Cyclohexene episulfide

Phenylthiazirine (40) can be isolated as an intermediate in the photolysis of 5-phenyl-1,2,3,4-thiatriazole and also from other five-membered ring heterocycles capable of losing stable fragments see Scheme 2 (81AHC(28)231). Photolysis of 5-phenylthiatriazole in the presence of cyclohexene yields cyclohexene episulfide (60CB2353) by trapping the sulfur atom. 

Phosgene reacts exothermically with thiirane in two steps (Scheme 36) (77MI50602). 3,5-Dinitrobenzoyl chloride and benzoyl fluoride initiate polymerization of thiirane. A novel reaction of benzoyl isocyanate or trichloroacetyl isocyanate, which yields ethylenethiol derivatives from epithiochlorohydrin (2-chloromethylthiirane), 2-methylthiirane or cyclohexene episulfide, has been reported (Scheme 37) (71BAU2432). 

Photolysis of thiatriazoles was first described by Kirmse,25 who found that aryl cyanides, aryl isothiocyanates, and sulfur are formed on irradition of 5-arylthiatriazoles with UV light. Recently Okazaki et al.n reported the formation of sulfur atoms on irradiation of thiatriazoles. Photolysis of 5-phenylthiatriazole (A lax= 280 nm, e — 10800)25 in the presence of cyclohexene yielded cyclohexene episulfide. Cyclohexene thiols were not formed this was taken as an indication that the reactive species is a triplet sulfur atom. Tetramethylethylene behaves similarly.22... 

The potential use of the reaction was examined, but the episulfides decompose partially during the process, and the yield of cyclohexene episulfide under optimum conditions was 20%. Since episulfides may be obtained in much higher yields from the photodecomposition of COS to give triplet sulfur atoms in gas-phase reactions,26 the method hardly has synthetic importance. It was assumed that the low yield is due to deactivation of the sulfur atoms by collision with solvent molecules, causing them to polymerize to molecular sulfur instead of reacting with cyclohexene.22... 

Johnson and Taylor have shown that for the first tune episulfones may be prepared by oxidation of a variety of the corresponding mono- and bi-cyclic episulfides using oxone-trifluoroacetone, although r/. v-stilbene and cyclohexene episulfides failed.197 Preliminary mechanistic studies indicated that neither TFDO or Oxone alone was the... 

Two new methods for thiirane reduction have been described. The first entails reduction with lithium(0) in refluxing DME <84iJC(B)879>. Both cyclohexene episulfide and cyclohexene oxide are cleanly converted to cyclohexene under these conditions, and both cis- and //wM-2,3-diphenyl-thiirane (or a mixture of isomers) gave only franj-stilbene. An explanation for the latter result was not stated. Cyclohexene was also formed quantitatively by treatment of cyclohexene sulfide with... 

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