Abstract For the first time, fluorinated oxathialones, polyfluoroalkylchlorothioformates, chlorocarbonylpolyfluoroalkylsulfenate esters, a chlorocarbonylhexafluoroisopropylidenimino sulfenate, and a 5-tri-fluoromethyl-2-oxo-1,3,4-oxathiazole were synthesized by reacting chlorocarbonylsulfenyl chloride with RfC(O)CH2C(O)R′ (Rf = CF3; R'= CF3, OC2H5), RfO-Li+ (Rf = CF3CH2, (CF3)2C=N-Li+ and CF3C(O)NH2. Perfluorosuccinic acid and mercury(II) trifluoroacetate with ClC(O)SCI gave their respective anhydrides.