Co-Catalyzed Reductive Cross-Couplings of Csp³−S with C_allyl−O Electrophiles to form Csp³−Csp³ Bonds

Cross-electrophilic coupling of various benzyl sulfonium salts with C_allyl−O electrophiles is described using a simple Co−Mn catalytic system. This catalytic system is able to activate both the stable Csp³−S bond of sulfonium salts and the Csp³−O bond of allylic acetate or ether under mild reaction conditions to form various functionalized alkyl olefinic compounds. Allyl methyl ethers were employed for the first time in transition metal-catalyzed cross-electrophilic coupling to build Csp³−Csp³ bonds. Preliminary mechanistic studies suggested the involvement of benzyl radicals generated from C−S bond cleavage through a single electron transfer.