Mechanism of the reaction of oxygen atoms, O(3P) with dimethyl disulfide

The mechanism of the reaction of ground state oxygen atoms, O(3P), with CH3SSCH3 was studied by analysis of the final products. Oxygen atoms were generated by mercury photosensitized decomposition of N2O such that [Formula: see text]. The only detected product was CH3S(O)2SCH3, which accounted for close to 70% of the oxygen atoms reacted. Isomerization of small amounts of cis- or trans-2-butene added to the reaction mixture indicated the presence of CH3S radicals. The results are consistent with the primary reaction O + CH3SSCH3 → CH3SO + CH3S. The effect of small amounts of CH3SH and H2S on the yields of CH3S(O)2SCH3 and the products formed provide further information on the nature of the secondary chemistry. A comprehensive reaction mechanism has been proposed.