title: Zirconium-mediated intramolecular ester transfer reaction: synthesis of alpha-substituted gamma-aminobutyric acid (GABA) derivatives.
abstract: [reaction: see text]. The zirconium-mediated intramolecular ester transfer reaction of N-alkenyl carbamate derivatives proceeded to give alpha-substituted gamma-aminobutyric acid (GABA) derivatives in good to excellent yields. Quenching experiments of the reaction mixture with iodine or O2 indicated the presence of a cyclopropane intermediate. The resulting iodide was converted to 2-substituted pyrrolidine-3-carboxylate and/or alpha-alkylidene-gamma-aminobutyric acid derivatives in a stereospecific manner.
authors.affiliation: School of Pharmacy, Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
authors.forename: Hisanaka
authors.initials: H
authors.lastname: Ito
authors.forename: Katsunori
authors.initials: K
authors.lastname: Omodera
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Takigawa
authors.forename: Takeo
authors.initials: T
authors.lastname: Taguchi
mesh_terms: D004952:Esters / Q000737:chemistry; D007769:Lactams / Q000737:chemistry; D015040:Zirconium / Q000737:chemistry*; D005680:gamma-Aminobutyric Acid / Q000031:analogs & derivatives* / Q000138:chemical synthesis*
chemical_list: D004952:Esters; D007769:Lactams; D005680:gamma-Aminobutyric Acid; D015040:Zirconium