title: Non-precious metals catalyze formal [4 + 2] cycloaddition reactions of 1,2-diazines and siloxyalkynes under ambient conditions.
abstract: Copper(I) and nickel(0) complexes catalyze the formal [4 + 2] cycloaddition reactions of 1,2-diazines and siloxyalkynes, a reaction hitherto best catalyzed by silver salts. These catalysts based on earth abundant metals are not only competent, but the copper catalyst, in particular, promotes cycloadditions of pyrido[2,3-d]pyridazine and pyrido[3,4-d]pyridazine, enabling a new synthesis of quinoline and isoquinoline derivatives, as well as the formal [2 + 2] cycloaddition reaction of cyclohexenone with a siloxyalkyne.
authors.affiliation: Department of Chemistry, The University of Chicago , 5735 South Ellis Avenue, Chicago, Illinois 60637, United States.
authors.forename: Chintan S
authors.initials: CS
authors.lastname: Sumaria
authors.forename: Yunus E
authors.initials: YE
authors.lastname: Türkmen
authors.forename: Viresh H
authors.initials: VH
authors.lastname: Rawal
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D061565:Cycloaddition Reaction; D003512:Cyclohexanones / Q000737:chemistry*; D007546:Isoquinolines / Q000138:chemical synthesis / Q000737:chemistry; D015394:Molecular Structure; D009532:Nickel / Q000737:chemistry*; D011724:Pyridazines / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D011804:Quinolines / Q000138:chemical synthesis / Q000737:chemistry; D017655:Silicon Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D012834:Silver / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000480:Alkynes; D003512:Cyclohexanones; D007546:Isoquinolines; D011724:Pyridazines; D011725:Pyridines; D011804:Quinolines; D017655:Silicon Compounds; D012834:Silver; C028215:2-cyclohexen-1-one; D003300:Copper; D009532:Nickel