Efficient synthesis of 6-membered cyclic monothiocarbonates from halohydrin and carbonyl sulfide.

We report herein an efficient method to synthesize 6-membered cyclic monothiocarbonates which are important intermediates for polymonothiocarbonate synthesis via the cycloaddition of carbonyl sulfide with 1,3-halohydrin using a low-cost base such as triethylamine and potassium carbonate. This protocol features excellent selectivity and efficiency, mild reaction conditions and easy-to-obtain starting materials.