title: Hydroxylated pyrrolidines. Enantiospecific synthesis of all-cis 2,3,4,5-substituted pyrrolidine derivatives from serine.
abstract: We report the enantiospecific synthesis of the sterically congested all-cis 2,3,4,5-substituted pyrrolidines 4, 5, and 6, from either D- or L-serine. Hemiaminal intermediate 13 is converted to the fully substituted pyrrolidine 15 by way of a tandem Wittig-Michael reaction. The endo stereochemistry of the C-3 methyl group of compound 15 is set by stereoselective reduction of the double bond in 11, driven by a preference for hydrogenation from the rear side of the molecule. The all-cis configuration of these fully substituted pyrrolidines has been established by X-ray analysis of compound 6. Removal of the benzenesulfonyl group from the highly substituted and functionalized intermediate 15 is successfully accomplished by sodium naphthalenide reduction.
authors.affiliation: Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, USA.
authors.forename: Sharad K
authors.initials: SK
authors.lastname: Verma
authors.forename: M Nieves
authors.initials: MN
authors.lastname: Atanes
authors.forename: J Hector
authors.initials: JH
authors.lastname: Busto
authors.forename: Dung L
authors.initials: DL
authors.lastname: Thai
authors.forename: Henry
authors.initials: H
authors.lastname: Rapoport
mesh_terms: D002384:Catalysis; D018360:Crystallography, X-Ray; D008968:Molecular Conformation; D015394:Molecular Structure; D011759:Pyrrolidines / Q000138:chemical synthesis* / Q000737:chemistry; D012694:Serine / Q000031:analogs & derivatives* / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D011759:Pyrrolidines; D012694:Serine