Asymmetric Synthesis of (2R,5S,7R)-2,7-Dimethyl-1,6-dioxaspirononane

Article abstract of DOI:10.1021/jo00121a015

A short enantioselective synthesis of (2R,5S,7R)-2,7-dimethyl-1,6-dioxaspiro<4.4>nonane is described via an enantioselective synthesis of (2S,8S,SR)-2,8-dihydroxy-5-(1,3-dioxolanyl)-1,9-(p-tolylsulfinyl)nonane by stereoselective reduction of the corresponding diketo disulfoxide.The formation of the spiro carbon was stereocontrolled during a cyclization carried out under equilibrating conditions in the presence of ZnBr2.