title: An in Situ Approach to Nickel-Catalyzed Cycloaddition of Alkynes and 3-Azetidinones.
abstract: An efficient and convenient procedure that generates the active Ni(0) catalyst in situ from cheap, air stable Ni(II) precursors is developed for the [4 + 2]-cycloaddition of alkynes and 3-azetidinones. The reaction affords useful 3-dehydropiperidinones in comparable yields to the reported Ni(0) procedure. Additionally, the cycloaddition with 3-oxetanone afforded the 3-dehydropyranone product. Chiral 2-substituted azetidinones were also tolerated to form substituted dehydropiperidinones in high yield and enantiomeric excess.
authors.affiliation: Department of Chemistry, University of Utah , 315 South, 1400 East, Salt Lake City, Utah 84112-0850, United States.
authors.forename: Ashish
authors.initials: A
authors.lastname: Thakur
authors.affiliation: Department of Chemistry, University of Utah , 315 South, 1400 East, Salt Lake City, Utah 84112-0850, United States.
authors.forename: Judah L
authors.initials: JL
authors.lastname: Evangelista
authors.affiliation: Department of Chemistry, University of Utah , 315 South, 1400 East, Salt Lake City, Utah 84112-0850, United States.
authors.forename: Puneet
authors.initials: P
authors.lastname: Kumar
authors.affiliation: Department of Chemistry, University of Utah , 315 South, 1400 East, Salt Lake City, Utah 84112-0850, United States.
authors.forename: Janis
authors.initials: J
authors.lastname: Louie
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D001384:Azetidines / Q000737:chemistry*; D002384:Catalysis; D003500:Cyclization; D015394:Molecular Structure; D009532:Nickel / Q000737:chemistry*; D010881:Piperidones / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D000480:Alkynes; D001384:Azetidines; D010881:Piperidones; D009532:Nickel