Sulfone, methyl methylthiomethyl

Methyl methylthiomethyl sulfone and methylthiomethyl p-tosyl sulfone have been monoalkylated, benzylated or alkylsilylated with 1.5 equiv. of the electrophile in the presence of aqueous sodium hydroxide and trioctylmethylammonium chloride (TOMAC). Without doubt the organometallic is less reactive than the one derived from the corresponding sulfoxide since the reaction is rather slow with... 

Methyl Methylthiomethyl Sulfone. Methyl methyl-thiomethyl sulfone is the 5-methyl analog of MT-sulfone and it is conveniently synthesized by oxidation of methyl methylthiomethyl sulfoxide (FAMSO) with potassium permanganate or H202-Na0H. It is useful for synthetic methods similar to those using MT-sulfone synthesis of carboxylic esters, ketones, and a-aLkoxy- -arylacetates. In the reaction of this reagent with allylic bromides, a-methylthio- /,5-unsaturated sulfones are obtained by stirring the bromide with potassium carbonate and potassium iodide in hexamethylphosphoric triamide (eq 14), which does not occur with MT-sulfone. 

Methylthiomethyl p-tolyl sulfone 257 was shown to react with various esters in the presence of excess NaH, affording compounds 263 which, upon reduction with NaBH4 and further treatment with alkali, can be converted to the corresponding aldehydes344. Oxidation of 263 with hydrogen peroxide gives S-methyl a-ketocarbothioates 264335. 

SCH2COOEt) ° and with methyl methylsulfinylmethyl sulfide (MeSCH2SOMe) or methylthiomethyl p-tolyl sulfone (MeSCH2S02C6H4Me) (to give ArCH2-SMe), in each case with a Lewis acid catalyst. 

Protection of carboxyl groups (8, 94). Two new methods for deprotection of methylthiomethyl esters have been reported one involves oxidation to the sulfone followed by alkaline hydrolysis, and the other involves methylation to a sulfonium iodide and hydrolysis. ... 

Synthesis of Esters and Aldehydes. Monoalkylation of methylthiomethyl p-tolyl sulfone (MT-sulfone) with an alkyl halide is achieved by the action of a phase-transfer catalyst (PTC) in toluene-50% aq NaOH. sodium hydride and butyl-lithium also generate a carbanion of MT-sulfone. Arylmethyl derivatives of MT-sulfone are prepared by sodium borohydride reduction of the Knoevenagel condensation products with aromatic aldehydes. The monoalkylated products are converted into the corresponding methyl esters (eq 1). This functionalization can be utilized for synthesizing a-alkoxy carboxylic esters (eq 2) and Q -amino acids (eq 3). ... 

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