- Library Home /
- Search Collections /
- Open Collections /
- Browse Collections /
- UBC Theses and Dissertations /
- Synthesis and polymerization of spiro-orthoesters catalyzed...
Open Collections
UBC Theses and Dissertations
UBC Theses and Dissertations
Synthesis and polymerization of spiro-orthoesters catalyzed by a cationic indium complex Chang, Chen
Abstract
While numerous neutral indium complexes have been reported to be functional group tolerant Lewis acid catalysts for various transformations, there are only a handful of reported cationic indium complexes; these are mostly inactive in catalytic transformations. Herein, I describe the synthesis and characterization of a rare cationic indium alkyl complex bearing a chiral tridentate ligand, [(NNO)In(CH₂SiMe₃)(THF)][BArF] (30). Complex 30 is active towards reaction of 1,2-epoxy-7-octene and ε-caprolactone to form the corresponding spiro-orthoester (SOE1), where quantitative conversions of both substrates are achieved under 24 hours at 2.5% catalyst loading at 60 ˚C in benzene. Synthesis of spiro-orthoesters bearing various ether rings are also achieved with different lactone substrates. While preliminary polymerization studies of SOE1 by the cationic indium species 30 suggest the poor activity of this system towards polymerization of SOE1 at low temperature, polymerization of SOE1 complex 30 at 110 ˚C resulted in over 90% conversion of the monomer, and the resulting polymer was tentatively assigned as low molecular weight poly(ether ester). This thesis provides another example of the unusual reactivity of cationic indium complexes, where further investigation of various spiro-orthoesters synthesis and polymerization, as well as exploration of other cationic indium complexes, will be continued in the Mehrkhodavandi group.
Item Metadata
Title |
Synthesis and polymerization of spiro-orthoesters catalyzed by a cationic indium complex
|
Creator | |
Publisher |
University of British Columbia
|
Date Issued |
2017
|
Description |
While numerous neutral indium complexes have been reported to be functional group
tolerant Lewis acid catalysts for various transformations, there are only a handful of reported
cationic indium complexes; these are mostly inactive in catalytic transformations. Herein, I
describe the synthesis and characterization of a rare cationic indium alkyl complex bearing a chiral
tridentate ligand, [(NNO)In(CH₂SiMe₃)(THF)][BArF] (30). Complex 30 is active towards reaction
of 1,2-epoxy-7-octene and ε-caprolactone to form the corresponding spiro-orthoester (SOE1),
where quantitative conversions of both substrates are achieved under 24 hours at 2.5% catalyst
loading at 60 ˚C in benzene. Synthesis of spiro-orthoesters bearing various ether rings are also
achieved with different lactone substrates. While preliminary polymerization studies of SOE1 by
the cationic indium species 30 suggest the poor activity of this system towards polymerization of
SOE1 at low temperature, polymerization of SOE1 complex 30 at 110 ˚C resulted in over 90%
conversion of the monomer, and the resulting polymer was tentatively assigned as low molecular
weight poly(ether ester). This thesis provides another example of the unusual reactivity of cationic
indium complexes, where further investigation of various spiro-orthoesters synthesis and
polymerization, as well as exploration of other cationic indium complexes, will be continued in
the Mehrkhodavandi group.
|
Genre | |
Type | |
Language |
eng
|
Date Available |
2017-05-08
|
Provider |
Vancouver : University of British Columbia Library
|
Rights |
Attribution-NonCommercial-NoDerivatives 4.0 International
|
DOI |
10.14288/1.0347347
|
URI | |
Degree | |
Program | |
Affiliation | |
Degree Grantor |
University of British Columbia
|
Graduation Date |
2017-09
|
Campus | |
Scholarly Level |
Graduate
|
Rights URI | |
Aggregated Source Repository |
DSpace
|
Item Media
Item Citations and Data
Rights
Attribution-NonCommercial-NoDerivatives 4.0 International