Search the site

The University of Manchester Library

In April 2016 Manchester eScholar was replaced by the University of Manchester’s new Research Information Management System, Pure. In the autumn the University’s research outputs will be available to search and browse via a new Research Portal. Until then the University’s full publication record can be accessed via a temporary portal and the old eScholar content is available to search and browse via this archive.

Directed C-H Borylation for the Synthesis of Fused and Ladder Type Conjugated Oligomers and Polymers

Crossley, Daniel

[Thesis]. Manchester, UK: The University of Manchester; 2016.

Access to files

Abstract

The synthesis, photophysical and electronic properties of a series of novel boron containing fused and ladder type donor−acceptor (D-A) oligomers and polymers are reported. The synthesis was achieved through coordination of the basic functionality of the ubiquitous benzothiadiazole acceptor unit onto a boron Lewis acid followed by an electrophilic aromatic borylation resulting in the formation of fused and ladder type structures (termed borylative fusion). The novel C,N-chelated borane structures disclosed herein are a new member of a large family of tetra-coordinate organoboron compounds that are used for the construction of highly emissive materials. Upon borylation large bathochromic shifts in the absorption and fluorescence spectra were observed, DFT and cyclic voltammetry demonstrate that this is a result of a significant reduction of the LUMO energy levels whist the HOMO energy levels remains relatively unperturbed. These large bathochromic shifts lead to materials that show far red/NIR emission in the solid state with absolute quantum yields of up to 44%. Furthermore, the frontier molecular orbital energy levels of these fused structures can be modulated through judicious selection of the exocyclic boron substituents. These novel borocycles also proved stable to a range of cross-coupling conditions which facilitated further modulation of the frontier molecular orbitals and emissive properties. Borylative fusion was also applicable to D-A conjugated polymers, this represents a facile post-polymerisation functionalisation that is an effective method of modulating the photophysical properties of D-A conjugated polymers. Solution processed OLEDs with far red/NIR electroluminescence (EL) were fabricated from these materials. These devices showed good external quantum efficiency values (EQE) for the far red/NIR region of the electromagnetic spectrum (EQE >0.4 % for maximum EL >700 nm).

Layman's Abstract

This thesis describes the synthesis and photophysical properties of tetra-coordinate C,N-chelated donor-acceptor organoboron compounds.

Bibliographic metadata

Type of resource:
Content type:
Administered thesis
Form of thesis:
Traditional
Type of submission:
Doctoral level ETD - final
Thesis title:
Directed C-H Borylation for the Synthesis of Fused and Ladder Type Conjugated Oligomers and Polymers
Degree type:
Doctor of Philosophy
Degree programme:
PhD Chemistry (42 month)
Publication date:
2016-06-21T11:43:16
Institution:
The University of Manchester
Location:
Manchester, UK
Total pages:
271
Abstract:
The synthesis, photophysical and electronic properties of a series of novel boron containing fused and ladder type donor−acceptor (D-A) oligomers and polymers are reported. The synthesis was achieved through coordination of the basic functionality of the ubiquitous benzothiadiazole acceptor unit onto a boron Lewis acid followed by an electrophilic aromatic borylation resulting in the formation of fused and ladder type structures (termed borylative fusion). The novel C,N-chelated borane structures disclosed herein are a new member of a large family of tetra-coordinate organoboron compounds that are used for the construction of highly emissive materials. Upon borylation large bathochromic shifts in the absorption and fluorescence spectra were observed, DFT and cyclic voltammetry demonstrate that this is a result of a significant reduction of the LUMO energy levels whist the HOMO energy levels remains relatively unperturbed. These large bathochromic shifts lead to materials that show far red/NIR emission in the solid state with absolute quantum yields of up to 44%. Furthermore, the frontier molecular orbital energy levels of these fused structures can be modulated through judicious selection of the exocyclic boron substituents. These novel borocycles also proved stable to a range of cross-coupling conditions which facilitated further modulation of the frontier molecular orbitals and emissive properties. Borylative fusion was also applicable to D-A conjugated polymers, this represents a facile post-polymerisation functionalisation that is an effective method of modulating the photophysical properties of D-A conjugated polymers. Solution processed OLEDs with far red/NIR electroluminescence (EL) were fabricated from these materials. These devices showed good external quantum efficiency values (EQE) for the far red/NIR region of the electromagnetic spectrum (EQE >0.4 % for maximum EL >700 nm).
Layman's abstract:
This thesis describes the synthesis and photophysical properties of tetra-coordinate C,N-chelated donor-acceptor organoboron compounds.
Keyword(s):
Thesis main supervisor(s):
Thesis co-supervisor(s):
Degree grantor:
Language:
en

Institutional metadata

University researcher(s):
Academic department(s):

Record metadata

Manchester eScholar ID:
uk-ac-man-scw:301616
Created by:
Crossley, Daniel
Created:
21st June, 2016, 10:43:16
Last modified by:
Crossley, Daniel
Last modified:
5th July, 2018, 13:32:31

Can we help?

The library chat service will be available from 11am-3pm Monday to Friday (excluding Bank Holidays). You can also email your enquiry to us.