Title

Discotic liquid crystalline star-shaped hetero heptamers for organic photovoltaic devices.

Date of Award

2004

Degree Type

Thesis

Degree Name

M.Sc.

Department

Chemistry and Biochemistry

First Advisor

Eichhorn, S. H.

Keywords

Chemistry, Analytical.

Rights

CC BY-NC-ND 4.0

Abstract

This thesis describes synthetic approaches to heteroheptamers of discotic liquid crystals, which should be ideal building blocks for organic photovoltaic devices. Hexaazatriphenylene-hexacarboxylic acid [HAT(CO2H) 6] and its derivatives were chosen as n-type semi-conducting central discotic monomer that has six p-type semi-conducting hexaalkoxytriphenylene discogens covalently attached to it. HAT derivatives were successfully synthesized and their conversions with alkyl alcohols and amines to hexaesters and hexa-amides are discussed. A complete conversion of all acid or ester groups with low molecular weight alcohols and amines was not achieved but transesterification of the hexa-methylester with alkyl alcohols catalyzed by titanium (IV) isopropoxide gave 80--90% conversion. Optimization of the reaction conditions should result in a 100% conversion. Monofunctionalized hexaalkoxytriphenylene derivatives were chosen as p-type semi-conducting ligands and several different synthetic pathways towards these triphenylene derivatives are presented. Several approaches based on statistical cyclization to the triphenylene or statistical cleavage of one alkoxy group have been reported in literature. We, however, could not reproduce the reported yields and found the Suzuki cross-coupling pathway to be the most reliable and highest yielding synthetic approach. The preparation of heteroheptamers containing [HAT(CO2H) 6] as central core and hexaalkoxytriphenylene derivatives as ligands should be straightforward based on the synthetic approaches that have been developed in this thesis. (Abstract shortened by UMI.)Dept. of Chemistry and Biochemistry. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2003 .J35. Source: Masters Abstracts International, Volume: 43-01, page: 0211. Adviser: Holger Eichhorn. Thesis (M.Sc.)--University of Windsor (Canada), 2004.