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Published on: February 7, 2022
Stimuli-Controlled Keto-Enol Tautomerism of Extended Unsaturated Carbonyls for Gating Photoswitching of Diarylethenes
Jiafan Xin1,2,3, Mingyu Xie1,2,3, Hanwei Lu2
1College of Chemistry, Fuzhou University, Fuzhou 350108, P. R. China.
Abstract:
Gated photoswitching systems, which enable control over photochromic properties, play an important role in chemistry. Here, we present a novel gated system based on extended unsaturated 1,3-dicarbonyl derivatives of diarylethenes by manipulating keto-enol tautomerism. While the intramolecular charge transfer process blocked the photochromism, the creation of an ester enabled efficient bidirectional photoswitching. The use of acid/base further induced a shift of the keto-enol equilibrium. Finally, switchable multistep gating control of the photochrome was achieved, enhancing the complexity.
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