Formation of dimethyl sulfide

The formation of dimethyl sulfide, dimethyl sulfone, and methane (by H-abstraction) observed in these photolyses is thus accounted for. Hydrogen abstraction by the methylsulfinyl radical affords methanesulfenic acid, CH3SOH, a very reactive molecule, which rapidly undergoes a series of secondary reactions to produce the methanesulfonic acid, methyl methanethiolsulfonate (CH3S02SCH3), and dimethyl disulfide which were also observed during these photolyses. 

Thus, among the sulfur amino acids, hydrogen sulfide is a likely derivative of cysteine, and dimethyl disulfide is a likely derivative of cystine. The formation of dimethyl sulfide and dimethyl disulfide from methionine is readily deduced from expected recombinations of thiomethyl and methyl free radicals. Dimethyl disulfide is the major product. 

Silva Ferreira, A. C., Rodrigues, P., Hogg, T., and Guedes de Pinho, P. (2003a). Influence of some technological parameters on the formation of dimethyl sulfide, 2-mercaptoethanol, methionol, and dimethyl sulfone in Port wines. ]. Agric. Food Chem. 51, 727-732. 

Kiene R. P. and Hines M. E. (1995) Microbial formation of dimethyl sulfide in anoxic Sphagnum peat. Appl. Environ. Microbiol. 61, 2720-2726. 

Dystra, G.J., 1971. Formation of dimethyl sulfide by Propionibacterium shermanii ATCC 9617. J. Dairy Sci., 54 168—172. 

Because sulfoxide sulfur is in an intermediate oxidation state, formally -1-4, it undergoes a small degree of thermal disproportionation to the corresponding sulfone and sulfide, at elevated temperatures near or above the normal boiling point. The formation of dimethyl sulfide is in part responsible for the garlic-like odor in aged DMSO, and can be minimized by storage under air. 

Granroth, B. and Hattula, T., 1976. Formation of dimethyl sulfide by brackish water algae and its possible implication for the flavor of Baltic herring. Finn. Chem. Lett., 6 148-150. 

Hattula, T. and Granroth, B., 1974. Formation of dimethyl sulfide from S-methyl-methionine in onion seedlings (Allium cepa). J. Sci. Food Agric., 25 1517—1521. 

Tokunaga, T., 1977. Formation of dimethyl sulfide in Antarctic krill, Euphausia superba. Nihon suisan-gakkai shi, 43 1209—1217. 

Figure 8,59 Formation of dimethyl sulfide from S-methyl methionine.

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