Catalytic asymmetric synthesis of new halogenated chiral synthons

Two-step and practical asymmetric syntheses of enantiomerically pure 4-trifluoromethyl-2,2-dioxo-1,3,2-dioxathiolane and 4-trichloromethyl-2,2-dioxo-1,3,2-dioxathiolane (>98% ee) have been achieved. Catalytic asymmetric dihydroxylation (AD) of 3,3,3-trifluoropropene and 3,3,3-trichloropropene, respectively, is followed by direct cyclic sulfate formation by reaction with sulfuryl chloride. Opening of the cyclic sulfates with various nucleophiles provides easy access to important chiral synthons.