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  • Statistical copolymers of thiophene-3-carboxylates and selenophene-3-carboxylates; 77 Se NMR as a tool to examine copolymer sequence in selenophene-based conjugated polymers
Title: Statistical copolymers of thiophene-3-carboxylates and selenophene-3-carboxylates; 77 Se NMR as a tool to examine copolymer sequence in selenophene-based conjugated polymers
Herein, we demonstrate that homopolymerization and statistical copolymerization of 2-ethylhexyl thiophene-3-carboxylate and 2-ethylhexyl selenophene-3-carboxylate monomers is possible via Suzuki–Miyaura cross-coupling. A commercially available palladium catalyst ([1,3-bis(2,6-di-3-pentylphenyl)imidazol-2-ylidene](3-chloropyridyl)dichloropalladium( ii ) or PEPPSI-IPent) was employed to prepare regioregular conjugated polymers with high molecular weights (∼20–30 kg mol −1 ), and relatively narrow molecular weight distributions. The optical bandgap in the copolymer series could be reduced by increasing the concentration of selenophene-3-carboxylate in the material. Configurational triads were observed in the 1 H NMR spectra of the statistical copolymers, which were assigned using a combination of 2D NMR techniques. The use of a 1 H– 77 Se HSQC spectrum to further examine sequence distribution in the statistical copolymers revealed how 77 Se NMR can be used as a tool to examine the microstructure of Se-containing conjugated polymers.  more » « less
Award ID(s):
2109065
PAR ID:
10426044
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Polymer Chemistry
Volume:
13
Issue:
37
ISSN:
1759-9954
Page Range / eLocation ID:
5316 to 5324
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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