Synthesis of Thioethers via Nickel-Catalyzed Cross-Coupling of Aryl Halides with Ketene Dithioacetal

Herein, we present a nickel-catalyzed C-S cross-coupling between aryl halides and ketene dithioacetals under "base-free" conditions without an exogenous ligand. By employing easily available ketene dithioacetals as sulfide donors, this reaction affords a broad range of unsymmetrical alkyl-aryl sulfides without using odorous and toxic thiols. The newly developed catalytic methodology features an excellent functional group tolerance, wide substrate scope, and diverse downstream synthesis. Preliminary mechanism investigations reveal that a Ni(I)/Ni(III) catalytic cycle might be involved.