Photocatalytic regioselective four-component radical relay carbonylation for α-aminoketones synthesis.

Regioselective transformation is among the long-standing challenges in organic synthesis, particularly involving gas trapping. We present here a novel photocatalytic strategy for the regioselective carbonylation reaction toward α-aminoketones. Experimental studies reveal that protonic acids dissociated from protonated amines facilitate the reactions of low-reactive aldehydes and enhance the electrophilicity of imines, thereby promoting the efficient coupling of less nucleophilic acyl radicals. This approach introduces a reliable framework for controlling regioselectivity in photocatalytic multi-radical-coupled CO trapping reactions, broadens the chemical space of α-aminoketones, and advances carbonylation reactions for sustainable development.