Dissolved in 20 ml of methylene chloride was 2.99 g of 4-(3-ethoxy-2-hydroxypropoxy)phenylcarbamoylmethyl methyl sulfide. To the solution was added 5.50 g of methyl p-toluenesulfonate. The mixture was stirred at room temperature for 24 hours and ether was added to the reaction mixture. The insoluble solid was filtered off and recrystallized from methylene chloride-ether, giving 4.75 g of 4-(3-ethoxy-2-hydroxypropoxy)phenylcarbamoylmethyldimethylsulfonium p-toluenesulfonate (Compound 1) in 97.7% yield, M.P. 139° to 141° C.
