title: Catalytic asymmetric epoxidation of alpha,beta-unsaturated esters using an yttrium-biphenyldiol complex.
abstract: We succeeded in a catalytic asymmetric epoxidation reaction of alpha,beta-unsaturated esters via a conjugate addition of an oxidant using 2-10 mol % of the yttirium-chiral biphenyldiol catalyst. A variety of substrates with beta-aryl and beta-alkyl substituents were epoxidized efficiently, yielding the corresponding alpha,beta-epoxy esters in up to 97% yield and 99% ee.
authors.affiliation: Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kakei
authors.forename: Riichiro
authors.initials: R
authors.lastname: Tsuji
authors.forename: Takashi
authors.initials: T
authors.lastname: Ohshima
authors.forename: Masakatsu
authors.initials: M
authors.lastname: Shibasaki
mesh_terms: D002384:Catalysis; D004852:Epoxy Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D004952:Esters / Q000138:chemical synthesis* / Q000737:chemistry; D008968:Molecular Conformation; D009942:Organometallic Compounds / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry*; D015019:Yttrium / Q000737:chemistry*
chemical_list: D004852:Epoxy Compounds; D004952:Esters; D009942:Organometallic Compounds; D010636:Phenols; D015019:Yttrium