Diastereoselective oxidation of menthyl arenesulfenates to sulfinates and access to enantioenriched aryl methyl sulfoxides

Three aryl methyl sulfoxides were prepared via the following sequence: synthesis of menthyl arenesulfenate from corresponding thiol, diastereoselective oxidation leading to sulfinate, then reaction with a Grignard reagent. The moiety was substituted ester on ortho position or nitro group para position. sulfenate esters obtained in fair excellent yield (42–82%). Four different oxidizing agents tested obtain sulfinate diastereomeric excesses (de) ranging 10 48%. After separation diastereomers and reagent, two enantiopure one enantioenriched sulfoxide (32% ee) obtained.