Arylmethyl sulfoxides

Bordwell and Boutan (BB)81 carried out extensive work on the methylsulfmyl group in 1957. It must be emphasized that they found that the preparation of pure arylmethyl sulfoxides from arylmethyl sulfides by oxidation was not a trivial matter. The frequently recommended reagent, hydrogen peroxide in acetic acid, tended to give sulfoxides contaminated with appreciable quantities of sulfones, which could not be removed by fractional crystallization. Oxidation by nitric acid was found to be more satisfactory. 

Modest and good selectivity have also been obtained for the preparation of arylmethyl sulfoxides using titanium(IV) tetraisopropoxide modified with R-( + )-binaphthol and TBHP. As with other related systems, the addition of water is of crucial importance for good selectivity (Figure 3.102).410... 

The kinetics of chlorination of arylmethyl and arylisopropyl sulfoxides with CBT in acetonitrile in the presence of pyridine show the reaction... 

The enantioselectivities of the sulfoxidation of arylmethyl sulfides and t-butylmethyl sulfide with H2O2 are improved by making structural changes to the planar chiral fiavinium catalysts such optimization led to enantioselectivities of up to 61% ee for aromatic sulfides and of up to 65% ee for t-butyl methyl sulfide. " (S)... 

---