A general and efficient method for the selective synthesis of β-hydroxy sulfides and β-hydroxy sulfoxides catalyzed by gallium(III) triflate

Gallium(III) triflate-catalyzed ring opening of epoxides affords beta-hydroxy sulfides with high regioselectivity and chemoselectivity in high yields (84-97%) under solvent-free conditions. Additionally, a simple, efficient, and environmentally benign one-pot procedure for the synthesis of beta-hydroxy sulfoxides in sole water has been developed for the first time. The process, promoted by a H2O2-Ga(OTf)(3) system, affords beta-hydroxy sulfoxides in high yields (81-94%) and high chemoselectivity without any detectable overoxidation to beta-hydroxy sulfones. The catalyst could be recovered easily after the reactions and reused without evident loss of activity.