title: Marked deuterium isotope effects on the enantioselectivity in rhodium-catalyzed asymmetric hydrogenation of enamides.
abstract: Deuterium isotope effects on the enantioselectivity in the rhodium-catalyzed asymmetric hydrogenation of enamides and related substrates have been studied. Distinct deuterium isotope effects were observed in the hydrogenation of aryl-substituted enamides having an ortho substituent that is capable of forming a hydrogen bond. The observed isotope effects are interpreted in terms of the competitive reactions of two dihydride intermediates and dideuteride intermediates that exist in equilibrium in the catalytic cycle.
authors.affiliation: Graduate School of Science, Chiba University, Yayoi-cho, Inage-ku, Chiba 263-8522, Japan. imamoto@faculty.chiba-u.jp
authors.forename: Tsuneo
authors.initials: T
authors.lastname: Imamoto
authors.forename: Takuma
authors.initials: T
authors.lastname: Itoh
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Yoshida
authors.forename: Ilya D
authors.initials: ID
authors.lastname: Gridnev