title: Oxovanadium complex-catalyzed aerobic oxidation of propargylic alcohols.
abstract: A catalytic system consisting of vanadium oxyacetylacetonate [VO(acac)(2)] and 3 A molecular sieves (MS3A) in acetonitrile works effectively for the aerobic oxidation of propargylic alcohols [R(1)CH(OH)Ctbd1;CR(2)] to the corresponding carbonyl compounds under an atmospheric pressure of molecular oxygen. Although the reactivity of alpha-acetylenic alkanols (R(1) = alkyl) is lower compared to that of the alcohols of R(1) = aryl, alkenyl, and alkynyl, the use of VO(hfac)(2) as a catalyst and the addition of hexafluoroacetylacetone improve the product yield in these cases. A catalytic cycle involving a vanadium(V) alcoholate species and beta-hydrogen elimination from it has been proposed for this oxidation.
authors.affiliation: Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
authors.forename: Yasunari
authors.initials: Y
authors.lastname: Maeda
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Kakiuchi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Matsumura
authors.forename: Takahiro
authors.initials: T
authors.lastname: Nishimura
authors.forename: Takashi
authors.initials: T
authors.lastname: Kawamura
authors.forename: Sakae
authors.initials: S
authors.lastname: Uemura