A short synthesis of (+)-β-lycorane by asymmetric conjugate addition cascade

Abstract

The chiral diether ligand-controlled asymmetric conjugate addition of organolithiums to nona-2,7-dienedioate and subsequent intramolecular conjugate addition of the enolate intermediate gave all-trans trisubstituted cyclohexanes with high ee and yields. Using this methodology, an efficient short asymmetric total synthesis of (+)-β-lycorane was accomplished in 33% overall yield through five steps from the dienedioate.