The synthesis of tertiary thiols in enantiomerically enriched form is accomplished by lithiation of enantiomerically enriched N-aryl allylic thiocarbamates. Formation of an allyllithium derivative promotes intramolecular N to C aryl migration to the position α to sulfur, generally with good stereospecificity. The substrates may themselves be obtained by Pd-catalyzed enantioselective [3,3]-sigmatropic rearrangement of N-aryl O-allyl thiocarbamates. Solvolysis of the product thiocarbamates yields tertiary thiols, which may be converted to sulfide derivatives.

Stereospecific [3,3]-sigmatropic rearrangement of O-substituted thiocarbamate derivatives of enantiopure allylic alcohols provides allylic thiocarbamates as single enantiomers. Intramolecular arylation by rearrangement of their allyllithium derivatives provides allylic tertiary thiols. Allylation and ring-closing metathesis gives 2,5-dihydrothiophenes containing sulfur-bearing quaternary centres.

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Thiocarbonylimidazole (II) reacts with allylic alcohols to generate intermediate esters of type (III) which rearrange spontaneously in situ to yield S‐allyl imidazolyl thiol esters (IV).

The reaction of alcohol (I) with N,N′‐thiocarbonyldiimidazole is accompanied by a [3,4]‐sigmatropic rearrangement to afford imidazoles (III), which are readily converted into thiocarbamates (V).