Photoinduced Copper-Catalyzed Radical Mizoroki–Heck Reaction with Unactivated Alkyl Iodide

Abstract

Herein, we present a method for copper-catalyzed photoinduced radical Mizoroki–Heck (M-H) reactions utilizing unactivated alkyl iodides and styrene. This approach enables the smooth generation of (E)-olefin products with a good functional group tolerance, demonstrating broad applicability. The mechanism involves the in situ formation of a copper complex that binds to the alkyl iodide, leading to radical fragmentation under visible-light irradiation. This process generates alkyl radicals and a persistent copper(II) radical complex, both of which are crucial for subsequent olefin formation. Primary mechanistic studies support the photoinduced cleavage of the C(sp³)–I bond via an inner-sphere electron transfer (ISET) process involving an excited Cu(I) complex associated with the alkyl iodide. Finally, the formation of the M-H product occurs via a base-assisted β-H elimination process.