Dibenzyl sulphide

The oldest and generally applied sulphoxide synthesis consists of the oxidation of sulphides to sulphoxides. This reaction was reported for the first time by Marcker9 as early as 1865. He found that treatment of dibenzyl sulphide with nitric acid afforded the corresponding dibenzyl sulphoxide in a high yield. Since that time the oxidation of... 

Sulphides are quickly and efficiently converted into sulphoxides by 1-chlorobenzo-triazole (NCBT) in methanol at —78°106. However, this. reagent cannot be used for the oxidation of t-butyl sulphide and dibenzyl sulphide since C—S bond cleavage takes place. 

Silica gel supported sodium metaperiodate was used for the selective oxidation of dibenzyl sulphide . Metaperiodate anion soaked on strongly basic-ion-exchange resins Amberlite IRA-904 or Amberlyst A-26 was found to be able to oxidize sulphides into the corresponding sulphoxides in 82-99% yield ... 

Thioamides are converted into 5-benzyl salts under basic catalysed conditions. The unstable salts spontaneously eliminate benzylthiol to yield nitriles (>80%) [47] the benzylthiol is benzylated during the reaction and is isolated as dibenzyl sulphide. 

Dibenzyl sulphide [528-74-9] M 214.3, m 48.5 . Crystd from EtOH/water (10 1), or repeatedly from purified hot ethyl ether. Vacuum dried at 30 over P2O5, fused under nitrogen and re-dried. 

Cognate preparation. Dibenzyl sulphide. Heat a solution of 63 g (0.5 mol) of benzyl chloride in 160 ml of rectified spirit on a steam bath and stir while... 

Stir 2.35 g (0.011 mol) of sodium metaperiodate (Section 4.2.55, p. 454) in 45 ml of a 1 1 mixture of water and methanol held at 0°C. Add portionwise 2.14 g (0.01 mol) of dibenzyl sulphide (Expt 5.204) and continue to stir the mixture at 0 °C for several hours, preferably overnight. Extract the reaction mixture (which contains precipitated sodium iodate) with three 20 ml portions of chloroform. Dry the combined chloroform extracts over magnesium sulphate and remove the solvent on a rotary evaporator. Recrystallise the product from ethanol. The yield of dibenzyl sulphoxide is 2.2 g (96%), m.p. 135 °C. 

The radicals CXC were formed from CXCVIIa also by oxidation with oxygen bonded to Co(II)acetylacetonate22. This results from the electron density distribution in dibenzyl sulphide CXCVIIa, which behaves as an alkylsubstituted mononuclear phenol. 

Further studies of carbene insertion into the C S bond are reported, the authors earlier work on alkyl allyl sulphides, using bis(methoxy-carbonyl)carbene, now being supplemented by a study of the relative tendencies towards C—S insertion and C=C addition for the same substrates with carbethoxycarbene (from ethyl diazoacetate). 1,2-Diphenyl-ethyl phenyl sulphide, PhCH(CHaPh)SPh, is formed by the action of benzyne on dibenzyl sulphide, via the sulphonium ylide. Alkylation at sulphur is one of the best-known reactions of sulphides, and novel syntheses of this type have been reported in which the formation of hydro-quinone sulphonium salts, from quinone and a sulphide in 70% H2SO4 at — 5 to -f 5 and Markownikov addition of a sulphide to an alkene under similar conditions are discussed. 

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