Copper-Catalyzed Intermolecular Difunctionalization of Styrenes with Thiosulfonates and Arylboronic Acids via a Radical Relay Pathway

A general and practical copper-catalyzed intermolecular difunctionalization strategy of styrenes with methyl thiosulfonates and arylboronic acids has been developed. This method provides an efficient and straightforward avenue to a broad range of 2,2-diarylethyl sulfone derivatives from readily available methyl thiosulfonates and commercially available styrene and arylboronic acid derivatives. The diverse substrate scope attests to the high functional group tolerance of this reaction. The mild nature of this protocol make it suitable for late-stage functionalization of bioactive natural products. Mechanistic investigations support the role of sulfonyl radicals and corroborate a copper-catalyzed radical relay pathway.