An alcohol thioetherification method utilizing a domino dual catalysis strategy

Abstract

Thioethers are prevalent in pharmaceuticals, and its synthetic method utilizing alcohols are receiving more attention due to its environmental benign property. Here, a metal-free dehydrative thioetherification method was reported, enabling the conversion of various alcohols into thioethers via a domino dual catalysis strategy including catalyzed Mitsunobu reaction and followed nucleophilic substitution. Although this method cannot provide satisfactory yields for certain alcohols, it improves the substrate scope of alcohol thioetherification to general primary and secondary alcohols. By employing phosphine oxide and triflic acid as catalysts, 16 phenyl thioethers were synthesized with low to moderate yields via the Dean-Stark distillation. Moreover, the above results indicate that the yield and substrate scope of this method could be enhanced by improving the catalytic rate of the phosphine oxide.