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Updated: Jul 3, 2026

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
Wavelength-dependent reactivity of a quinolinone: toward a photochromic three-state system
Jérôme Berthet1, Jean-Claude Micheau, Vladimir Lokshin
1CNRS UMR 8009, Lille 2 University, NMR and Photochemistry team, F-59006 Lille Cedex, France.
Abstract:
The photochemical reactivity of the quinolinone 3 was investigated using NMR by monitoring its reactions under appropriate irradiation wavelengths. Besides the irreversible formation of degradation products which were structurally identified, the reversible formation of the enol 4 and cyclobutenol 5 was also observed. The enol and cyclobutenol can be switched or reversed back to the quinolinone 3, resulting in a photochromic three-state system in which the relative ratio of the three components largely depends on the irradiation wavelength used.
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