Enantioconvergent Deoxygenative Amination via Xanthate Esters by a Decarboxylative Relay

Abstract

The direct conversion of alcohols to amines through deoxygenative radical pathways can provide a versatile strategy for constructing C(sp3)–N bonds from simple and abundant precursors, yet catalytic enantioconvergent variants remain undeveloped. We report herein a previously unexplored enantioconvergent deoxygenative amination that proceeds by radical activation of alcohol-derived xanthates via a decarboxylative radical relay process. This transformation is enabled by the merger of acridine photocatalysis, which mediates radical generation, and chiral cobalt(salen) catalysis, which mediates asymmetric radical–polar crossover, producing α-chiral benzylic amines under mild conditions. The method provides efficient access to medicinally relevant amine scaffolds with high enantioselectivity. Mechanistic studies revealed a radical gating manifold in which the cobalt catalyst selectively mediates the C–N coupling with the benzylic radical in preference to a competing decarboxylative amination pathway. Computational investigations further elucidated the structural and electronic factors governing xanthate activation, C–O bond homolysis, and the enantioselective radical gating by the cobalt catalyst. Together, these findings establish a mechanistically distinct platform for asymmetric deoxygenative C–N bond formation and highlight the broader potential of cobalt-catalyzed radical gating based on the radical–polar crossover in the development of enantioconvergent radical relay transformations.