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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.

SUBMITTER: Zhang K

PROVIDER: S-EPMC3092490 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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N-Heterocyclic Carbene Bound Nickel(I) Complexes and Their Roles in Catalysis.

Zhang Kainan K Conda-Sheridan Martin M Cooke Shayna S Louie Janis J

Organometallics 20110501 9

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) catalys ...[more]

PMID: 21572533

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