title: Nickel(0)/N-Heterocyclic Carbene-Catalyzed Asymmetric [2 + 2 + 2] Cycloaddition of Two Enones and an Alkyne: Access to Cyclohexenes with Four Contiguous Stereogenic Centers.
abstract: A nickel(0)/chiral N-heterocyclic carbene (NHC)-catalyzed fully intermolecular, enantioselective [2 + 2 + 2] cycloaddition of two enones and an alkyne has been developed to access enantioenriched cyclohexenes. A single diastereomer was obtained with a successive generation of four contiguous stereogenic centers. The absolute configuration of cyclohexene derivative 3aa was determined by X-ray diffraction and circular dichroism (CD) spectral studies.
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, Osaka University , Suita, Osaka 565-0871, Japan.
authors.forename: Ravindra
authors.initials: R
authors.lastname: Kumar
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, Osaka University , Suita, Osaka 565-0871, Japan.
authors.forename: Hiromu
authors.initials: H
authors.lastname: Tokura
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, Osaka University , Suita, Osaka 565-0871, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Nishimura
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, Osaka University , Suita, Osaka 565-0871, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Mori
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, Osaka University , Suita, Osaka 565-0871, Japan.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Hoshimoto
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, Osaka University , Suita, Osaka 565-0871, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Ohashi
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, Osaka University , Suita, Osaka 565-0871, Japan.
authors.forename: Sensuke
authors.initials: S
authors.lastname: Ogoshi