title: Nickel-catalyzed [4 + 2] cycloaddition of enones with alkynes.
abstract: A nickel-catalyzed [4 + 2] cycloaddition reaction has been developed where enones react with alkynes to afford polysubstituted pyrans. A mechanistic rationale is proposed, implying oxa-nickela cycle formation by oxidative cyclization of nickel to enone, followed by alkyne insertion.
authors.affiliation: Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Koyama
authors.forename: Takuya
authors.initials: T
authors.lastname: Kurahashi
authors.forename: Seijiro
authors.initials: S
authors.lastname: Matsubara
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D002384:Catalysis; D008958:Models, Molecular; D015394:Molecular Structure; D009532:Nickel / Q000737:chemistry*; D011083:Polycyclic Compounds / Q000737:chemistry*
chemical_list: D000480:Alkynes; D011083:Polycyclic Compounds; D009532:Nickel