Photocatalyzed Cyanodifluoromethylation of Alkenes

Difluoromethylation is a straightforward and widely applied strategy used to incorporate HCF₂ into organic molecules. In contrast, cyanation reagents are typically volatile or highly toxic, or they require harsh reaction conditions. Incorporation of both CN and HCF₂ into organic molecules, such as alkenes, is a worthwhile but challenging task. A method for photocatalyzed cyanodifluoromethylation of alkenes has been developed, which employs a Ph₃ P⁺ CF₂ CO₂ ^- /NaNH₂ (or NH₃ ) reagent system. Ph₃ P⁺ CF₂ CO₂ ^- functions as both the HCF₂ and CN carbon source. A cyanide anion is generated in situ under mild conditions, thereby avoiding the use of toxic cyanation reagents. The photocatalytic method permits cyanodifluoromethylation of a range of alkenes under mild room temperature conditions. The CN group within the products may be further derivatized by standard methods.