In this work, we have described an efficient protocol for the photoinduced defluorocarboxylation of α-trifluoromethylstyrene using formate as the CO₂ radical anion precursor, which successfully yields a wide variety of gem-difluorovinylacetic acids with excellent functional group tolerance.

Abstract

Herein, we report an efficient protocol in which formate is used as a precursor of the CO₂ radical anion for the photoinduced defluorocarboxylation of α-trifluoromethylstyrene. A wide range of gem-difluorovinylacetic acids bearing a variety of functional groups were successfully obtained in the absence of metal catalysts. The synthetic value of this protocol was highlighted by successful gram-scale synthesis and late-stage modification for complex biologically active molecules. This protocol provides a complementary method that extends the range of currently available methodologies for accessing the structurally versatile gem-difluoroalkenes.