Convenient Synthesis of α-Hetero-Substituted Acyloxathianes

Article abstract of DOI:10.1021/jo00045a031

In contrast to simple esters, α-alkoxy, α-alkylthio, and α-dimethylamino esters react with lithiooxathiane 1-Li in good yield to give the corresponding α-functionalized 2-acetylhexahydro-4,4,7-trimethyl-4H-1,3-benzoxathiin 2.In some cases, mixtures of diastereomers (2, 2') are obtained.The reaction has been extended to α-methoxy- and α-<(triisopropylsilyl)oxy>propanoyl and α-(methylthio)butanoyl homologs which have chiral centers at C(α).