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Excited-state intramolecular proton-transfer reaction demonstrating anti-Kasha behavior.

ABSTRACT: We report unusual photophysical properties observed on two newly designed 3-hydroxychromone derivatives exhibiting the excited-state intramolecular proton transfer (ESIPT) reaction. The efficiency of ESIPT reaction is greatly enhanced upon excitation with high energy quanta to S n (n > 1) levels in low-polarity solvents. Based on detailed analyses of excitation and emission spectra as well as time-resolved emission kinetics we derive that conditions, in which this phenomenon contradicting Kasha's rule is observed, are quite different from that for observation of anti-Kasha emission.

SUBMITTER: Tseng HW

PROVIDER: S-EPMC5952995 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Excited-state intramolecular proton-transfer reaction demonstrating anti-Kasha behavior.

Tseng Huan-Wei HW Shen Jiun-Yi JY Kuo Ting-Yi TY Tu Ting-Syun TS Chen Yi-An YA Demchenko Alexander P AP Chou Pi-Tai PT

Chemical science 20151012 1

We report unusual photophysical properties observed on two newly designed 3-hydroxychromone derivatives exhibiting the excited-state intramolecular proton transfer (ESIPT) reaction. The efficiency of ESIPT reaction is greatly enhanced upon excitation with high energy quanta to S n (n > 1) levels in low-polarity solvents. Based on detailed analyses of excitation and emission spectra as well as time-resolved emission kinetics we derive that conditions, in which this phenom ...[more]

PMID: 29896352

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