Visible Light Photoredox-Catalyzed Radical Defluorinative Arylation of α-Trifluoromethyl Alkenes with Aryl Chlorides

Photocatalytic defluorinative cross-coupling reactions of α-trifluoromethyl alkenes with diverse radical precursors have emerged as a powerful strategy for the synthesis of gem-difluoroalkenes. However, the radical defluorinative arylation is relatively rare due to the limitation of aryl radical precursors. Aryl chlorides, as ideal candidates, remain a large challenge in this reaction because of the chemical inertness of the C(sp2)–Cl bond and their high negative reduction potential. Herein, we report a radical defluorinative arylation of α-trifluoromethyl alkenes with aryl chlorides as aryl radical precursors through a consecutive photoinduced electron transfer (ConPET) process. This protocol features mild conditions, operational simplicity, wide substrate scope, and functional group tolerance, producing a diverse range of benzylic gem-difluoroalkenes in moderate to good yields. The scale-up reaction and the valuable transformations of products demonstrate the great potential applications of this approach.