Trimethylsulphoxonium iodide

To a suspension of sodium hydride (1.2g, 0.05 mol) in dimethylformamide (100 ml) is added in one portion solid trimethylsulphoxonium iodide (11.05 g, 0.052 mol) (1). An exothermic reaction takes place with copious evolution of hydrogen. After all the hydrogen has been evolved (5 minutes), the mixture is stirred for another 15 minutes, and ethyl crotonate (5.7 g, 0.05 mol) in dimethylformamide (15 ml) is added to the methylide in one portion. An exothermic reaction takes place and the mixture turns slightly yellow. Stirring is continued for another hour. The mixture is poured into hydrochloric acid-ice-water (100 ml, 3%), extracted with ether (3 x 50 ml), the ether extract... 

When benenethiol reacts with trimethylsulphoxonium iodide in dimethylformamide at 100°C, phenyl methyl sulphide, diphenyl disulphide and dimethyl sulphide are formed. ... 

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