Photoredox Catalysis for the Synthesis of N-CF2H Compounds Using 1-((N-(difluoromethyl)-4-methylphenyl)-sulfonamido)pyridin-1-ium Trifluoromethanesulfonate

Abstract

N-(difluoromethyl)amino (−NCF2H) compounds are of great interest given their unique and underexplored physiochemical properties. The lack of structural diversity in NCF2H compounds is likely due in part to the shortage of protocols for efficient installation. Presented herein is a new shelf-stable pyridinium reagent that enables the direct installation of the N-(difluoromethyl)sulfonamide moiety [N(Ts)CF2H)] onto (hetero)arenes and alkenes for the diversification of aryl and alkyl NCF2H compounds. The described protocol utilizes blue light photoredox catalysis and displays broad functional group tolerance with excellent chemoselectivity. Additional transformations and applicability towards a photoredox continuous flow protocol are also demonstrated.