title: Diastereoselective construction of quaternary carbons directed via macrocyclic ring conformation: formal synthesis of (-)-mesembrine.
abstract: In this article, we report a highly diastereoselective new method for the generation of quaternary carbon centers through an anionic oxy-Cope/alkylation sequence where the diastereoselectivity is induced by the conformation of a macrocyclic tetrasubstituted enolate. The use of our methodology culminated in the formal total synthesis of (-)-mesembrine (34) in 11 steps from known starting materials.
authors.affiliation: Department of Chemistry, University of Ottawa, Ottawa, ON, Canada.
authors.forename: Steve
authors.initials: S
authors.lastname: Arns
authors.forename: Marie-Eve
authors.initials: ME
authors.lastname: Lebrun
authors.forename: Christiane M
authors.initials: CM
authors.lastname: Grisé
authors.forename: Irina
authors.initials: I
authors.lastname: Denissova
authors.forename: Louis
authors.initials: L
authors.lastname: Barriault
mesh_terms: D000478:Alkylation; D002244:Carbon / Q000737:chemistry*; D026121:Indole Alkaloids / Q000138:chemical synthesis*; D047028:Macrocyclic Compounds / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D008968:Molecular Conformation; D013237:Stereoisomerism
chemical_list: D026121:Indole Alkaloids; D047028:Macrocyclic Compounds; D002244:Carbon; C011300:mesembrine