A new catalytic method for the chemoselective oxidation of sulfides to the sulfoxides has been studied. A variety of dialkyl, alkylaryl and diaryl sulfides were subjected to the oxidation reaction by a mixture of nitro urea, derived from urea nitrate, silica sulfuric acid (SiO2-OSO3H) and catalytic amounts of ammonium bromide in CH2Cl2 at room temperature.
