2-Chloro-2'-mercaptodiethyl sulfide (MSM)(I) was synthesized from ethanedithiol and vinyl chloride, and also from 1, 2, 3-0xadithiolane-% oxide (111) with concentrated hydrochloric acid or 2-chloroethyl mercaptan. Its esters were obtained from acylation of I with acid chlorides. 2-Chloro-2'-thioacetoxy diethyl sulfide was also prepared from chlorination of 2- hydroxy-2'-thioacetoxy diethyl sulfide which in turn was obtained from the reaction of 2- ...