Sulfone, dibenzyl

Ci4Hi402S, Dibenzyl sulfone c15h14o2s, cis-Styryl p-tolyl sulfone [(Z)-1 -Methyl-4-(2-phenylethenyl)sulfonylbenzene] c15HI4o2s, frans-Styryl p-tolyl sulfone [( )-l-Methyl-4-(2-phenylethenyl)sulfonylbenzene] C12H10O4S2, Diphenyl disulfone... 

Both the a- and a -hydrogens of dibenzyl sulfone were shown to be ionized by means of two equivalents of potassium amide in liquid ammonia322. 

Remarkable solvent effects on the selective bond cleavage are observed in the reductive elimination of cis-stilbene episulfone by complex metal hydrides. When diethyl ether or [bis(2-methoxyethyl)]ether is used as the solvent, dibenzyl sulfone is formed along with cis-stilbene. However, no dibenzyl sulfone is produced when cis-stilbene episulfone is treated with lithium aluminum hydride in tetrahydrofuran at room temperature (equation 42). Elimination of phenylsulfonyl group by tri-n-butyltin hydride proceeds by a radical chain mechanism (equations 43 and 44). 

C14H14O2S, Dibenzyl sulfone C.5H14O2S, ds-Styryl p-tolyl sulfone... 

We consider first how surfaces which are themselves not photosensitive can perturb chemical reactivity. First, the surface can influence diffusional motion of adsorbed substrates, intermediates or products. With preadsorbed substrates, one can probe the nature of motion of intermediates generated on the surface and search for differences in reactivity caused by surface confinement . When several photochemical precursors to benzyl radicals, e.g., benzyl phenylacetate, a dibenzyl ketone, or a dibenzyl sulfone, are irradiated as adsorbates on dry silica gel, singlet and triplet radical pairs are generated, Eq. (7). The extent of radical recombination observed requires... 

The sulfonyl group is a key feature in the preparation of the unusually substituted dithiin sulfone (174) from dibenzyl sulfone. The acidic a-protons are abstracted with sodium hydride and the carbanionic intermediates react with carbon disulfide. The reaction is quenched with methyl iodide to give (174) in 17% yield (73BSF637). Another multisubstituted dithiin (175) is available from the reaction of diphenylthiirene dioxide with the ylide (176) (Scheme 21) but again the yield is low. However, the reaction is of particular interest in so far as the product mixture also contains a derivative of the rare oxathiin nucleus. Indeed of the three products isolated the oxathiin sulfone (177) is formed in marginally the highest yield (73BCJ667). 

Keywords sodium dithionite, sodium formaldehyde sulfoxylate, benzyl halide, dibenzyl sulfone... 

Benzyl bromide (17.1 g, 0.1 mol) was added to a mixture of solid sodium dithionite (10.44 g, 0.06 mol) and Aliquat 336 (1.2 g, 0.03 mol). The mixture was vigorously shaken for 5 min and then heated in an oil bath for 20 h at 120 °C. Dibenzyl sulfone was removed by filtration through Florisil with 50 mL of methylene chloride. The solvent was evaporated and the crude solid crystallized from a 1 1 mixture of ethanol and toluene to give the pure sulfone as a white solid (7.54 g, 61%), mp 148-149 °C. 

An analogous procedure was carried out with benzyl bromide (17.1 g, 0.1 mol), sodium formaldehyde sulfoxylate dihydrate (10.35 g, 0.06 mol) and sodium carbonate (10.35 g, 0.075 mol) to obtain the pure dibenzyl sulfone (9.35 g, 76% after recrystallization). 

The hydrogenolysis of sulfones and sulfonic acids over MoS3 requires higher temperatures (300-375°C) than for thiols, sulfides, or disulfides, except with dibenzyl sulfone, where hydrogenolysis to give toluene proceeded at 200-250°C. / -Tolu-... 

C14H1402S dibenzyl sulfone 620-32-6 25.00 1.1737 2 27318 C14H16BrN 1-phenethyl-2-picolinium bromide 10551-21-0 25.00 1.2868 2... 

Sulfones undergo peculiar reactions on treatment with carbon tetrachloride and potassium hydroxide in aqueous rm-butyl alcohol at 25-80 °C. Methyl phenyl sulfone yields phenyl trichloromethyl sulfone, which is hydrolyzed to benzenesulfonic acid [954. Dibenzyl sulfone is quantitatively converted into fran -stilbene, and dicyclohexyl sulfone is converted into a mixture of bicyclohexylidene and l,l-dichloro-2,3-dicyclohexylcy-clopropane [954] (equations 582-584). 

The reaction was carried out on numerous aromatic and aliphatic sulfides and sulfoxides. Among the compounds made in essentially quantitative yields were dibenzyl sulfoxide, dibenzyl sulfone, dimethyl sulfone, diphenyl sulfoxide, thionyldiglycolic acid, and carboxymethylthionylsuccinic acid (Table I). 

Meyers method has been modified to allow it to be operated under phase-transfer conditions.This is a convenient way of converting dibenzyl sulfones directly into ( )-stilbenes (equation S), but it is not so useful for less reactive substrates. 

Cyclobutenes prepared by the Ramberg-BScklund reaction are almost always unsubstituted at the vinylic positions. In 1974, Paquette introduced a related and complementary ring contraction which is particularly suitable for the synthesis of 1,2-dialkylcyclobutenes. The reaction takes place when carbanions of five-membered cyclic sulfones are treated with LAH in refluxing dioxane (Scheme 19). The mechanism of the reaction is not clear. Good yields are obtained only when the sulfone is 2,5-dial-kylated in the absence of these groups, simple reduction of sulfone to sulfide becomes a serious side reaction. Dibenzyl sulfone is converted into a mixture of stereoisomeric stilbenes (56%) and dibenzyl sulfide (23%) under the same conditions. ... 

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