Dual-mode electrochromism switched by proton transfer: dynamic redox properties of bis(diarylmethylenium)-type dyes.
Upon oxidative dimerization of pale yellow Ar2C=CHPh 1 (Ar = 4-Me2NC6H4), deep blue 1,4-dication 2(2+) was obtained as a stable salt, which was transformed into 1 by reductive C-C bond fission; deprotonation of 2(2+) gave intense yellow diene 3, which was interconvertible with violet dication 4(2+) by two-electron transfer, thus exhibiting two distinct modes of electrochromism before and after proton transfer.
Suzuki
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Division of Chemistry, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan. tak@sci.hokudai.ac.jp
Higuchi
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H
Ohkita
M
M
Tsuji
T
T