Catalytic Oxidation of Sulfides to Sulfoxides by Poly(4-vinyl pyridinium nitrate), Silica Sulfuric A

A new catalytic procedure for the chemoselective oxidation of sulfides to sulfoxides was studied. A variety of aliphatic and aromatic sulfldes were subjected to sulfoxidation by combining poly(4-vinyl pyridinium nitrate), silica sulfuric acid (SiO2-OSO3H), and catalytic amounts of ammonium bromide in CH2Cl2 in the presence of a few drops of water at room temperature. Excellent yields were obtained.