Photo‐/Electrochemical Site‐Selective Radical α‐C(sp ³ )–H Functionalization of Amines: Four Green Strategies for Applications, Challenges, and Opportunities

The activation of N‐C(sp 3 )H bonds is essential in various fields, such as bioactive compounds, natural products, pharmaceuticals, and materials science, yet traditional protocols for the radical α‐C(sp 3 )–H functionalization of amines require harsh conditions, suffer from low atom economy, and rely on stoichiometric hazardous oxidants such as peroxides. Hence, the direct activation of the N‐C(sp 3 )H bond under mild or transition‐metal‐free conditions remains a significant challenge. Recently, emerging strategies such as photo‐ or electroinduced single‐electron oxidation (SEO), hydrogen atom transfer (HAT), electron donor–acceptor (EDA) complex formation, and ligand‐to‐metal charge transfer (LMCT) have enabled transformations under mild conditions. Despite substantial progress and growing interest in this area, reviews on photo‐/electrochemical C(sp 3 )–H bond activation and functionalization remain scarce. This article summarizes recent advances (2016–2025) in this rapidly expanding research area, aiming to provide guidance for the sustainable application of photo‐/electrochemical radical α‐C(sp 3 )–H functionalization reactions and to stimulate further progress in this field.