The Synthesis of Sulfides by Dehydration of Alcohols with Thiol

Abstract

The synthesis of sulfides by the dehydration of various alcohols with n-octanethiol (1) has been investigated.The reactions proceed in the presence of acid catalysts, and the use of Lewis acids as catalysts was usually more effective in the yield of sulfides than protonic acids.The reactivity of butanols was in the order of tertiary > secondary > primary alcohol, but the reaction of (1) with primary alcohol was scarce.The effect of Lewis acids for the reaction of benzylalcohol (2) with (1) was in the order ZnCl2 > SbCl3 > SnCl4 > FeCl3 > AlCl3.The rates of formation of the sulfide and activation energy were measured for the reaction of (2) with (1). The reaction was of the first-order with respect to the concentration of (2) but it was independent of (1). The apparent activation energy was about 26.3 kcal/mol.From the above results, it seems that the formation of carbonium ion takes a rate-determing step in the reaction of (2) with (1).