Resonance-Enhanced Excited-State Intramolecular Proton Transfer Emission by Base-Mediated Formation of
Théo Andris1, Timothée Stoerkler1, Gilles Ulrich1
1Institut de Chimie et Procédés pour l'Energie, l'Environnement et la Santé (ICPEES), Equipe Chimie Organique pour la Biologie, les Matériaux et l'Optique (COMBO), UMR CNRS 7515, 25 Rue Becquerel, 67087 Strasbourg Cedex 02, France.
None:
This letter describes the synthesis and structural, photophysical, and theoretical properties of novel fluorescent dyes derived from 2-(2'-hydroxyphenyl)benzoxazole, functionalized by tricyanofuran or α-cyano-γ-lactone groups, prone to undergo an excited-state intramolecular proton transfer (ESIPT) process. We serendipitously found that tricyanofuran can induce the formation of the corresponding lactone in basic media, leading to a highly fluorescent derivative, owing to the formation of a merocyanine in the excited state.
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