NHC catalyzed radical tandem cyclization: an efficient synthesis of α,α-difluoro-γ-lactam derivatives.

Herein, an N-heterocyclic carbene (NHC) catalyzed radical tandem cyclization reaction of N -allylbromodifluoroacetamides and aldehydes has been developed. This method is an efficient protocol for synthesizing α,α-difluoro-γ-lactam derivatives in moderate to good yields (27 examples, up to 88% yield and 10 : 1 dr). This strategy features mild and metal-free conditions, high efficiency, and a broad substrate scope.