Recent advances in the transformation of nitriles into diverse N-heterocycles

Abstract

Nitriles, as valuable compounds characterized by carbon–nitrogen triple bonds, represent an important class of synthons in organic synthetic chemistry and materials science. Over the past two decades, the conversion of nitriles to diverse N-heterocycles has attracted significant attention among chemists, owing to its numerous synthetic and economic advantages. Three main types of reactions involving nitriles in N-heterocycle synthesis have been reported, including nucleophilic addition, electrophilic addition and radical addition reactions. In this review, a comprehensive overview of recent progress in nitrile cyclization chemistry is presented. This review is organized and discussed based on the transition metal-catalyzed and metal-free induced N-heterocycle synthesis by C–C, C–N and N–N bond formation reactions using nitriles as nitrogen sources, with an emphasis on the reaction development, mechanisms and subsequent applications of these reactions.