Copper-Catalyzed Radical Decarboxylative Alkylazolation and Alkylcyanation of Vinylarenes with Alkyl Diacyl Peroxides

A novel copper-catalyzed three-component radical decarboxylative alkylazolation and alkylcyanation of vinylarenes have been developed. The strategy utilizes readily available alkyl diacyl peroxides as both radical sources and alkylation reagents, wherein alkyl radicals are generated via sequential single electron transfer (SET) and decarboxylation. The resulting carbon-centered radicals subsequently undergo radical addition to alkenes, followed by copper-catalyzed C(sp3)-C(sp2) or C(sp3)-C(sp) cross-coupling with trimethylsilyl azoles or trimethylsilyl cyanide (TMSCN), respectively. This method provides an efficient approach to access various azole and nitrile derivatives, with the latter easily converted to amide, carboxylic acid, and ester derivatives. The protocol features exclusive chemo- and regioselectivity, a broad substrate scope, and good functional group tolerance under mild reaction conditions. Mechanistic studies demonstrated the involvement of alkyl radical species and supported a radical process for this dicarbofunctionalization.