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Alkaline earth metal-assisted dinitrogen activation at nickel.

ABSTRACT: Rare examples of trinuclear [Ni-N₂-M-N₂-Ni] core (M = Ca, Mg) with linear bridged dinitrogen ligands are reported in this work. The reduction of [ⁱPr₂NN]Ni(μ-Br)₂Li(thf)₂ (1) (ⁱPr₂NN = 2,4-bis-(2,6-diisopropylphenylimido)pentyl) with elemental Mg or Ca in THF under an atmosphere of dinitrogen yields the complex {ⁱPr₂NNNi(μ-N₂)}₂M (thf)₄ (M = Mg, complex 2 and M = Ca, complex 3). The bridging end-on (μ-N₂)₂M(thf)₄ moiety connects the two [ⁱPr₂NNNi]^- nickelate fragments. A combination of X-ray crystallography, solution and solid-state spectroscopy have been applied to characterize complexes 2 and 3, and DFT studies have been used to help explain the bonding and electronic structure in these unique Ni-N₂-Mg and Ni-N₂-Ca complexes.

SUBMITTER: Knoell T

PROVIDER: S-EPMC10922974 | biostudies-literature | 2024 Mar

REPOSITORIES: biostudies-literature

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Alkaline earth metal-assisted dinitrogen activation at nickel.

Knoell Theresa T Polanco Jocelyn J MacMillan Samantha N SN Bertke Jeffery A JA Foroutan-Nejad Cina C Lancaster Kyle M KM 'Gus' Bakhoda Abolghasem A

Dalton transactions (Cambridge, England : 2003) 20240305 10

Rare examples of trinuclear [Ni-N2-M-N2-Ni] core (M = Ca, Mg) with linear bridged dinitrogen ligands are reported in this work. The reduction of [iPr2NN]Ni(μ-Br)2Li(thf)2 (1) (iPr2NN = 2,4-bis-(2,6-diisopropylphenylimido)pentyl) with elemental Mg or Ca in THF under an atmosphere of dinitrogen yields the complex {iPr2NNNi(μ-N2)}2M (thf)4 (M = Mg, complex 2 ...[more]

PMID: 38362644

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