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Updated: Mar 24, 2026
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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Photocatalytic Difluoromethylation Cyclization and Dioxygen Trapping: Access to gem-Difluoro-Quinolines
Lianglong Sun1, Xinming Xu1, Qilu Li1
1College of Chemistry and Chemical Engineering, Yantai University, Yantai 264005, P. R. China.
Abstract:
Herein, a novel photocatalytic 6-exo-trig difluoromethylation cyclization and subsquent domino O2 trap version is described. This protocol allows efficient access to structurally diverse 4-(hydroxymethyl)-gem-difluoro-quinolines under mild conditions. Broad substrate scope, good functional group compatibility, biologically active molecule modification, scale-up operation, and further derivatization demonstrate the utility of this protocol. A radical cyclization route was proposed based on radical inhibition experiments, deuterium-labeled experiments, visible-light irradiation on-off test, apparent quantum efficiency (AQE) calculation, and Stern-Volmer fluorescence quenching experiments.
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