Trimethyl sulfoxonium iodide

Alkylation of phenoxatellurin with methyl iodide requires heating in a sealed tube to give the corresponding 10-methyltelluronium salt (94). This product is an alkylating agent in its own right and in DMSO solution an equilibrium is established between the salt, phenoxatellurin, and trimethyl-sulfoxonium iodide (95) (Scheme 24) <84JHC413>. 

Homopropargyl cyclohexanone reacts with the S-ylide from trimethyl sulfoxonium iodide in a Corey synthesis (cf p 21). The resulting spiroepoxide A can be subjected to a 5-exo-cyclization catalyzed by titanocene (Cp2TiCl2) in the presence of a stoichiometric amount of Mn yielding a product B in 90% yield. 

Procedure for nucleophilic ring opening of 2,6-diazasemibullvalene 6-la with sulfoxonium ylide Trimethyl sulfoxonium iodide (2.0 mmol, 440 mg) in 2 mL of DMSO was treated with NaH (2.0 mmol, 48 mg), and the reaction mixture was stirred at 85 °C for 1 h and then cooled down. 2,6-Diazasemibullvalene 6-la... 

Trimethyl sulfoxonium iodide (4.0 mmol, 880 mg) in 2 mL of DMSO was treated with NaH (2.0 mmol, 96 mg), and the reaction mixture was stirred at 85 °C for 1 h and then cooled down. 2,6-Diazasemibullvalene 6-la (0.5 mmol, 136 mg) was added, and the reaction mixture was stirred at 85 °C for 24 h. The reaction mixture was quenched with water and extracted with diethyl ether (10 mL) for three times. The combined organic layer was washed with water and brine and dried over MgS04. The solvent was evaporated in vacuum to give yellow oil, which was purified by column chromatography (silica gel, petroleum ether/diethyl ether/triethylamine = 100 1 1) to afford the corresponding product 6-43. 

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