Efficient deoxygenation of sulfoxides to thioethers and reductive coupling of sulfonyl chlorides to disulfides with tungsten hexachloride

Tungsten hexachloride (WCl6) in the presence of NaI in anhydrous acetonitrile or zinc powder in anhydrous THF converts sulfoxides to their thioethers in high yields. Reductive coupling of sulfonyl chlorides to their corresponding disulfides is also achieved efficiently with the above reagent in anhydrous acetonitrile in high yields. Sodium benzene sulfinate as a model compound for sulfinate salts is also converted to diphenyl disulfide in almost quantitative yield.