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Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
Photoswitchable Keto-Enol Tautomerism Driven by Light-Induced Change in Antiaromaticity
Hanwei Lu1,2, Hebo Ye1, Meilan Zhang1,3
1State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China.
Abstract:
The bidirectional interconversion between ketone and enol structures of 4-cyclopentene-1,3-dione derivatives was realized by photoswitching of fused dithienylethene using UV and visible light. A loss of antiaromaticity offered the driving force for light-triggered enolization and was supported by theoretical studies. Solvent and substituent effects provided additional means for regulating photoswitchable keto-enol tautomerism. Moreover, a significant change of acidity was revealed with light-induced keto-to-enol conversion, enabling control over base-catalyzed Michael addition.
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