Photoredox-catalyzed multicomponent transformation towards functionalized trans-2,3-disubstituted indolines

Abstract

We report a visible light photoredox-catalyzed multi-component reaction (MCR) of N-substituted 2-vinyl anilines, diaryliodonium triflates, and sulfonium/sulfoxonium ylides for the efficient synthesis of a diverse range of functionalized trans-2,3-disubstituted indolines in good to excellent yields. While the MCR involving sulfonium ylides is catalyzed by Ru(bpy)₃Cl₂·6H₂O, the MCR with sulfoxonium ylides can be carried out using inexpensive organic dye fluorescein. Control experiments unequivocally establish the intermediacy of radicals derived from both diaryliodonium triflates and sulfonium/sulfoxonium ylides. The redox-neutral process displays a broad substrate scope, high structural diversity, and proceeds under amenable conditions.