Palladium-Catalyzed gem -Difluoroallylation Reaction between Aryltributyltin and Bromodifluoromethylated Alkenes.

A robust Stille gem -difluoroallylation of arylstannanes with 3-bromo-3,3-difluoropropenes has been established. The catalyst was found to exert critical effect on the reaction chemoselectivity. By using Pd(OH) 2 /C as the catalyst, a series of 3-(hetero)aryl/vinyl-3,3-difluoropropenes were obtained in high efficiency with α-substitution regioselectivity. The reaction has a broad substrate scope, and various substitution patterns were well tolerated in both substrates. Notably, the reaction can be easily extended to late-stage gem -difluoroallylation of many bioactive molecules with good chemoselectivity.