Carbodithioic acids react with trivalent sulphur compounds bearing semipolar linkages (sulphoxides, sulphonium ylides and sulphilimines), to give the corresponding sulphides and add to olefins to afford dithioesters. The orientation of olefin addition is controlled by the olefin nature. Michael type addition takes place with olefins bearing an electron-withdrawing group α to the double bond while Markownikoff addition occurs with olefins bearing an ...