Copper-Catalyzed Radical Alkyl- and Aminosulfinylation of Styrenes Enabled by β-Sulfonyl Sulfoxides as Sulfenate Anion Precursors.

Sulfenate anions are powerful but labile intermediates for sulfoxide synthesis, and their generation under harsh conditions has limited their use in radical chemistry. Here, bench-stable β-sulfonyl sulfoxides are introduced as readily accessible sulfenate precursors that release sulfenates under mild conditions. This platform enables copper-catalyzed three-component 1,2-alkylsulfinylation and 1,2-aminosulfinylation of styrenes with a broad scope, late-stage applicability, and mechanistic evidence for radical-anion crossover.