title: Intermolecular hydrophosphination of alkynes and related carbon[bond]carbon multiple bonds catalyzed by organoytterbiums.
abstract: Intermolecular hydrophosphination of alkynes with diphenylphosphine is catalyzed by a Yb[bond]imine complex, [Yb(eta(2)-Ph(2)CNPh)(hmpa)(3)], to give alkenylphosphines and phosphine oxides after oxidative workup in good yields under mild conditions. This reaction is also applicable to various carbon[bond]carbon multiple bonds such as conjugated diynes and dienes, allenes, and styrene derivatives. Regio- and stereoselectivity and the scope and limitation of the present reaction clearly differ from those of the corresponding radical reaction. Instead, the reaction takes place through insertion of alkynes to a Yb[bond]PPh(2) species, followed by protonation. In fact, the Yb[bond]phosphido complex, [Yb(PPh(2))(2)(hmpa)(3)], is obtained from the imine complex and phosphine, which exhibits similar catalyst activity for the hydrophosphination. The empirical rate law is nu = k[catalyst](2) [alkyne](1)[phosphine](0) at least under the standard conditions.
authors.affiliation: Department of Chemistry and Chemical Engineering, Graduate School of Engineering, Hiroshima University, Kagamiyama, Higashi-Hiroshima 739-8527, Japan. ktakaki@hiroshima-u.ac.jp
authors.forename: Ken
authors.initials: K
authors.lastname: Takaki
authors.forename: Go
authors.initials: G
authors.lastname: Koshoji
authors.forename: Kimihiro
authors.initials: K
authors.lastname: Komeyama
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Takeda
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Shishido
authors.forename: Akira
authors.initials: A
authors.lastname: Kitani
authors.forename: Katsuomi
authors.initials: K
authors.lastname: Takehira