Photoredox-Catalyzed Defluorinative Carboxylation of gem -Difluorostyrenes with Formate Salt.

Herein, we present a transition-metal-free, easy handling protocol for regioselective carboxylation of gem -difluorostyrenes with sodium formate as the C1 source. 30 examples of α-fluoracrylates were obtained in yields of 30 to 80% under these conditions. A defluorinative monofluorovinyl intermediate and consecutive photoinduced electron transfer mechanism were proposed after mechanism investigation.