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Title: Bent naphthodithiophenes: synthesis and characterization of isomeric fluorophores
Thiophene-containing heteroarenes are one of the most well-known classes of π-conjugated building blocks for photoactive molecules. Isomeric naphthodithiophenes (NDTs) are at the forefront of this research area due to their straightforward synthesis and derivatization. Notably, NDT geometries that are bent – such as naphtho[2,1-b:3,4-b']dithiophene (a-NDT) and naphtho[1,2-b:4,3-b']dithiophene (b-NDT) – are seldom employed as photoactive small molecules. This report investigates how remote substituents impact the photophysical properties of isomeric a- and b-NDTs. The orientation of the thiophene units plays a critical role in the emission: in the a(OHex)R2 series conjugation from the end- caps to the NDT core is apparent, while in the b(Oi-Pent)R2 series minimal change is observed unless strong electron acceptors, such as b(Oi-Pent)(PhCF3)2, are employed. This push–pull acceptor–donor– acceptor (A–D–A) fluorophore exhibits positive fluorosolvatochromism that correlates with increasing solvent polarity parameter, ET(30). In total, these results highlight how remote substituents are able to modulate the emission of isomeric bent NDTs.  more » « less
Award ID(s):
2316854
PAR ID:
10549328
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Editor(s):
Bhalla, Vandana
Publisher / Repository:
Royal Society of Chemistry
Date Published:
Journal Name:
RSC Advances
Volume:
14
Issue:
35
ISSN:
2046-2069
Page Range / eLocation ID:
25120 to 25129
Subject(s) / Keyword(s):
Physical organic chemistry, photoactive molecules
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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