Intramolecular alkylation of an alpha-sulfinyl vinylic carbanion without loss of optical purity: a novel access to chiral cyclic vinylic sulfoxides

Novel cyclisation via intramolecular alpha-alkylation of vinylic sulfoxides was studied and cyclic vinylic sulfoxides of various ring sizes (5-7) were synthesised from both (E)- and (Z)-isomers without loss of optical purity.