Dual Photoexcited Palladium and Photoredox-Catalyzed Remote C(sp3)–H Acylation of Hydroxyamides

Herein, we report an unprecedented dual photoexcited palladium and photoredox-catalyzed remote C(sp3)-H acylation of amides free of external acylating reagents through sequential N-O/C-H/C-O bond cleavage and chemoselective C-C bond formation. This dual catalytic system shows high efficiency, good atom economy by deletion of oxygen, and diverse functional group tolerance. Experimental investigation of the reaction mechanism revealed that O-acyl hydroxamides enabled by photoexcited palladium generated the alkyl radicals via a 1,5-HAT process mediated by amidyl radicals and a palladium carboxylate complex, which, undergoing photoredox-catalyzed phosphoranyl radical-mediated C-O bond cleavage, leads to coupling with alkyl radicals to deliver the final products.