Chlorine in oxidation of methyl disulfide

Cadmium chloride as catalyst in conversion of dipotassium 1,8-naph-thalenedicarboxylate to 2,6-naph-thalenedicarboxylic acid, 72 Chlorination, nuclear, aluminum chloride as catalyst for, 9 of pyruvic acid by sulfuryl chloride, 54 Chlorine in oxidation of methyl disulfide to methanesulfinyl chloride, 62 3-Chloroacetophenone from aluminum chloride catalyzed chlorination of acetophenone, 10... 

Hydroxy-[l,2,4]triazolo[4,3-fl]pyridine (91) was reluctant to react with the common hydroxylic chlorinating agents, giving at best, the 3-chloro compound in only 15% yield with pWphorus oxychloride-dimethylaniline. Methylation of (91) produced 2-methyl-[l,2,4]triazolo[4,3-n]pyrid-3-one (92) whereas methylation of the 3-thiol (93) resulted in methyl [l,2,4]triazolo[4,3-a]pyrid-3-yl sulfide (94), a molecule also resistant to nucleophilic substitution (66JOC265). Potassium ferricyanide oxidation of (93) resulted in the corresponding disulfide. 

Methanesulfonic acid is primarily manufactured by the batch or continuous oxidation of the methyl mercaptan or dimethyl disulfide with chlorine in saturated aqueous hydrochloric acidJ This chemistry is also the basis for much of the worldwide production of MSC, with photochlorination of methane (vide infra) being the most significant commercial alternative. Other alkanesulfonyl chlorides and sulfonic acids have also been produced in lesser quantities by the CI2/H2O oxidation. Reaction yields are typically 92-100%. The HCl by-product separates as vapor from the saturated reaction mixture. It is absorbed into water to afford a... 

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