NHC/photoredox dual catalysis directs N-methyl radical coupling for decarboxylative synthesis of α-N-aryl amino ketones

Abstract

Herein, a synergistic NHC/photoredox system enables α-N-aryl amino ketone synthesis via stabilized N-methyl radical intermediates, overcoming competitive dimerization. Key innovations include base-mediated N-methyl radical generation and acyl azolium intermediate-guided cross-coupling, steering reactivity away from parasitic pathways. Electron-rich NHCs (e.g., Mes-substituted) accelerate acyl azolium intermediate formation, achieving a broad substrate scope under mild conditions. Mechanistic studies confirm radical intermediates, while derivatization highlights utility in the synthesis of bioactive molecules. This strategy merges atom economy with scalable, step-economy catalysis.