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Title: ipso -Arylative polymerization as a route to π-conjugated polymers: synthesis of poly(3-hexylthiophene)
ipso -Arylative cross-coupling with two 3-hexylthiophene derivatives, (5-bromo-4-hexylthiophen-2-yl)diphenylmethanol and 2-(5-bromo-4-hexylthiophen-2-yl)propan-2-ol, has been used to prepare poly(3-hexylhiophene) (P3HT) as a model conjugated polymer. P3HT with number-average molecular weights ranging from 8–20 kg mol −1 ( Đ 1.4–2.2) was prepared from 5-bromo-4-hexylthiophen-2-yl)diphenylmethanol with a Pd(OAc) 2 /PCy 3 /Cs 2 CO 3 catalyst system. Only oligomerization of 2-(5-bromo-4-hexylthiophen-2-yl)propan-2-ol ( M n ≈ 3 kg mol −1 ) was observed under similar conditions. Studies with model compounds suggest that side reactions involving end-group loss limit ultimate molecular weights.  more » « less
Award ID(s):
1506822
PAR ID:
10077519
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Polymer Chemistry
Volume:
9
Issue:
23
ISSN:
1759-9954
Page Range / eLocation ID:
3223 to 3231
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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