Trimethylsulfoxonium iodide

Trimethylsulfoxonium iodide (11) is of interest because treatment with sodium hydride or dimsyl sodium produces dimethyl sulfoxonium methylide [5367-24-8] (12) (eq. 22), which is an excellent reagent for introducing a methylene group into a variety of stmctures (53) ... 

Trimethylsulfoxonium iodide (38 g) is dissolved in deuterium oxide (170 ml) at 80-100° and anhydrous potassium carbonate (50 mg) is added. The mixture is heated on a steam bath for 1 hr, then cooled to 0° for 2 hr before filtering. The recovered solid is re-equilibrated twice more by the same procedure using fresh deuterium oxide. Yield = 33.4 g (88 %). 

To a solution consisting of 1 g (4.6 mmoles) of trimethylsulfoxonium iodide in 20 ml dry dimethyl sulfoxide is added 110 mg (4.6 mmoles) of sodium hydride powder or an equivalent amount of 50 % sodium hydride in mineral... 

Sodium hydride, 50% dispersion in mineral oil Alpha Inorganics Trimethyloxosulfonium iodide (trimethylsulfoxonium iodide) A, EK... 

For the preparation of the benzo[fc]cyclopropa d pyran 2-599, Ohta and coworkers have treated 3-ethoxycarbonylcoumarin (2-597) with dimethylsulfoxonium methylide (2-598), derived from the corresponding trimethylsulfoxonium iodide and NaH (Scheme 2.136) [307]. The isolated product was not 2-599, however, but an unexpected eye lope nia[fc]benzofuran derivative 2-600 probably formed through 2-599. 

Benzo[6]thiophene-2-carbaldehyde can be converted to 2-(l, 2 -epoxyethyl)-benzo[6]-thiophene by reaction with trimethylsulfoxonium iodide and sodium hydride or with diazomethane. However, the 3-carbaldehyde is reported to give the 3-acetyl derivative on treatment with diazomethane (Scheme 120) (70AHC(ll)177). 

The carbamoyl group in position 7 could be transformed by phosphoryl chloride to a nitrile group/4 4-Oxo-4f/-pyrido[l,2-u]pyrimidine-7-carboxy-lic acids were esterified by various methods and the esters cyclized to the tricyclic compounds (279) by treatment with trimethylsulfoxonium iodide in dimethyl sulfoxide in the presence of sodium hydride.60... 

Dimethyloxosulfonium methylide - known as the Corey-Chaykovsky Reagent - is a valuable alternative to dimethylsulfonium methylide and can be generated from trimethylsulfoxonium iodide. 

Preparation. The original procedure (1, 315-318) for the preparation employed reaction of trimethyloxosulfonium iodide with NaH in DMSO. A newer, less hazardous route involves reaction of trimethylsulfoxonium iodide (Aldrich) with potassium /-butoxide in DMSO at room temperature.1... 

With strong bases it is also possible to remove a proton from the methyl group of triarylmethylphosphonium halides, trimethylsulfonium iodide, or trimethylsulfoxonium iodide (Figure 9.1). Here, too, species are produced that are betaines of the ylide type. 

Methylenation of unsaturated sulfoxides 264 using trimethylsulfoxonium iodide and sodium hydride led to the methylene bridged derivative 265 of estradiol (Scheme 68).140 Good stereoselectivity was observed, but it was dependent on the chirality of the sulfoxide moiety. 

Alkylation may take place either on sulfur or on oxygen to form either oxosulfonium or alkoxysulfonium salts. Whereas the former are useful in carbanion chemistry, the latter can be used in oxidizing reactions. If trimethylsulfoxonium iodide is heated with a mild base in deuterium oxide, the hydrogen atoms in the salt are replaced by deuterium. 

Decomposition of the deuteriated trimethylsulfoxonium iodide gives deu-teriated dimethyl sulfoxide and deuteriated methyl iodide. 

A The epoxide can be prepared from cyclohexanone by reaction with the ylide derived from trimethylsulfoxonium iodide or in a... 

Dimethyloxosulfonium Methylide " Deprotonation of trimethylsulfoxonium iodide forms a sulfur ylide that is significantly more stable than dimethylsulfonium methylide and may be prepared and used at room temperature. 

The tricyclic esters 439 were converted to the tetracyclic compounds by treatment with trimethylsulfoxonium iodide in dimethyl sulfoxide in the presence of sodium hydride... 

Methylation of DMSO with methyl iodide yields trimethylsulfoxonium iodide (Scheme 14). This is an unusual reaction since other sulfoxides and halides form the products of O-alkylation. By treatment with strong bases, the trimethylsulfoxonium salt is converted into the sulfoxonium ylide (25) (Scheme 14). 

N-Trim ylsilylacetamide, 1232,1235-1236 Trimethylsilyl azide, 1236 l-Triiiiethylsilyl-l,4-dihydropyridine, 1235 O-Trimethylsilyl ethers, 427 Trimethylsulfonium halides, 314, 315 Trimethylsulfonium iodide, 1236 Trimethylsulfoxonium iodide, 1236... 

The 6-keto group of naltrexone (1) is accessible to nucleophilic attack from the [5-side to provide 6ot-alcohol derivatives. Therefore, we attempted to synthesize a 6a-epoxide derivative 24 of naltrexone with a stable sulfur ylide derived from trimethylsulfoxonium iodide [24]. The 6ot-epoxide 24 was expected to convert to the objective oxabicyclo[2.2.2]octane derivative 20. Instead, the 6 3-epoxide 23 was obtained in 67% yield, but not the objective 6ot-epoxide 24 (Scheme 6). The structure of 23 was determined by X-ray crystallographic analysis (Fig. 8). 

Scheme 6 Reaction of naltrexone methyl ether (22) with a stable sulfur ylide. Reagents and conditions (a) trimethylsulfoxonium iodide, NaH, THF, 55 °C to rt, 67%...

To investigate the source of the unexpected cyclization, we combined a precursor 28 that did not have a 4-hydroxy group with the same stable ylide. This produced compound 29 with an oxabicyclo[2.2.1]heptane skeleton via the epoxide 30. Alternatively, the morphinan methyl ether 28 could also react with the stable sulfur ylide derived from trimethylsulfoxonium iodide at room temperature. The definitive intermediate, 6a-epoxide 30, was isolated, and then treated with NaH in DMF at 80 °C to produce the objective bicyclic compound 29 (Scheme 9). 

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