Transition-metal-free PhI(OAc)2-mediated oxidative S-S and C-N bond formation: Regioselective synthesis of 3H-1,2,4-dithiazol-3-imines

Abstract An effective and new approach is proposed for the synthesis of regioselective 3H-1,2,4-dithiazol-3-imines through S S and C N bond formation for the first time from benzothioamides and isothiocyanates under transition-metal-free conditions. This protocol proceeds by using hypervalent iodine(III) compound of phenyliodine diacetate (PhI(OAc)2) having additive cesium carbonate in acetonitrile solution at room temperature to provide facile access to 3H-1,2,4-dithiazol-3-imine derivatives from readily available starting materials with broad substrate scope, insensitive to air and moisture, regioselectivity and affluent up to gram scale.