Photocatalytic Generation of Aminium Radical Cations for C–N Bond Formation

Aminium radical cations have been extensively studied as electrophilic aminating species that readily participate in C–N bond forming processes with alkenes and arenes. However, their utility in synthesis has been limited, as their generation required unstable, reactive starting materials and harsh reaction conditions. Visible-light photoredox catalysis has emerged as a platform for the mild production of aminium radical cations from either unfunctionalized or N-functionalized amines. This Perspective covers recent synthetic methods that rely on the photocatalytic generation of aminium radical cations for C–N bond formation, specifically in the context of alkene hydroamination, arene C–H bond amination, and the mesolytic bond cleavage of alkoxyamines.