In the preparation of propylene sulfide from propylene oxide and thiourea in aqueous solutions the yield of propylene SUI-fide is improved by lowering the pH of the reaction mixture, which cuts down polymer formation. In the presence of an equivalent amount of an acid the reaction between thiourea and an epoxide yields a j3-hydroxythiouronium salt. Generally these salts may be hydrolyzed to yield olefin sulfides or 2-hydroxyalkanethiols ...
