Visible-Light-Driven Palladium-Catalyzed Oxy-Alkylation of 2-(1-Arylvinyl)anilines by Unactivated Alkyl Bromides and CO2: Multicomponent Reactions toward 1,4-Dihydro-2H-3,1-benzoxazin-2-ones.

A visible-light-driven palladium-catalyzed radical oxy-alkylation of 2-(1-arylvinyl)anilines with unactivated alkyl bromides and CO2 has been developed toward 1,4-dihydro-2H-3,1-benzoxazin-2-ones. This multicomponent reaction (MCR) starts with (1) carboxylation of an amino by CO2; (2) formation of Pd(I) and an alkyl radical via visible-light-driven reaction of alkyl bromides and Pd(0); (3) addition of an alkyl radical to the vinyl followed by single electron transfer (SET) oxidation to the carbocation by Pd(I); and (4) cyclization via intramolecular nucleophilic attack of the carboxylate anion to carbocation.