Electrochemical Difluoromethylarylation of Alkynes

An unprecedented radical difluoromethylarylation reaction of alkynes has been developed by discovering a new difluoromethylation reagent, CF(2)HSO(2)NTHNHBoc. This air-stable and solid reagent can be prepared in one step from commercially available reagents CF2FISO2Cl and NH(2)NHBoc. The CF2H radical, generated through ferrocene-mediated electrochemical oxidation, participates in an unexplored alkyne addition reaction followed by a challenging 7-membered ring-forming homolytic aromatic substitution step to afford fluorinated dibenzazepines.