Visible-Light-Induced Hydrodifluoromethylation of Alkenes with a Bromodifluoromethylphosphonium Bromide.

Bromodifluoromethylphosphonium bromide was solely used as the precursor of difluorocarbene. Herein, an unprecedented visible-light-induced hydrodifluoromethylation of alkenes with bromodifluoromethylphosphonium bromide using H2O and THF as hydrogen sources for the synthesis of difluoromethylated alkanes is described. This difluoromethylation is characterized by mild reaction conditions, ready availability of reagents, and excellent functional-group tolerance.