The Reaction of OH Radicals with Dimethyl Sulfoxide. A Comparative Study of Fenton′s Reagent and the Radiolysis of Aqueous Dimethyl Sulfoxide Solutions.

The reaction of OH radicals with dimethyl sulfoxide (DMSO) in aqueous solutions was investigated. The OH radicals were produced via radiolysis of N/sub 2/O saturated aqueous solutions and via Fenton's reagent. With Fenton's reagent the authors observed a quantitative conversion of OH radicals to CH/sub 3/ radicals, giving CH/sub 4/ and C/sub 2/H/sub 6/. The maximum yield in the radiolysis experiments was 86%. In both cases C/sub 2/H/sub 6/ was a major product with the C/sub 2/H/sub 6//CH/sub 4/ ratio as high as 45. The C/sub 2/H/sub 6//CH/sub 4/ ratio depends on the steady-state concentration of CH/sub 3/ radicals and on the DMSO concentration. Results show that CH/sub 3/ radicals in addition to abstracting hydrogen from methanesulfinic acid also abstract hydrogen from DMSO to give CH/sub 4/. In the radiolysis of deuteriated DMSO they observed a much higher ethane/methane ratio than in the nondeuteriated DMSO. The isotope effect supports the hydrogen abstraction from DMSO by CH/sub 3/ radicals. 9 references, 6 tables.