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Access to Formally Ni(I) States in a Heterobimetallic NiZn System.

ABSTRACT: Heterobimetallic NiZn complexes featuring metal centers in distinct coordination environments have been synthesized using diimine-dioxime ligands as binucleating scaffolds. A tetramethylfuran-containing ligand derivative enables a stable one-electron-reduced S = 1/2 species to be accessed using Cp2Co as a chemical reductant. The resulting pseudo-square planar complex exhibits spectroscopic and crystallographic characteristics of a ligand-centered radical bound to a Ni(II) center. Upon coordination of a ?-acidic ligand such as PPh3, however, a five-coordinate Ni(I) metalloradical is formed. The electronic structures of these reduced species provide insight into the subtle effects of ligand structure on the potential and reversibility of the NiII/I couple for complexes of redox-active tetraazamacrocycles.

SUBMITTER: Uyeda C

PROVIDER: S-EPMC4300139 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Access to Formally Ni(I) States in a Heterobimetallic NiZn System.

Uyeda Christopher C Peters Jonas C JC

Chemical science 20130101 1

Heterobimetallic NiZn complexes featuring metal centers in distinct coordination environments have been synthesized using diimine-dioxime ligands as binucleating scaffolds. A tetramethylfuran-containing ligand derivative enables a stable one-electron-reduced <i>S</i> = 1/2 species to be accessed using Cp<sub>2</sub>Co as a chemical reductant. The resulting pseudo-square planar complex exhibits spectroscopic and crystallographic characteristics of a ligand-centered radical bound to a Ni(II) cente ...[more]

PMID: 25614786

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