title: Aromatic Methoxylation and Hydroxylation by Organometallic High-Valent Nickel Complexes.
abstract: Herein we report the synthesis and reactivity of several organometallic Ni(III) complexes stabilized by a modified tetradentate pyridinophane ligand containing one phenyl group. A room temperature stable dicationic Ni(III)-disolvento complex was also isolated, and the presence of two available cis coordination sites in this complex offers an opportunity to probe the C-heteroatom bond formation reactivity of high-valent Ni centers. Interestingly, the Ni(III)-dihydroxide and Ni(III)-dimethoxide species can be synthesized, and they undergo aryl methoxylation and hydroxylation that is favored by addition of oxidant, which also limits the β-hydride elimination side reaction. Overall, these results provide strong evidence for the involvement of high-valent organometallic Ni species, possibly both Ni(III) and Ni(IV) species, in oxidatively induced C-heteroatom bond formation reactions.
authors.affiliation: †Department of Chemistry, Washington University, One Brookings Drive, St. Louis, Missouri 63130-4899, United States.
authors.forename: Wen
authors.initials: W
authors.lastname: Zhou
authors.affiliation: †Department of Chemistry, Washington University, One Brookings Drive, St. Louis, Missouri 63130-4899, United States.
authors.forename: Jason W
authors.initials: JW
authors.lastname: Schultz
authors.affiliation: ‡Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri 63121-4400, United States.
authors.forename: Nigam P
authors.initials: NP
authors.lastname: Rath
authors.affiliation: †Department of Chemistry, Washington University, One Brookings Drive, St. Louis, Missouri 63130-4899, United States.
authors.forename: Liviu M
authors.initials: LM
authors.lastname: Mirica
mesh_terms: D001372:Aza Compounds / Q000138:chemical synthesis / Q000737:chemistry; D001952:Bridged-Ring Compounds / Q000138:chemical synthesis / Q000737:chemistry; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry*; D006841:Hydrocarbons, Aromatic / Q000138:chemical synthesis / Q000737:chemistry*; D006900:Hydroxylation; D008024:Ligands; D008958:Models, Molecular; D009532:Nickel / Q000737:chemistry*; D010084:Oxidation-Reduction
chemical_list: D001372:Aza Compounds; D001952:Bridged-Ring Compounds; D056831:Coordination Complexes; D006841:Hydrocarbons, Aromatic; D008024:Ligands; C068781:2,6-pyridinophane; D009532:Nickel