Transformation of carbonyl compounds into gem-difluoro compounds with dibromodifluoromethane/zinc reagent

Abstract

Reaction of carbonyl compounds with dibromodifluoromethane/zinc gives the gem-difluoro compounds (12 examples). It seems to be that the reaction involves the generation of difluorocarbene by reaction of dibromodifluoromethane with zinc, followed by production of the difluorocarbonyl ylide. Such an ylide then breaks down the corresponding CF₂ moiety.