gem-Difluoroalkenylation of aldehydes and ketones with bis(difluoromethyl)triphenylphosphorane under operationally simple conditions

Aldehydes and ketones were converted to gem-difluoroalkenes under straightforward conditions utilizing bis(difluoromethyl)triphenylphosphorane (PPh₃(CF₂H)₂, 1) as the reagent. This approach eliminates the need for pre-formed phosphorus ylides and extra additives. By heating, the reagent directly generates a difluoromethylene ylide intermediate, facilitating the transformation of aldehydes and less hindered ketones into gem-difluoroalkenes with yields ranging from moderate to excellent. The method offers simple reaction conditions, wide substrate compatibility, and promising prospects for scalability.