title: N-Heterocyclic Carbene Bound Nickel(I) Complexes and Their Roles in Catalysis.
abstract: New paramagnetic Ni(I)(IMes)(2)X (IMes: 1,3-bis-(2,4,6-trimethylphenyl)-imidazol-2-ylidene) were prepared from the reaction of Ni(IMes)(2) with aryl halides. Products that would arise from oxidative addition were not observed. In contrast, Ni(II)(tmiy)(2)(X)(Ar) was formed from the oxidative addition of aryl halides to Ni bound by a sterically-less hindered NHC ligand, tmiy (tetramethylimidazol-2-ylidene). The paramagnetic Ni(I)(IMes)(2)X complexes were compared to known Ni(0) and Ni(II) catalysts for Kumada and Suzuki coupling reactions. Stoichiometric reactions between the Ni(I)(IMes)(2)X complexes with aryl halides and transmetallating agents were also evaluated.
authors.affiliation: Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850.
authors.forename: Kainan
authors.initials: K
authors.lastname: Zhang
authors.forename: Martin
authors.initials: M
authors.lastname: Conda-Sheridan
authors.forename: Shayna
authors.initials: S
authors.lastname: Cooke
authors.forename: Janis
authors.initials: J
authors.lastname: Louie