) 5917(3) 3444(2) 1577(2) 33(1) C(2) 4974(3) 3613(2) 1363(2) 37(1) 4162(3) 3828(2) 2005(2) 34(1) C(4) 4642(2) 3782(2) 2595(2) 27(1) 4139(2) 3939(2) 3338(2) 28(1) 4596(2) 3927(2) 3909(2) 24(1) C(7) 4064(2) 4090(2) 4672(2) 26(1) C(8) 4824(2) 4035(1) 5036(2) 23(1) C(9) 5812(2) 3826(1) 4482(1) 21(1) C(10) 4657(2) 4211(1) 5843(2) 25(1) C(11) 5283(2) 2796(1) 6189(1) 20(1) 5250(2) 3616(1) 6225(2) 22(1) C(13) 5817(2) 3729(2) 6699(2) 26(1) C(14) 6180(2) 2983(1) 6950(2) 23(1) C(15) 6766(2) 2818(2) 7439(2) 25(1) C(16) 7102(2) 2093(2) 7687(2) 23(1) C(17) 7653(2) 1928(2) 8234(2) 27(1) 8) 7780(2) 1130(2) 8321(2) 26(1) C(19) 7314(2) 829(2) 7828(2) 23(1)  4790(20) 3530(20) 614(5) 47(4) 0.51(1) C(21A) 5798(7) 3343(8) 6(5) 72(4) 0.51(1) C(20B) 5040(20) 3590(20) 548(5) 59(6) 0.49(1) 5477(13) 4223(9) 85(6) 106(6) 0.49(1) 3008(3) 4088(2) 2087(2) 49(1) C(23) 2728(4) 4964(3) 2016(4) 86(2) (3) (2) 8596(2) 40(1) (4) ) 72(1) C(26) 8230(3) 651(2) 8865(2) 35(1) ) 499(3) 9559(3) 79(2) 6572(2) 5012(2) 2318(2) 27(1) C(29) 7028(2) 5709(2) 2210(2) 28(1) 5590(2)   31(1) 4820(2) 2833(2) 26(1) C(32) 8526(2) 4443(2) 3203(2) 28(1) ) 3686(2) 3478(2) 25(1) 3301(2) 28(1) C(35) 8973(2) 2564(2) 4031(2) 24(1) C(36) 8139(2) 2516(2) 3726(2) 23(1) C(3) C(5) C(6) C(12) C(1 C(20A) 1 C(21B) C(22) C(24) 8065 C(25) 9163 2517 2665(3 8144(3) C(27) 7385(4 C(28) C(30) 7831(2) 2533(2) C(31) 7853(2) C(33) 8550(2 C(34) 9230(2) 3876(2)  - 176 - Table 3.10. Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (continued) (A^2 x 10^3) for 223. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor. x y U(eq)  occ z C(37) 9495(2) 1909(2) 4408(2) 28(1) C(38) 7851(2) 1748(1) 5537(2) 21(1) C(39) 8753(2) 1451(2) 4949(2) 21(1) C(40) 8848(2) 650(2) 5002(2) 22(1) C(41) 8023(2) 474(1) 5624(1) 19(1) C(42) 7853(2) -259(1) 5916(2) 20(1) C(43) 7051(2) -428(1) 6524(1) 18(1) C(44) 6884(2) -1176(1) 6847(2) 21(1) C(45) 5961(2) -1050(1) 7429(1) 21(1) C(46) 5585(2) -232(1) 7446(1) 20(1) C(47) 6657(3) 6423(2) 1 - - -1 9  3 8857(2) 2327(2) 875(2) 32(1) C(58) 8133(2) 231 ) C(59) 7690(2) 1680(2) 1954(2) 27(1) C(60) 6943(2) 1669(1) 2639(2) 21(1) C(61) 6498(2) 1016(2) 2998(2) 24(1) C(62) 5740(2) 1279(1) 3644(1) 19(1) C(63) 5743(2) 2095(1) 3676(1) 20(1) C(64) 5000(2) 824(1) 4187(1) 21(1) C(65) 5665(2) 1017(1) 5325(1) 19(1) C(66) 4848(2) 1002(1) 4988(1) 19(1) C(67) 3909(2) 1131(2) 5558(2) 22(1) C(68) 4171(2) 1214(1) 6227(1) 19(1) C(69) 3477(2) 1331(1) 6935(2) 21(1) C(70) 3720(2) 1423(1) 7585(1) 20(1) C(71) 3003(2) 1511(2) 8319(2) 23(1) C(72) 3602(2) 1585(2) 8789(2) 25(1) C(73) 4668(2) 1542(2) 8328(1) 23(1) C(74A) 9806(4) 3414(3) 96(2) 73(2) 0.87(1) 824(2) 38(1) C(48) 6136(5) 6259(2) 1258(3) 75(2) C(49) 8530(3) 6169(2) 2604(2) 45(1) C(50) 8029(4) 6693(2) 3287(3) 73(1) C(51) 7577(2) 1948(2) 6585(2) 28(1) C(52) 7377(3) 2311(2) 5926(2) 48(1) C(53) 5424(2) 641(2) 7943(2) 28(1) C(54) 4542(3) -1290(2) 8623(2) 37(1) C(55) 8493(3) 3503(2) 1435(2) 37(1) C(56) 090(3) 077(2) 774(2) 42(1) C(57) 3(2) 1605(2) 26(1  - 177 - Table 3.10. Atomic coordina ic displacement parameters (A^2 x 10^3) for 223. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.  y z U(eq)  occ tes ( x 10^4) and equivalent isotrop x C(75A) 9219(8) 4096(4) -219(4) 151(5) 0.87(1) C(74B) 9806(4) 3414(3) 73(2) 0.13(1) 10560(30) 3890(20) 82(11) 0.13(1) C(76) 9284(2) 1630(2) 355(2) 36(1) 10153(3) 1069(2) ) 44(1) 1827(2) 1501(2) 8524(2) 31(1) C(79) 1562(3) 676(2) 8555(2) 42(1) C(80) 3222(3) 1696(2) 9617(2) 39(1) C(81) 4053(4) 1487(4) 9995(2) 77(2) N(1) 5739(2) 3544(1) 2303(1) 25(1) N(2) 5689(2) 3757(1) 3808(1) 20(1) 5828(2) 2414(1) 6615(1) 19(1) N(4) 6907(2) 1395(1) 7447(1) 20(1) N(5) 7057(2) 4477(1) 2679(1) 24(1) N(6) 7873(2) 3183(1) 3396(1) 21(1) N(7) 7398(2) 1172(1) 5943(1) 18(1) N(8) 6222(2) 145(1) 6924(1) 18(1) 9) 7911(2) 3056(1) 1936(1) 26(1) N(10) 6459(2) 2332(1) 3082(1) 19(1) 5277(2) 1141(1) 6058(1) 17(1) N(12) 4754(2) 1438(1) 7612(1) 19(1) Fe(1) 6789(1) 3397(1) 2872(1) 20(1) 6070(1) 1282(1) 6765(1) 15(1) 518(3) 2289(3) 2116(3) 68(1) Cl(1) 1664(3) 2474(4) 1469(2) 134(2) 0.70(1) (5) (2) 95(2) 0.70(1) (18) ) 222(10) 0.30(1) Cl(2B) 1260(20) 1434(11) 2082(16) 193(10) 0.30(1)    8892(2) 3446(2) 53(1) -411(2) 9656(1) 3036(1) 119(1) Cl(4) -707(1) 8331(1) 3985(1) 87(1) 4378(4) ) 124(3) 5242(2) 5780(2) 215(2) Cl(6) 9227(3) 3587(2) 5947(2) 178(1) ) 5084(7) -1224(6) 94(4) 0.13(1)  4566(10) ) 162(9) 0.13(1) C(85) 8419(18) 5340(12) -490(15) 71(9) 0.13(1)  96(2) C(75B) 290(20) C(77) 552(2 C(78) N(3) N( N(11) Fe(2) C(82) Cl(2) 641 Cl(1B) 1333 1304 2394(2) 2937(19 1610(13) C(83) 205(3) Cl(3) C(84) 8473(6) 5648(4 Cl(5) 8785(2) Cl(7) 9558(8 Cl(8) 7734(12) -187(10  - 178 - Table 3.11. Crystal data for 224. Empirical Formula C81H90N12Fe2 Formula Weight 1343.35 Crystal Colour, Habit Black, Crysta 0.20 X 0.44 X 0.54 Crystal System Trigon Space Group P 63/m a/Å 15.0249(11) b/Å 15.0249(11) c/Å 24.422(2) α/d 90.0 β/ 90.0 γ/ 120.0    Lattic eters V 4774.6 Z Val 2 Dcalc/ 1.112 F000 1676.0 µ(Mo -1 5.16 Temp  /K 173 T 60586 No. o tions Meas U 3788 ( 05) No. Observations (I>0.00 3788 No. Variables 157 R1; w ined on F2, 0.0517 Good Fit Indicato 1.167 No. o I> 3024 R1; w ined on F, I 0.0379  prism l Dimensions al   (#176) eg deg deg e Param /Å3 (6) ue g cm-3 0 Kα) /cm erature otal: f Reflec ure nique: Rint = 0.05 σ(I)) R2 (ref all data) ; 0.1148 ness of r (GOF) f Observations ( 2σ(I)) R2 (ref >2σ(I)) ; 0.1066   - 179 - Table 3.12. Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 224. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor. U(eq)  x y z C(1) 5947(1) 1837(1) 4912(1) 29(1) C(2) 5059(1) 1041(1) 4653(1) 32(1) C(3)  4240(1) 875(1) 4972(1) 32(1) C(4) 4649(1) 1592(1) 5419(1) C C(21A) C(20B) C Fe(1) 6667 33 )   26(1) C(5) 4115(1) 1732(1) 5835(1) 28(1) C(6) 4501(1) 2465(1) 6249(1) 25(1) C(7) 3946(1) 2605(1) 6677(1) 28(1) C(8) 4637(1) 3423(1) 6988(1) 24(1) C(9) 5606(1) 3769(1) 6740(1) 23(1) C(10) 4451(2) 3863(2) 7500 28(1) C(16) 2583(2) 444(2) 4499(1) 75(1) (20A) 5057(2) 532(1) 4123(1) 43(1) 5270(3) 1249(2) 3642(1) 71(1) 5057(2) 532(1) 4123(1) 43(1) (21B) 6027(5) 894(6) 3836(3) 71(2) C(22) 3132(1) 94(1) 4887(1) 46(1) N(1) 5717(1) 2179(1) 5365(1) 25(1) N(2) 5536(1) 3201(1) 6299(1) 21(1) 33 5833(1) 20(1  - 180 - Table 3.13. Crystal data for 261. Empirical Formula C101H80N12Fe2Cl6 Formula Weight 1786.17 Crystal Colour, Habit Green, hexagon   Crystal Dimensions 0.10 X 0.20 X 0.35 Crystal System Monoclinic Space Group C 2/c (#15) a/Å 28.2832(19) b/Å 12.7319(8) c/Å 24.0914(14) α/deg 90.0 β/deg 95.252(3) γ/deg 90.0    Lattice Parameters V/Å3 8638.9(9) Z Value 4 Dcalc/g cm-3 1.373 F000 3696.00 µ(MoKα) /cm-1 5.79 Temperature /K 173 Total: 53355 No. of Reflections Measure Unique: 7772 (Rint = 0.034) No. Observations (I>0.00σ(I)) 7772 No. Variables 516 R1; wR2 (refined on F2, all data) 0.058; 0.127 Goodness of Fit Indicator (GOF) 1.10 No. of Observations (I>2σ(I)) 6148 R1; wR2 (refined on F, I>2σ(I)) 0.046; 0.119   - 181 - Table 3.14. Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 261. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.  x y z U(eq) C(1) 2034(1) 585(2) 6685(1) 36(1) C(2) 2253(1) -358(2) 6547(1) 39(1) C(3)  2072(1) -1129(2) 6851(1) 32(1) C(4) 1737(1) -649(2) 7181(1) 26(1) C(5) 1462(1) -1145(2) 7552(1) 28(1) C(6) 1139(1) -640(2) 7873(1) 26(1) C(7) 814(1) -1131(2) 8206(1) 31(1) C(8) 540(1) -365(2) 8415(1) 29(1) C(9) 701(1) 590(2) 8199(1) 30(1) C(10) 148(1) -497(2) 8805(1) 37(1) C(11) 508(1) 451(2) 6815(1) 31(1) C(12) 224(1) 354(2) 6307(1) 31(1) C(13) 386(1) 1104(2) 5962(1) 32(1) C(14) 770(1) 1644(2) 6268(1) 28(1) C(15) 1054(1) 2439(2) 6082(1) 29(1) C(16) 1450(1) 2870(2) 6394(1) 29(1) C(17) 1769(1) 3649(2) 6222(1) 37(1) C(18) 2114(1) 3793(2) 6652(1) 39(1) C(19) 2002(1) 3129(2) 7083(1) 33(1) C(20) -101(1) -1578(2) 8701(1) 53(1) C(21) 369(1) -445(3) 9406(1) 63(1) C(22) 1506(1) -2309(2) 7605(1) 36(1) C(23) 1385(1) -2964(2) 7149(1) 45(1) C(24) 1427(1) -4050(3) 7214(2) 66(1) C(25) 1580(1) -4480(3) 7717(2) 76(1) C(26) 1699(1) -3849(3) 8162(2) 74(1) C(27) 1669(1) -2748(2) 8113(1) 52(1) C(28) 934(1) 2857(2) 5507(1) 37(1) C(29) 515(1) 3375(2) 5369(1) 55(1) C(30) 418(2) 3784(3) 4820(2) 78(1) C(31) 747(2) 3651(3) 4441(1) 76(1) C(32) 1155(2) 3128(3) 4573(1) 73(1) C(33) 1255(1) 2739(2) 5103(1) 51(1) C(34) 2258(1) 1256(2) 8093(1) 30(1) C(35) 2484(1) 1426(2) 8630(1) 32(1) C(36) 2174(1) 2000(2) 8913(1) 32(1) C(37) 1762(1) 2186(2) 8539(1) 27(1) C(38) 1365(1) 2798(2) 8636(1) 28(1)  - 182 - Table 3.14. Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 261. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor. (continued) x y z U(eq) c  oc C(39) 1003(1) 3065(2) 8227(1) 28(1) C(40) 647(1) 3848(2) 8246(1) 31(1) C(41) 405(1) 3922(2) 7724(1) 29(1) C(42) 613(1) 3151(2) 7400(1) 29(1) Fe(1) 1338(1) 1502(1) 7401(1) 24(1)  C(43) 0 4638(3) 7500 32(1) C(44) -159(1) 5336(2) 7967(1) 45(1) C(45) 1316(1) 3180(2) 9215(1) 32(1) C(46) 938(1) 2838(3) 9484(1) 64(1) C(47) 894(2) 3143(4) 10035(2) 86(1) C(48) 1220(1) 3806(3) 10305(1) 66(1) C(49) 1564(1) 4221(3) 10017(1) 65(1) C(50) 1619(1) 3905(3) 9475(1) 53(1) N(1) 1725(1) 427(2) 7067(1) 28(1) N(2) 1060(1) 440(2) 7876(1) 26(1) N(3) 834(1) 1201(2) 6801(1) 26(1) N(4) 1610(1) 2568(2) 6937(1) 27(1) N(5) 1830(1) 1710(2) 8030(1) 29(1) N(6) 965(1) 2635(2) 7690(1) 26(1)  - 183 - Table 3.15. Crystal data for 262 Empirical Formula C101H82N12Co2Cl4 Formula Weight 1723.45 Crystal Colour, Habit red, plate Crystal Dimensions 0.10 X 0.40 X 0.55 Crystal System Monoclinic Space Group C 2/c (#15) a/Å 28.2196(9) b/Å 12.5132(4) c/Å 23.8825(7) α/deg 90.0 β/deg 96.244(2) γ/deg 90.0    Lattice Parameters V/Å3 8383.3(5) Z Value 4 Dcalc/g cm-3 1.366 F000 3576.00 µ(MoKα) /cm-1 5.81 Temperature /K 173 Total: 61786 No. of Reflections Measure Unique: 10170 (Rint = 0.053) No. Observations (I>0.00σ(I)) 10170 No. Variables 540 R1; wR2 (refined on F2, all data) 0.072; 0.113 Goodness of Fit Indicator (GOF) 1.00 No. of Observations (I>2σ(I)) 7448 R1; wR2 (refined on F, I>2σ(I)) 0.043; 0.098   - 184 - Table 3.16. Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 262. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.  x y z U(eq) C(1) 2008(1) 3064(2) 2136(1) 18(1) C(2) 2122(1) 3743(2) 1703(1) 21(1) C(3)  1768(1) 3625(2) 1266(1) 18(1) C(4) 1445(1) 2847(2) 1438(1) 15(1) C(5) 1050(1) 2407(2) 1110(1) 15(1) C(6) 765(1) 1597(2) 1287(1) 15(1) C(7) 382(1) 1048(2) 971(1) 17(1) C(8) 220(1) 277(2) 1309(1) 16(1) C(9) 504(1) 375(2) 1835(1) 16(1) C(10) -151(1) -589(2) 1189(1) 19(1) C(11) -699(1) 531(2) 1790(1) 16(1) C(12) -550(1) -438(2) 1559(1) 15(1) C(13) -845(1) -1214(2) 1741(1) 17(1) C(14) -1162(1) -705(2) 2081(1) 15(1) C(15) 1477(1) -1220(2) 2592(1) 16(1) C(16) 1722(1) -728(2) 2191(1) 15(1) C(17) 2018(1) -1228(2) 1821(1) 18(1) C(18) 2164(1) -449(2) 1481(1) 22(1) C(19) 1965(1) 519(2) 1649(1) 21(1) C(20) -350(1) -566(2) 569(1) 29(1) C(21) 95(1) -1682(2) 1314(1) 27(1) C(22) 942(1) 2833(2) 526(1) 18(1) C(23) 1276(1) 2722(2) 140(1) 23(1) C(24) 1189(1) 3154(2) -396(1) 30(1) C(25) 773(1) 3693(2) -552(1) 34(1) C(26) 435(1) 3801(2) -179(1) 34(1) C(27) 518(1) 3368(2) 362(1) 25(1) C(28) 1538(1) -2400(2) 2673(1) 20(1) C(29) 1738(1) -2793(2) 3188(1) 28(1) C(30) 1791(1) -3887(2) 3271(1) 39(1) C(31) 1649(1) -4591(2) 2842(2) 43(1) C(32) 1452(1) -4211(2) 2328(1) 39(1) C(33) 1395(1) -3117(2) 2237(1) 28(1) C(34) 2255(1) 1171(2) 3100(1) 18(1) C(35) 2489(1) 1325(2) 3646(1) 19(1) C(36) 2185(1) 1906(2) 3939(1) 18(1) C(37) 1770(1) 2117(2) 3564(1) 15(1) C(38) 1375(1) 2750(2) 3658(1) 15(1)  - 185 - Table 3.16. Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 262. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor. (continued) x y z U(eq) C(39) 1009(1) 3015(2) 3245(1) 15(1) C(40) 653(1) 3827(2) 3262(1) 16(1) C(41) 407(1) 3891(2) 2735(1) 14(1) C(42) 606(1) 3087(2) 2411(1) 15(1) C(43) 0 4611(2) 2500 17(1) C(44) -159(1) 5324(2) 2968(1) 25(1) C(45) 1345(1) 3181(2) 4238(1) 16(1) C(46) 960(1) 2897(2) 4523(1) 23(1) C(47) 931(1) 3261(2) 5068(1) 30(1) C(48) 1283(1) 3925(2) 5327(1) 30(1) C(49) 1661(1) 4220(2) 5046(1) 27(1) C(50) 1695(1) 3851(2) 4504(1) 21(1) N(1) 1606(1) 2521(1) 1983(1) 14(1) N(2)   829(1) 1145(1)   1828(1) 14(1) N(3) -1061(1) 382(1) 2104(1) 14(1) N(4) 1701(1) 367(1) 2073(1) 15(1) N(5) 1825(1) 1638(1) 3046(1) 15(1) N(6) 962(1) 2569(1) 2706(1) 14(1) Cl(1) 2779(1) 3808(1) 443(1) 55(1) Cl(2) 3379(1) 5352(1) -47(1) 64(1) Co(1) 1332(1) 1442(1) 2424(1) 13(1) C(51) 3291(1) 4613(2) 554(1) 43(1)   - 186 - Table 3.17. Crystal data for 263 Empirical Formula C100H80N12Mn2Cl2 Formula Weight 1630.54 Crystal Colour, Habit red, plate Crystal Dimensions 0.03 X 0.25 X 0.60 Crystal System Monoclinic Space Group C 2/c (#15) a/Å 30.649(5) b/Å 11.690(2) c/Å 25.147(3) α/deg 90.0 β/deg 109.172(5) γ/deg 90.0    Lattice Parameters V/Å3 8510(2) Z Value 4 Dcalc/g cm-3 1.273 F000 3392.00 µ(MoKα) /cm-1 4.15 Temperature /K 173 Total: 33266 No. of Reflections Measure Unique: 6927 (Rint = 0.058) No. Observations (I>0.00σ(I)) 6927 No. Variables 563 R1; wR2 (refined on F2, all data) 0.105; 0.149 Goodness of Fit Indicator (GOF) 1.11 No. of Observations (I>2σ(I)) 5125 R1; wR2 (refined on F, I>2σ(I)) 0.064; 0.132   - 187 - Table 3.18. Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 263. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.  x y z U(eq)  occ C(1) 1502(2) 7644(4) 1494(2) 25(1) C(2) 1429(2) 6939(5) 1023(2) 28(1) C(3)  969(2) 7056(5) 711(2) 26(1) C(4) 769(2) 7850(4) 985(2) 20(1) C(5) 307(2) 8257(4) 786(2) 21(1) C(6) 126(2) 9160(4) 1008(2) 20(1) C(7) -327(2) 9639(4) 802(2) 19(1) C(8) -340(2) 10530(4) 1144(2) 17(1) C(9) 106(2) 10551(4) 1567(2) 20(1) C(10) -730(2) 11371(4) 1100(2) 21(1) C(11) 824(2) 10325(4) 3018(2) 20(1) C(12) 874(2) 11288(4) 3374(2) 18(1) C(13) 1109(2) 12076(5) 3173(2) 23(1) C(14) 1198(2) 11601(4) 2699(2) 19(1) C(15) 1428(2) 12111(4) 2376(2) 22(1) C(16) 1516(2) 11624(4) 1907(2) 19(1) C(17) 1758(2) 12132(5) 1573(2) 24(1) C(18) 1744(2) 11358(5) 1159(2) 25(1) C(19) 1503(2) 10398(5) 1243(2) 22(1) C(20) -1152(2) 11103(5) 583(2) 26(1) C(21) -561(2) 12589(4) 1042(2) 27(1) C(22) -21(2) 7644(4) 293(2) 18(1) C(23) -236(2) 8156(5) -222(2) 27(1) C(24) -547(2) 7569(5) -660(2) 30(1) C(25) -655(2) 6443(5) -583(2) 35(2) C(26) -448(2) 5920(5) -80(2) 39(2) C(27) -129(2) 6500(5) 361(2) 30(1) C(28) 1602(2) 13308(5) 2526(2) 28(1) C(29) 2002(2) 13501(5) 2971(3) 43(2) C(30) 2153(3) 14622(7) 3110(4) 66(2) C(31) 1903(3) 15519(6) 2817(4)  64(2) C(32) 1501(3) 15334(5) 2384(3) 57(2) C(33) 1349(2) 14219(5) 2237(3) 41(2) C(34) 2166(2) 9638(4) 2728(2) 27(1) C(35) 2466(2) 9711(5) 3287(2) 35(2) C(36) 2268(2) 9102(5) 3609(2) 29(1) C(37) 1848(2) 8638(4) 3236(2) 22(1) C(38) 1521(2) 7966(4) 3366(2) 22(1)  - 188 - Table 3.18. Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 263. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor. (continued) x y z U(eq) C(39) 1092(2) 7626(4) 2989(2) 20(1) C(40) 805(2) 6756(4) 3085(2) 19(1) C(41) 418(2) 6664(4) 2613(2) 22(1) C(42) 477(2) 7508(4) 2244(2) 20(1) C(43) 0 5890(6) 2500   23(2) 1/2 C(44) -47(2) 5126(4) 1989(2) 34(2) C(45) 1634(2) 7536(5) 3958(2) 26(1) C(46) 1326(2) 7757(5) 4249(2) 27(1) C(47) 1410(2) 7325(5) 4784(2) 36(2) C(48) 1787(2) 6643(6) 5026(2) 43(2) C(49) 2099(2) 6417(6) 4745(3) 48(2) C(50) 2020(2) 6868(5) 4210(2) 35(2) C(51A) 2122(14) 3710(60) 5131(12) 250(20) 1/4 C(51B) 2490(30) 2520(30) 4720(30) 150(17) 1/4 N(1) 1116(1) 8201(4) 1472(2) 19(1) N(2) 385(1) 9763(3) 1488(2) 18(1) N(3) 1018(1) 10486(3) 2621(2) 18(1) N(4) 1367(1) 10534(4) 1693(2) 20(1) N(5) 1790(1) 9009(4) 2684(2) 20(1) N(6) 877(1) 8068(4) 2456(2) 19(1) Mn(1) 1090(1) 9328(1) 2060(1) 18(1)   Cl(1) 2741(4) 3688(13) 4465(4) 127(5) 1/4 Cl(2) 2304(11) 3120(20) 5242(14) 265(14) 1/4 Cl(3) 2632(5) 3321(12) 5684(11) 180(9) 1/4 Cl(4) 2262(7) 3316(15) 4543(9) 176(8) 1/4   - 189 - Table 3.19. Crystal data for 264 Empirical Formula C99H78N12Ga2 Formula Weight 1575.17 Crystal Colour, Habit red, plate Crystal Dimensions 0.10 X 0.25 X 0.30 Crystal System Monoclinic Space Group C 2/c (#15) a/Å 28.1300(7) b/Å 12.8500(3) c/Å 24.1340(5) α/deg 90.0 β/deg 94.951(1) γ/deg 90.0    Lattice Parameters V/Å3 8691.2(3) Z Value 4 Dcalc/g cm-3 1.204 F000 3272.00 µ(MoKα) /cm-1 6.73 Temperature /K 173 Total: 62051 No. of Reflections Measure Unique: 8504 (Rint = 0.042) No. Observations (I>0.00σ(I)) 8504 No. Variables 548 R1; wR2 (refined on F2, all data) 0.061; 0.114 Goodness of Fit Indicator (GOF) 1.11 No. of Observations (I>2σ(I)) 6463 R1; wR2 (refined on F, I>2σ(I)) 0.042; 0.106   - 190 - Table 3.20. Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 264. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.  x y z U(eq)  occ C(1) 2027(1) 3128(2) 2024(1) 30(1) C(2) 2119(1) 3786(2) 1591(1) 35(1) C(3)  1763(1) 3629(2) 1180(1) 36(1) C(4) 1458(1) 2849(2) 1363(1) 26(1) C(5)   1050(1) 2408(2) 1069(1) 26(1) C(6) 766(1) 1625(2) 1259(1) 25(1) C(7) 384(1) 1076(2) 956(1) 30(1) C(8) 223(1) 330(2) 1296(1) 29(1) C(9) 504(1) 448(2) 1807(1) 28(1) C(10) -139(1) -529(2) 1192(1) 35(1) C(11) -713(1) 534(2) 1783(1) 25(1) C(12) -534(1) -408(2) 1583(1) 26(1) C(13) -802(1) -1175(2) 1804(1) 27(1) C(14) -1135(1) -691(2) 2128(1) 23(1) C(15) -1463(1) -1190(2) 2450(1) 24(1) C(16) -1757(1) -708(2) 2808(1) 22(1) C(17) -2094(1) -1199(2) 3131(1) 27(1) C(18) -2299(1) -440(2) 3418(1) 32(1) C(19) -2095(1) 507(2) 3272(1) 29(1) C(20) -361(1) -490(3) 591(1) 59(1) C(21) 113(1) -1587(2) 1297(1) 50(1) C(22) 925(1) 2831(2) 494(1) 38(1) C(23) 1245(1)   2718(2) 85(1) 52(1) C(24) 1140(2) 3110(3) -437(1) 74(1) C(25) 742(2) 3616(3) -562(2) 75(1) C(26) 404(2) 3761(3) -179(2) 78(1) C(27) 503(1) 3344(2) 367(1) 58(1) C(28) -1493(1) -2346(2) 2405(1) 29(1) C(29) -1636(1) -2812(2) 1904(1) 40(1) C(30) -1664(1) -3895(2) 1865(1) 51(1) C(31) -1564(1) -4505(2) 2323(2) 51(1) C(32) -1423(1) -4046(2) 2827(2) 47(1) C(33) -1388(1) -2978(2) 2875(1) 34(1) C(34) 2284(1) 1316(2) 3157(1) 25(1) C(35) 2483(1) 1469(2) 3704(1) 28(1) C(36) 2165(1) 2049(2) 3967(1) 27(1) C(37) 1768(1) 2255(2) 3573(1) 24(1)  - 191 - Table 3.20. Atomic coordinates ( x 10^4) and equivalent isotropic displacement parameters (A^2 x 10^3) for 264. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor. (continued) x y z U(eq)  occ C(38) 1362(1) 2854(2) 3649(1) 23(1) C(39) 1001(1) 3107(2) 3241(1) 24(1) C(40) 641(1) 3890(2) 3254(1) 26(1) C(41) 404(1) 3945 (2) 2733(1) 26(1) C(42) 612(1) 3165(2) 2422(1) 24(1) C(43) 0 4644(3) 2500 30(1) C(44) -169(1) 5338(2) 2962(1) 43(1) C(45) 1299(2) 3263(3) 4216(1) 25(1) 0.805(6) C(46) 918(1) 2901(3) 4493(1) 43(1) 0.805(6) C(47) 872(2) 3203(4) 5036(2) 59(1) 0.805(6) C(48) 1192(2) 3879(4) 5305(2) 51(1) 0.805(6) C(49) 1558(2) 4250(4) 5036(2) 41(1) 0.805(6) C(50) 1616(2) 3948(3) 4492(2) 31(1) 0.805(6) N(1) 1632(1) 2558(2) 1897(1) 24(1) N(2) 828(1) 1196(2) 1792(1) 24(1) N(3) -1069(1) 381(2) 2109(1) 23(1) N(4) -1770(1) 361(2) 2909(1) 23(1) N(5) 1859(1) 1787(2) 3068(1) 25(1) N(6) 966(1) 2669(2) 2712(1) 23(1) Ga(1) 1363(1) 1493(1) 2411(1) 21(1) C(45B) 1333(6) 3094(9) 4267(4) 25(1) 0.195(6) C(46B) 1225(5) 2354(7) 4657(4) 35(4) 0.195(6) C(47B) 1184(5) 2646(9) 5205(4) 50(5) 0.195(6) C(48B) 1252(7) 3679(10) 5364(4) 51(1) 0.195(6) C(49B) 1361(7) 4419(7) 4974(6) 45(5) 0.195(6) C(50B) 1401(6) 4127(8) 4426(5) 34(4) 0.195(6)   - 192 - 3.4 NMR Spectra of Selected Compounds  Figure 3.1. 1H NMR spectrum of 155 in d6-DMSO at 25 oC (300 MHz).   Figure 3.2. 13C APT NMR spectrum of 155 in d6-DMSO at 25 oC (75 MHz).  - 193 -  Figure 3.3. 1H NMR spectrum of 159-H2·2HBr in CDCl3/CD3OD at 25 oC (300 MHz).   Figure 3.4. 13C APT NMR spectrum of 159-H2·2HBr in CDCl3/CD3OD at 25 oC (75 MHz).  - 194 -  Figure 3.5. 1H NMR spectrum of 173 in d6-DMSO at 25 oC (300 MHz).   Figure 3.6. 13C APT NMR spectrum of 173 in d6-DMSO at 25 oC (75 MHz).  - 195 -  Figure 3.7. 1H NMR spectrum of 175-H2·2HBr in CDCl3/CD3OD at 25 oC (300 MHz).   Figure 3.8. 13C APT NMR spectrum of 175-H2·2HBr in CDCl3/CD3OD at 25 oC (75 MHz).  - 196 -  Figure 3.9. 1H NMR spectrum of 181-H2·2HBr in CDCl3/CD3OD at 25 oC (300 MHz).    Figure 3.10. 13C APT NMR spectrum of 181-H2·2HBr in CDCl3/CD3OD at 25 oC (75 MHz).  - 197 -  Figure 3.11. 1H NMR spectrum of 193 in d6-DMSO at 25 oC (300 MHz).    Figure 3.12. 13C APT NMR spectrum of 193 in d6-DMSO at 25 oC (75 MHz).  - 198 -  Figure 3.13. 1H NMR spectrum of 201 in d6-DMSO at 25 oC (300 MHz).    Figure 3.14. 13C APT NMR spectrum of 201 in d6-DMSO at 25 oC (75 MHz).  - 199 -  Figure 3.15. 1H NMR spectrum of 202 in d6-DMSO at 25 oC (300 MHz).    Figure 3.16. 13C APT NMR spectrum of 202 in d6-DMSO at 25 oC (75 MHz).  - 200 -  Figure 3.17. 1H NMR spectrum of 203 in d6-DMSO at 25 oC (300 MHz).    Figure 3.18. 13C APT NMR spectrum of 203 in d6-DMSO at 25 oC (75 MHz).  - 201 -  Figure 3.19. 1H1H COSY spectrum of 203 in d6-DMSO at 25 oC (400 MHz).  - 202 -  Figure 3.20. 1H NMR spectrum of 220-H2·2HBr in CD3OD at 25 oC (300 MHz).     - 203 -  Figure 3.21. 13C APT NMR spectrum of 221 in CD2Cl2 at 25 oC (75 MHz).   Figure 3.22. 13C APT NMR spectrum of 222 in CD2Cl2 at 25 oC (75 MHz).  - 204 -  Figure 3.23. 1H NMR spectrum of 223 in CD2Cl2 at 25 oC (300 MHz).   Figure 3.24. 1H NMR spectrum of 224 in CD2Cl2 at 25 oC (300 MHz).  - 205 -  Figure 3.25. 1H NMR spectrum of 226 in CD2Cl2 at 25 oC (300 MHz).   Figure 3.26. 1H NMR spectrum of 227 in CD2Cl2 at 25 oC (300 MHz).  - 206 -  Figure 3.27. 1H NMR spectrum of 236 in d6-acetone at 25 oC (300 MHz).   Figure 3.28. 13C APT NMR spectrum of 236 in d6-acetone at 25 oC (75 MHz).  - 207 -  Figure 3.29. 1H NMR spectrum of 237 in d6-acetone at 25 oC (300 MHz).    Figure 3.30. 13C APT NMR spectrum of 237 in d6-acetone at 25 oC (75 MHz).  - 208 -  Figure 3.31. 1H NMR spectrum of 238 in d6-acetone at 25 oC (300 MHz).    Figure 3.32. 13C APT NMR spectrum of 238 in d6-acetone at 25 oC (75 MHz).  - 209 -  Figure 3.33. 1H NMR spectrum of 248 in d6-acetone at 25 oC (300 MHz).    Figure 3.34. 13C APT NMR spectrum of 248 in CD2Cl2 at 25 oC (75 MHz).  - 210 -  Figure 3.35. 1H NMR spectrum of 250-H2 in CD2Cl2 at 25 oC (300 MHz).    Figure 3.36. 13C APT NMR spectrum of 250-H2 in CD2Cl2 at 25 oC (75 MHz).  - 211 -  Figure 3.37. 1H NMR spectrum of 252 in CD2Cl2 at 25 oC (300 MHz).    Figure 3.38. 1H NMR spectrum of 255 in CD2Cl2 at 25 oC (300 MHz).  - 212 -  Figure 3.39. 1H NMR spectrum of 257 in CDCl3 at 25 oC (300 MHz).    Figure 3.40. 13C APT NMR spectrum of 257 in CDCl3 at 25 oC (75 MHz).  - 213 -  Figure 3.41. 1H NMR spectrum of 259 in CD3CN at 25 oC (300 MHz).   Figure 3.42. 13C APT NMR spectrum of 259 in CDCl3 at 25 oC (75 MHz).  - 214 -  Figure 3.43. 1H NMR spectrum of 260-H2 in CD2Cl2 at 25 oC (300 MHz).    Figure 3.44. 13C APT NMR spectrum of 260-H2 in CD2Cl2 at 25 oC (75 MHz).  - 215 -  Figure 3.45. 1H NMR spectrum of 262 in CD2Cl2 at 25 oC (300 MHz).    Figure 3.46. 13C APT NMR spectrum of 262 in CD2Cl2 at 25 oC (75 MHz).  - 216 -  Figure 3.47. 1H NMR spectrum of 264 in CD2Cl2 at 25 oC (300 MHz).    Figure 3.48. 13C APT NMR spectrum of 264 in CD2Cl2 at 25 oC (75 MHz).  - 217 -  Figure 3.49. 1H NMR spectrum of 265 in CD2Cl2 at 25 oC (300 MHz).  Figure 3.50. 13C APT NMR spectrum of 265 in CD2Cl2 at 25 oC (75 MHz).  * The peaks belong to the mesocate In22603.  - 218 - REFERENCES  (1) von Zelewsky, A. Stereochemistry of Coordination Compounds; John Wiley & Sons: New York, 1996.  (2) Piguet, C.; Bernardinelli, G.; Hopfgartner, G. Chem. Rev. 1997, 97, 2005-2062.  (3) Albrecht, M. Chem. Rev. 2001, 101, 3457-3497.  (4) Pascu, G. I.; Hotze, A. C. G.; Sanchez-Cano, C.; Kariuki, B. M.; Hannon, M. J. Angew. Chem., Int. Ed. 2007, 46, 4374-4378.  (5) Vandevyver, C. D. B.; Chauvin, A. S.; Comby, S.; Bunzli, J. C. G. Chem. Commun 2007, 1716-1718.  (6) Albrecht, M.; Kotila, S. Angew. Chem., Int. Ed. Engl. 1995, 34, 2134-2137.  (7) Piguet, C.; Hopfgartner, G.; Bocquet, B.; Schaad, O.; Williams, A. F. J. Am. Chem. Soc. 1994, 116, 9092-9102.  (8) Stratton, W. J.; Busch, D. H. J. Am. Chem. Soc. 1958, 80, 1286-1289.  (9) Stratton, W. J.; Busch, D. H. J. Am. Chem. Soc. 1858, 80, 3191-3195.  (10) Stratton, W. J.; Busch, D. H. J. Am. Chem. Soc. 1960, 82, 4834-4839.  (11) Harris, C. M.; McKenzie, E. D. J. Chem. Soc. (A) 1969, 746-753.  (12) Carrano, C. J.; Raymond, K. N. J. Am. Chem. Soc. 1978, 100, 5371-5374.  (13) Scarrow, R. C.; White, D. L.; Raymond, K. N. J. Am. Chem. Soc. 1985, 107, 6540-6546.  (14) Albrecht, M. Tetrahedron 1996, 52, 2385-2394.  (15) Albrecht, M.; Kotila, S. Chem. Commun 1996, 2309-2310.  - 219 -  (16) Albrecht, M.; Kotila, S. Angew. Chem., Int. Ed. Engl. 1996, 35, 1208-1210.  (17) Albrecht, M. Synthesis 1996, 230-237.  (18) Albrecht, M.; Schneider, M. Synthesis 2000, 1557-1560.  (19) Albrecht, M. Chem. Eur. J. 2000, 6, 3485-3489.  (20) Albrecht, M.; Rottele, H.; Burger, P. Chem. Eur. J. 1996, 2, 1264-1268.  (21) Albrecht, M.; Riether, C. Chem. Ber. 1996, 129, 829-832.  (22) Kersting, B.; Meyer, M.; Powers, R. E.; Raymond, K. N. J. Am. Chem. Soc. 1996, 118, 7221-7222.  (23) Xu, J. D.; Parac, T. N.; Raymond, K. N. Angew. Chem., Int. Ed. 1999, 38, 2878-2882.  (24) Goetz, S.; Kruger, P. E. Dalton Trans. 2006, 1277-1284.  (25) Kramer, R.; Lehn, J. M.; Decian, A.; Fischer, J. Angew. Chem., Int. Ed. Engl. 1993, 32, 703-706.  (26) Ferrere, S.; Elliott, C. M. Inorg. Chem. 1995, 34, 5818-5824.  (27) Larson, S. L.; Hendrickson, S. M.; Ferrere, S.; Derr, D. L.; Elliott, C. M. J. Am. Chem. Soc. 1995, 117, 5881-5882.  (28) Elliott, C. M.; Derr, D. L.; Ferrere, S.; Newton, M. D.; Liu, Y. P. J. Am. Chem. Soc. 1996, 118, 5221-5228.  (29) Jodry, J. J.; Lacour, J. Chem. Eur. J. 2000, 6, 4297-4304.  (30) Lacour, J.; Jodry, J. J.; Monchaud, D. Chem. Commun 2001, 2302-2303.  (31) Zurita, D.; Baret, P.; Pierre, J. L. New J. Chem. 1994, 18, 1143-1146.  (32) Murner, H.; von Zelewsky, A.; Hopfgartner, G. Inorg. Chim. Acta 1998, 271, 36-39.  - 220 -  (33) Baret, P.; Gaude, D.; Gellon, G.; Pierre, J. L. New J. Chem. 1997, 21, 1255-1257.  (34)Prabaharan, R.; Fletcher, N. C.; Nieuwenhuyzen, M. J. Chem. Soc., Dalton Trans. 2002, 602-608.  (35) Prabaharan, R.; Fletcher, N. C. Inorg. Chim. Acta 2003, 355, 449-453.  (36) Lutzen, A.; Hapke, M.; Griep-Raming, J.; Haase, D.; Saak, W. Angew. Chem., Int. Ed. 2002, 41, 2086-2089.  (37) Kiehne, U.; Lutzen, A. Org. Lett. 2007, 9, 5333-5336.  (38) Kiehne, U.; Weilandt, T.; Lutzen, A. Eur. J. Org. Chem. 2008, 2056-2064.  (39) Williams, A. F.; Piguet, C.; Bernardinelli, G. Angew. Chem., Int. Ed. Engl. 1991, 30, 1490-1492.  (40) Charbonniere, L. J.; Bernardinelli, G.; Piguet, C.; Sargeson, A. M.; Williams, A. F. J. Chem. Soc., Chem. Commun. 1994, 1419-1420.  (41) Charbonniere, L. J.; Gilet, M. F.; Bernauer, K.; Williams, A. F. Chem. Commun 1996, 39-40.  (42)Charbonniere, L. J.; Williams, A. F.; Frey, U.; Merbach, A. E.; Kamalaprija, P.; Schaad, O. J. Am. Chem. Soc. 1997, 119, 2488-2496.  (43) Charbonniere, L. J.; Williams, A. F.; Piguet, C.; Bernardinelli, G.; Rivara-Minten, E. Chem. Eur. J. 1998, 4, 485-493.  (44) Bernardinelli, G.; Piguet, C.; Williams, A. F. Angew. Chem., Int. Ed. Engl. 1992, 31, 1622-1624.  - 221 -  (45) Piguet, C.; Bunzli, J. C. G.; Bernardinelli, G.; Hopfgartner, G.; Williams, A. F. J. Am. Chem. Soc. 1993, 115, 8197-8206.  (46) Hamacek, J.; Blanc, S.; Elhabiri, M.; Leize, E.; Van Dorsselaer, A.; Piguet, C.; Albrecht-Gary, A. M. J. Am. Chem. Soc. 2003, 125, 1541-1550.  (47) Elhabiri, M.; Hamacek, J.; Bunzli, J. C. G.; Albrecht-Gary, A. M. Eur. J. Inorg. Chem. 2004, 51-62.  (48)Martin, N.; Bunzli, J. C. G.; McKee, V.; Piguet, C.; Hopfgartner, G. Inorg. Chem. 1998, 37, 577-589.  (49) Elhabiri, M.; Scopelliti, R.; Bunzli, J. C. G.; Piguet, C. Chem. Commun 1998, 2347-2348.  (50) Elhabiri, M.; Scopelliti, R.; Bunzli, J. C. G.; Piguet, C. J. Am. Chem. Soc. 1999, 121, 10747-10762.  (51) Iglesias, C. P.; Elhabiri, M.; Hollenstein, M.; Bunzli, J. C. G.; Piguet, C. J. Chem. Soc., Dalton Trans. 2000, 2031-2043.  (52) Chauvin, A. S.; Comby, S.; Song, B.; Vandevyver, C. D. B.; Thomas, F.; Bunzli, J. C. G. Chem. Eur. J. 2007, 13, 9515-9526.  (53) Andre, N.; Scopelliti, R.; Hopfgartner, G.; Piguet, C.; Bunzli, J. C. G. Chem. Commun 2002, 214-215.  (54) Andre, N.; Jensen, T. B.; Scopelliti, R.; Imbert, D.; Elhabiri, M.; Hopfgartner, G.; Piguet, C.; Bunzli, J. C. G. Inorg. Chem. 2004, 43, 515-529.  (55) Jensen, T. B.; Scopelliti, R.; Bunzli, J. C. G. Chem. Eur. J. 2007, 13, 8404-8410.  - 222 -  (56) Jensen, T. B.; Scopelliti, R.; Bunzli, J. C. G. Inorg. Chem. 2006, 45, 7806-7814.  (57) Jensen, T. B.; Scopelliti, R.; Bunzli, J. C. G. Dalton Trans. 2008, 1027-1036.  (58) Bocquet, B.; Bernardinelli, G.; Ouali, N.; Floquet, S.; Renaud, F.; Hopfgartner, G.; Piguet, C. Chem. Commun 2002, 930-931.  (59) Floquet, S.; Ouali, N.; Bocquet, B.; Bernardinelli, G.; Imbert, D.; Bunzli, J. C. G.; Hopfgartner, G.; Piguet, C. Chem. Eur. J. 2003, 9, 1860-1875.  (60) Floquet, S.; Borkovec, M.; Bernardinelli, G.; Pinto, A.; Leuthold, L. A.; Hopfgartner, G.; Imbert, D.; Bunzli, J. C. G.; Piguet, C. Chem. Eur. J. 2004, 10, 1091-1105.  (61) Zeckert, K.; Hamacek, J.; Senegas, J. M.; Dalla-Favera, N.; Floquet, S.; Bernardinelli, G.; Piguet, C. Angew. Chem., Int. Ed. 2005, 44, 7954-7958.  (62) Dalla-Favera, N.; Hamacek, J.; Borkovec, M.; Jeannerat, D.; Ercolani, G.; Piguet, C. Inorg. Chem. 2007, 46, 9312-9322.  (63)Dalla-Favera, N.; Hamacek, J.; Borkovec, M.; Jeannerat, D.; Gumy, F.; Bunzli, J. C. G.; Ercolani, G.; Piguet, C. Chem. Eur. J. 2008, 14, 2994-3005.  (64)Piguet, C.; Bunzli, J. C. G.; Bernardinelli, G.; Hopfgartner, G.; Petoud, S.; Schaad, O. J. Am. Chem. Soc. 1996, 118, 6681-6697.  (65) Cantuel, M.; Bernardinelli, G.; Muller, G.; Riehl, J. P.; Piguet, C. Inorg. Chem. 2004, 43, 1840-1849.  (66) Cantuel, M.; Gumy, F.; Bunzli, J. C. G.; Piguet, C. Dalton Trans. 2006, 2647-2660.  (67) Riis-Johannessen, T.; Dupont, N.; Canard, G.; Bernardinelli, G.; Hauser, A.; Piguet, C. Dalton Trans. 2008, 3661-3677.  - 223 -  (68) Hannon, M. J.; Painting, C. L.; Jackson, A.; Hamblin, J.; Errington, W. Chem. Commun 1997, 1807-1808.  (69) He, C.; Duan, C. Y.; Fang, C. J.; Meng, Q. J. J. Chem. Soc., Dalton Trans. 2000, 2419-2424.  (70) Muller, J.; Lippert, B. Angew. Chem., Int. Ed. 2006, 45, 2503-2505.  (71) Tuna, F.; Lees, M. R.; Clarkson, G. J.; Hannon, M. J. Chem. Eur. J. 2004, 10, 5737-5750.  (72) Pelleteret, D.; Clerac, R.; Mathoniere, C.; Harte, E.; Schmitt, W.; Kruger, P. E. Chem. Commun 2009, 221-223.  (73) Hamblin, J.; Jackson, A.; Alcock, N. W.; Hannon, M. J. J. Chem. Soc., Dalton Trans. 2002, 1635-1641.  (74) Matthews, C. J.; Onions, S. T.; Morata, G.; Davis, L. J.; Heath, S. L.; Price, D. J. Angew. Chem., Int. Ed. 2003, 42, 3166-3169.  (75) Albrecht, M. Chem. Eur. J. 1997, 3, 1466-1471.  (76) Albrecht, M. Synlett 1996, 565-567.  (77) Albrecht, M.; Janser, I.; Frohlich, R. Chem. Commun 2005, 157-165.  (78) Janser, I.; Albrecht, M.; Hunger, K.; Burk, S.; Rissanen, K. Eur. J. Inorg. Chem. 2006, 244-251.  (79) Enemark, E. J.; Stack, T. D. P. Angew. Chem., Int. Ed. Engl. 1995, 34, 996-998.  (80) Scherer, M.; Caulder, D. L.; Johnson, D. W.; Raymond, K. N. Angew. Chem., Int. Ed. 1999, 38, 1588-1592.  - 224 -  (81) Albrecht, M.; Schneider, M.; Frohlich, R. New J. Chem. 1998, 22, 753-754.  (82) Kiehne, U.; Lutzen, A. Eur. J. Org. Chem. 2007, 5703-5711.  (83) Kreickmann, T.; Diedrich, C.; Pape, T.; Huynh, H. V.; Grimme, S.; Hahn, F. E. J. Am. Chem. Soc. 2006, 128, 11808-11819.  (84) Hahn, F. E.; Kreickmann, T.; Pape, T. Dalton Trans. 2006, 769-771.  (85) Isfort, C. S.; Kreickmann, T.; Pape, T.; Frohlich, R.; Hahn, F. E. Chem. Eur. J. 2007, 13, 2344-2357.  (86) Hahn, F. E.; Offermann, M.; Isfort, C. S.; Pape, T.; Frohlich, R. Angew. Chem., Int. Ed. 2008, 47, 6794-6797.  (87) Falk, H. The Chemistry of Linear Oligopyrroles and Bile Pigments; Springer-Verlag: New York, 1989.  (88) Van koeveringe, J. A.; Lugtenburg, J. Recl. Trav. Chim. Pays-Bas 1977, 96, 55-58.  (89) Paine, J. B. In The Porphyrins; Dolphin, D., Ed.; Academic Press: New York, 1978; Vol. 1.  (90)Fischer, H.; Orth, H. Die Chemie des Pyrrols; kademische Verlagsgesellschaft: Leipzig, 1940.  (91) Nagarkat, J. P.; Ashley, K. R. Synthesis 1974, 186-187.  (92) Casiraghi, G.; Cornia, M.; Rassu, G.; Delsante, C.; Spanu, P. Tetrahedron 1992, 48, 5619-5628.  (93) Lee, C. H.; Lindsey, J. S. Tetrahedron 1994, 50, 11427-11440.  - 225 -  (94) Littler, B. J.; Miller, M. A.; Hung, C. H.; Wagner, R. W.; O'Shea, D. F.; Boyle, P. D.; Lindsey, J. S. J. Org. Chem. 1999, 64, 1391-1396.  (95) Laha, J. K.; Dhanalekshmi, S.; Taniguchi, M.; Ambroise, A.; Lindsey, J. S. Org. Process Res. Dev. 2003, 7, 799-812.  (96) Dolensky, B.; Kroulik, J.; Kral, V.; Sessler, J. L.; Dvorakova, H.; Bour, P.; Bernatkova, M.; Bucher, C.; Lynch, V. J. Am. Chem. Soc. 2004, 126, 13714-13722.  (97) Hungerford, N. L.; Armitt, D. J.; Banwell, M. G. Synthesis 2003, 1837-1843.  (98) Tsuchimoto, T.; Hatanaka, K.; Shirakawa, E.; Kawakami, Y. Chem. Commun 2003, 2454-2455.  (99) Padmavathi, V.; Reddy, B. J. M.; Subbaiah, D. New J. Chem. 2004, 28, 1479-1483.  (100) Murakami, Y.; Matsuda, Y.; Sakata, K.; Harada, K. Bull. Chem. Soc. Jpn. 1974, 47, 458-462.  (101) Wagner, R. W.; Lindsey, J. S. J. Am. Chem. Soc. 1994, 116, 9759-9760.  (102) Bruckner, C.; Karunaratne, V.; Rettig, S. J.; Dolphin, D. Can. J. Chem. 1996, 74, 2182-2193.  (103) Wood, T. E.; Thompson, A. Chem. Rev. 2007, 107, 1831-1861.  (104) Murakami, Y.; Sakata, K. Bull. Chem. Soc. Jpn. 1974, 47, 3025-3028.  (105) March, F. C.; Couch, D. A.; Emerson, K.; Fergusso.Je; Robinson, W. T. J. Chem. Soc. (A) 1971, 440-448.  (106) Murakami, Y.; Matsuda, Y.; Iiyama, K. Chem. Lett. 1972, 1069-1072.  - 226 -  - 227 -  (107) Murakami, Y.; Sakata, K.; Harada, K.; Matsuda, Y. Bull. Chem. Soc. Jpn. 1974, 47, 3021-3024.  (108) Bruckner, C.; Zhang, Y. J.; Rettig, S. J.; Dolphin, D. Inorg. Chim. Acta 1997, 263, 279-286.  (109) Thoi, V. S.; Stork, J. R.; Magde, D.; Cohen, S. M. Inorg. Chem. 2006, 45, 10688-10697.  (110) Halper, S. R.; Stork, J. R.; Cohen, S. M. Dalton Trans. 2007, 1067-1074.  (111) Grigg, R.; Johnson, A. W.; Kenyon, R.; Math, V. B.; Richards.K J. Chem. Soc. (C) 1969, 176-182.  (112) Grigg, R.; Johnson, A. W. J. Chem. Soc. 1964, 3315-3322.  (113) Nonell, S.; Bou, N.; Borrell, J. I.; Teixido, J.; Villanueva, A.; Juarranz, A.; Canete, M. Tetrahedron Lett. 1995, 36, 3405-3408.  (114) Paine, J. B.; Dolphin, D. Can. J. Chem. 1978, 56, 1710-1712.  (115) Cheng, J. M.; Gano, J. E.; Morgan, A. R. Tetrahedron Lett. 1996, 37, 2721-2724.  (116) Zhang, Y. J.; Thompson, A.; Rettig, S. J.; Dolphin, D. J. Am. Chem. Soc. 1998, 120, 13537-13538.  (117) Thompson, A.; Dolphin, D. J. Org. Chem. 2000, 65, 7870-7877.  (118) Dolphin, D.; Harris, R. L. N.; Huppatz, J. L.; Johnson, A. W.; Kay, I. T. J. Chem. Soc. (C) 1966, 30-40.  (119) Dolphin, D.; Harris, R. L. N.; Huppatz, J. L.; Johnson, A. W.; Kay, I. T.; Leng, J. J. Chem. Soc. (C) 1966, 98-101.  - 228 -  (120) Chen, Q. Q.; Zhang, Y. J.; Dolphin, D. Tetrahedron Lett. 2002, 43, 8413-8416.  (121) Wood, T. E.; Ross, A. C.; Dalgleish, N. D.; Power, E. D.; Thompson, A.; Chen, X. M.; Okamoto, Y. J. Org. Chem. 2005, 70, 9967-9974.  (122) Wood, T. E.; Dalgleish, N. D.; Power, E. D.; Thompson, A.; Chen, X. M.; Okamoto, Y. J. Am. Chem. Soc. 2005, 127, 5740-5741.  (123) Thompson, A.; Rettig, S. J.; Dolphin, D. Chem. Commun 1999, 631-632.  (124) Ma, L.; Shin, J. Y.; Patrick, B. O.; Dolphin, D. CrystEngComm 2008, 10, 1539-1541.  (125) Cohen, S. M.; Halper, S. R. Inorg. Chim. Acta 2002, 341, 12-16.  (126) Yu, L. H.; Muthukumaran, K.; Sazanovich, I. V.; Kirmaier, C.; Hindin, E.; Diers, J. R.; Boyle, P. D.; Bocian, D. F.; Holten, D.; Lindsey, J. S. Inorg. Chem. 2003, 42, 6629-6647.  (127) Ulrich, G.; Ziessel, R.; Harriman, A. Angew. Chem., Int. Ed. 2008, 47, 1184-1201.  (128) Loudet, A.; Burgess, K. Chem. Rev. 2007, 107, 4891-4932.  (129) Sazanovich, I. V.; Kirmaier, C.; Hindin, E.; Yu, L. H.; Bocian, D. F.; Lindsey, J. S.; Holten, D. J. Am. Chem. Soc. 2004, 126, 2664-2665.  (130) Smalley, S. J.; Waterland, M. R.; Telfer, S. G. Inorg. Chem. 2009, 48, 13-15.  (131) Paine, J. B.; Dolphin, D. J. Org. Chem. 1985, 50, 5598-5604.  (132) Wijesekera, T. P.; Paine, J. B.; Dolphin, D. J. Org. Chem. 1988, 53, 1345-1352.  (133) Jones, R. A. Pyrroles; Wiley: New York, 1990.  (134) Taniguchi, M.; Balakumar, A.; Fan, D. Z.; McDowell, B. E.; Lindsey, J. S. J. Porphyrins Phthalocyanines 2005, 9, 554-574.  - 229 -  (135) Robinsohn, A. E.; Buldain, G. Y. J. Heterocycl. Chem. 1995, 32, 1567-1572.  (136) Alhazimi, H. M. G.; Jackson, A. H.; Knight, D. W.; Lash, T. D. J. Chem. Soc., Perkin Trans. 1 1987, 265-276.  (137) Setsune, J.; Hashimoto, M. J. Chem. Soc., Chem. Commun. 1994, 657-658.  (138) Paine, J. B.; Woodward, R. B.; Dolphin, D. J. Org. Chem. 1976, 41, 2826-2835.  (139) Sonnet, P. E. J. Org. Chem. 1971, 36, 1005-1007.  (140) Mitsui, T.; Kimoto, M.; Sato, A.; Yokoyama, S.; Hirao, I. Bioorg. Med. Chem. Lett. 2003, 13, 4515-4518.  (141) Bamfield, P.; Johnson, A. W.; Leng, J. J. Chem. Soc. 1965, 7001-7005.  (142) Kumar, R.; Kumar, D.; Chakraborti, A. K. Synthesis 2007, 299-303.  (143) Denmark, S. E.; Willson, T. M. In Selectivities in Lewis Acid Promoted Reactions; Schinzer, D., Ed.; Kluwer Academic Publishers: Dordrecht, 1989.  (144) Santelli, M.; Pons, J.-M. Lewis Acids and Selectivity in Organic Synthesis; CRC Press: Boca Raton, 1996.  (145) Mayr, H.; Gorath, G. J. Am. Chem. Soc. 1995, 117, 7862-7868.  (146) Chmielewski, P. J.; Latosgrazynski, L.; Rachlewicz, K.; Glowiak, T. Angew. Chem., Int. Ed. Engl. 1994, 33, 779-781.  (147) Furuta, H.; Asano, T.; Ogawa, T. J. Am. Chem. Soc. 1994, 116, 767-768.  (148) Furuta, H.; Maeda, H.; Osuka, A. J. Org. Chem. 2001, 66, 8563-8572.  (149) Milgram, B. C.; Eskildsen, K.; Richter, S. M.; Scheidt, W. R.; Scheidt, K. A. J. Org. Chem. 2007, 72, 3941-3944.  - 230 -  (150) Jeon, K. O.; Jun, J. H.; Yu, J. S.; Lee, C. K. J. Heterocycl. Chem. 2003, 40, 763-771.  (151) Decreau, R. A.; Collman, J. P. Tetrahedron Lett. 2003, 44, 3323-3327.  (152) Landrum, J. T.; Hatano, K.; Scheidt, W. R.; Reed, C. A. J. Am. Chem. Soc. 1980, 102, 6729-6735.  (153) Daugherty, P. A.; Glerup, J.; Goodson, P. A.; Hodgson, D. J.; Michelsen, K. Acta Chem. Scand. 1991, 45, 244-253.  (154) Hazra, S.; Naskar, S.; Mishra, D.; Gorelsky, S. I.; Figgie, H. M.; Sheldrick, W. S.; Chattopadhyay, S. K. Dalton Trans. 2007, 4143-4148.  (155) Kersting, B.; Telford, J. R.; Meyer, M.; Raymond, K. N. J. Am. Chem. Soc. 1996, 118, 5712-5721.  (156) Wood, T. E.; Ross, A. C.; Dalgleish, N. D.; Power, E. D.; Thompson, A.; Chen, X.; Okamoto, Y. J. Org. Chem. 2005, 70, 9967-9974.  (157) Albrecht, M.; Janser, I.; Houjou, H.; Frohlich, R. Chem. Eur. J. 2004, 10, 2839-2850.  (158) Mal, P.; Schultz, D.; Beyeh, K.; Rissanen, K.; Nitschke, J. R. Angew. Chem., Int. Ed. 2008, 47, 8297-8301.  (159) Mal, P.; Breiner, B.; Rissanen, K.; Nitschke, J. R. Science 2009, 324, 1697-1699.  (160) Harvey, J. D.; Ziegler, C. J. Coord. Chem. Rev. 2003, 247, 1-19.  (161) Ghosh, A. Angew. Chem., Int. Ed. 2004, 43, 1918-1931.  (162) Maeda, H.; Furuta, H. Pure Appl. Chem. 2006, 78, 29-44.  - 231 -  (163) Altomare, A.; Burla, M. C.; Camalli, M.; Cascarano, G. L.; Giacovazzo, C.; Guagliardi, A.; Moliterni, A. G. G.; Polidori, G.; Spagna, R. J. Appl. Crystallogr. 1999, 32, 115-119. 

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