title: Highly stereoselective epoxidation of alpha-methyl-gamma-hydroxy-alpha,beta-unsaturated esters: rationalization and synthetic applications.
abstract: The diastereoselectivity of the nucleophilic epoxidation of gamma-hydroxy-alpha,beta-unsaturated esters having a methyl substituent at the alpha- or beta-position was investigated. Epoxidation of the alpha-methyl-substituted enoate was highly stereoselective, giving rise to the syn isomer. This finding was used to perform an enantioselective synthesis of a natural product having a beta-hydroxy-alpha-methylene-gamma-butyrolactone motif. The nucleophilic epoxidation of enoates was found to be irreversible. Models to explain the observed stereoselectivities are proposed.
authors.affiliation: Departament de Química Inorgànica i Orgànica Universitat Jaume I, 12080 Castelló, Spain.
authors.forename: Irakusne
authors.initials: I
authors.lastname: López
authors.forename: Santiago
authors.initials: S
authors.lastname: Rodríguez
authors.forename: Javier
authors.initials: J
authors.lastname: Izquierdo
authors.forename: Florenci V
authors.initials: FV
authors.lastname: González
mesh_terms: D004852:Epoxy Compounds / Q000737:chemistry*; D004952:Esters / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D013055:Spectrophotometry, Infrared; D013237:Stereoisomerism
chemical_list: D004852:Epoxy Compounds; D004952:Esters