title: Chiral phosphoric-acid-catalyzed transfer hydrogenation of ethyl ketimine derivatives by using benzothiazoline.
abstract: Chiral phosphoric acid catalyzed transfer hydrogenation of ketimines derived from propiophenone derivatives and reductive amination of alkyl ethyl ketone derivatives were extensively examined in the presence of two representative hydrogen donors. The excellent enantioselective transfer hydrogenation was achieved by use of benzothiazoline as a hydrogen donor. The theoretical studies elucidated that the unsymmetrical structure of benzothiazoline plays an important role in high enantioselective hydrogenation.
authors.affiliation: Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588 (Japan).
authors.forename: Kodai
authors.initials: K
authors.lastname: Saito
authors.forename: Kosaku
authors.initials: K
authors.lastname: Horiguchi
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Shibata
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yamanaka
authors.forename: Takahiko
authors.initials: T
authors.lastname: Akiyama
keywords: hydrogen donor; hydrogenation; organocatalysis; reductive amination; theoretical studies