title: Catalytic asymmetric synthesis of 2,2-disubstituted terminal epoxides via dimethyloxosulfonium methylide addition to ketones.
abstract: Catalytic asymmetric Corey-Chaykovsky epoxidation of ketones with dimethyloxosulfonium methylide 2 using an LLB 1a + Ar3P O complex proceeded smoothly at room temperature, and 2,2-disubstituted terminal epoxides were obtained in high enantioselectivity (91-97%) and yield (>88-99%) from a broad range of methyl ketones with 1-5 mol % catalyst loading. The use of achiral additive Ar3P O 5i was important to achieve high enantioselectivity.
authors.affiliation: Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Sone
authors.forename: Akitake
authors.initials: A
authors.lastname: Yamaguchi
authors.forename: Shigeki
authors.initials: S
authors.lastname: Matsunaga
authors.forename: Masakatsu
authors.initials: M
authors.lastname: Shibasaki
mesh_terms: D002384:Catalysis; D004852:Epoxy Compounds / Q000138:chemical synthesis*; D007659:Ketones / Q000737:chemistry*; D009943:Organophosphorus Compounds; D013452:Sulfonium Compounds / Q000737:chemistry*
chemical_list: D004852:Epoxy Compounds; D007659:Ketones; D009943:Organophosphorus Compounds; D013452:Sulfonium Compounds; C525609:dimethyloxosulfonium methylide