Tertiary Thiols from Allylic Thiocarbamates by Tandem Enantioselective [3,3]-Sigmatropic Rearrangement and Stereospecific Arylation

Abstract

The synthesis of tertiary thiols in enantiomerically enriched form is accomplished by lithiation of enantiomerically enriched <i>N</i>-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 <i>N</i>-aryl <i>O</i>-allyl thiocarbamates. Solvolysis of the product thiocarbamates yields tertiary thiols, which may be converted to sulfide derivatives