Photochromic and fluorescence properties of coumarin fulgimides

Authors: KHAMIS NASSOR ALLY, LEYLA ÖZTÜRK, MAHMUT KÖSE

Abstract: Four new fulgimides possessing a fluorescent coumarin unit were synthesized from the corresponding fulgides, and their photochromic as well as fluorescence properties were investigated. The open-ring forms of coumarin fulgimides were found to exhibit fluorescence in the visible region. Upon exposure to UV light, the fulgimides were transformed into the nonfluorescent closed-ring forms, which can be reverted to the initial fluorescent open-ring forms on exposure to visible light. The efficiency of quenching of fluorescence was as high as 95% at the photostationary state of UV irradiation.

Keywords: Photochromism, fulgide, fulgimide, coumarin, fluorescence switch

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