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Title: Synthesis and optical properties of a library of multi-colored isomeric aryldibenzopyrylium halochromic cations
This report describes the synthesis of five new colorful 6-aryldibenzo[b,d]pyrylium cation salts, a largely unexplored structural unit. These rare compounds are benzannulated structural derivatives of the well-known flavylium cations found widespread in natural pigments. These new dyes are directly compared to three previously synthesized 6-aryldibenzo[b,d]pyrylium cation salts as well as eight colorful isomeric 9-aryldibenzo[b,e]pyrylium cation, or 9-arylxanthylium, salts. The 9-arylxanthylium unit is commonly found in the biologically important rhodamine and rosamine dyes, yet six of the analogs presented in this study were either previously unreported or not isolated. The visual and spectroscopic properties of all 16 compounds were analyzed as a function of the structural differences between the compounds. All compounds displayed reversible halochromism in organic solution, displaying bright colors under acidic conditions and becoming colorless under basic conditions.  more » « less
Award ID(s):
2018561
PAR ID:
10474816
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Tetrahedron
Volume:
76
Issue:
23
ISSN:
0040-4020
Page Range / eLocation ID:
131222
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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