Photoexcited Copper-Catalyzed Enantioselective Allylic C(sp3)–H Acyloxylation of Acyclic Internal Alkenes

Abstract

The functionalization of C–H bonds streamlines the synthesis of complex molecules by eliminating the need for substrate preactivation. Traditionally, the Kharasch–Sosnovsky reaction, which directly oxidizes allylic C–H bonds into allylic esters under copper catalysis, has been hampered by long reaction times, limited substrate scope, and low enantioselectivity with acyclic olefins. Herein, we present a novel, visible light-driven, copper-catalyzed asymmetric Kharasch–Sosnovsky reaction that overcomes these challenges. This method expands the substrate scope to include acyclic internal alkenes and improves reaction conditions using eco-friendly visible light catalysis. It enhances radical reactivity and achieves superior enantioselectivity and regioselectivity in producing allylic C–H acyloxylation products. This breakthrough significantly advances direct C–H functionalization techniques, offering a more efficient and sustainable approach to synthesizing chiral molecules.