Photoredox‐Catalyzed Synthesis of Homoallylamines from Unactivated Imines and Allyl Bromides

A photoredox-catalyzed umpolung strategy for the synthesis of homoallylamines from unactivated imines and allyl bromides is described. This strategy exploited N,N-diisopropylethylamine (DIPEA) as an auxiliary agent to indirectly realize the cross-coupling of imines and allyl bromides. Various sterically hindered homoallylamines were synthesized by combining photocatalysis with halogen atom transfer (XAT). Notable characteristics of this approach include water-insensitive reaction conditions, high yield (up to 99%), wide substrate scope (suitable for N-aryl/alkyl and C-aryl ketimines and aldimines, 39 examples), and high tolerance of functional groups (such as cyano, ester, amide, and thioamide).