Sulphenyl sulphinates

Ab initio MO calculations at the 6-31G level verify these conclusions and reveal that (i) disproportionation of arenesulphinyl radicals to arenesulphonyl and arenethiyl radicals is exothermic by —13.6kcalmol-1 and (ii) that the sulphenyl sulphinate structure 57 is 28kcalmol 1 more stable than the wc-disulphoxide 58108. 

Dithietans.—1,2-Dithietan (114) is the first isolated derivative in that class. It arises by dimerization of ethyl sulphine, probably by rearrangement of a first-formed sulphenyl sulphinate (see Chap. 3, Pt. II, p. 161). 

Unsymmetrical thiosulphinates and thiosulphonates are both oxidized by potassium superoxide in pyridine in the presence of 18-crown-6 ether to produce sulphinic and sulphonic acids and a disulphide, under mild conditions (equation 84)200,201. Sulphinic and sulphonic acids were produced from both the R and R substituents whilst the disulphide was derived only from the sulphenyl side of the reactant. Thus, the reaction mixture contained five products, making the reaction not synthetically useful. Pyrolysis of thiosulphinates also produces mixtures of products, one being the thiosulphonate again this is not a synthetically useful reaction202. 

Reactions of arenesulphenyl chlorides with hydroxyl functions of nucleosides have been investigated with N phthalimido-2, 3 -0-isopropylideneadenosine, o-nitrophenyl sulphenyl chloride gave the 5 -0-sulphenyl ester, whilst other sulphenyl chlorides without an o-nitro group gave mixtures of sulphinate esters and 5 -deoxy-5 -chloro compound. Mechanisms were suggested. ... 

Disproportionation of sulphenic adds has also been suggested as a possible route for the formation of these compounds (equation 24). The hydrolysis of sulphenyl halides under not carefully controlled conditions and particularly in concentrated solutions lead to disulphides and thiolsulphonates because of the easy disproportionation of thiol-sulphinates (equation 25). 

References to addition reactions of sulphenyl halides with alkenes and alkynes are given in the Sulphides section. An incidental bonus from a study of the addition of PhSCl to adamantylideneadamantane is the formation of the 4e-chloro-derivative and PhSSPh, via an intermediate thiiranium salt. Sulphenyl and selenenyl chlorides have been used for the dehydration of aldoximes to nitriles. Whereas sulphinyl chlorides yield sulphinate esters with alkoxytri-methylsilanes, no reaction occurs with sulphenyl chlorides. ... 

Change of personnel has led to the division of the wide-ranging chapters on thiocarbonyl compounds and on ylides into more manageable parts. In keeping with more recent work, the short sections on sulphines and sulphenes have been confined to the chapter on thiocarbonyl compounds. To avoid possible inconsistencies, the chemistry of sulphonyl, sulphinyl, and sulphenyl carbanions has been largely included in the chapter on ylides. The order of the chapters has been revised so that the chemistry of acyclic sulphur compounds and sulphur-containing functional groups is covered before cyclic systems. 

Adducts (186) were formed by the regiospecific, but nonstereospecific, reaction of diphenylnitrilimine with diaryl sulphines." Sulphines of the type (187) reacted with aromatic sulphenyl chlopdes in a thiophilic manner, yielding (188). The sulphenic acid (189), a tautomer of (187), was considered as the reactive species in the latter reaction. The nucleophilic attack of azide ions on thiobenzoyl chloride S-oxide gave the yellow, very unstable sulphine (190), which decomposed rapidly to ben-zonitrile at room temperature with the evolution of gas, but which at -80 C could be characterized by means of i.r. spectroscopy. 9-Thiofluorenone... 

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