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Updated: Jun 1, 2026
06:31
Preparation of SNS Cobalt(II) Pincer Model Complexes of Liver Alcohol Dehydrogenase
Published on: March 19, 2020
Poly[bis-(cyanato-κN)bis-(μ-pyrazine-κN:N')cobalt(II)]
Mario Wriedt1, Inke Jess, Christian Näther
1Institut für Anorganische Chemie, Christian-Albrechts-Universität Kiel, Max-Eyth-Strasse 2, D-24118 Kiel, Germany.
Summary
The crystal structure reveals cobalt(II) coordinated with pyrazine and cyanate, forming layered chains. These chains exhibit disorder in cyanate anion orientations, impacting the overall crystal packing.
Area of Science:
- Coordination Chemistry
- Crystal Engineering
- Materials Science
Background:
- Understanding the coordination behavior of transition metals like cobalt(II) is crucial for designing novel materials.
- Pyrazine and cyanate are versatile ligands capable of forming extended network structures.
- Crystal structure determination provides fundamental insights into chemical bonding and supramolecular assembly.
Purpose of the Study:
- To elucidate the crystal structure of a novel cobalt(II) coordination compound with pyrazine and cyanate ligands.
- To investigate the coordination geometry around the cobalt(II) center.
- To characterize the supramolecular architecture and dimensionality of the resulting network.
Main Methods:
- Single-crystal X-ray diffraction analysis was employed to determine the three-dimensional crystal structure.
- The crystal structure was refined using a split model to account for disordered atoms.
- Coordination geometry and network topology were analyzed based on crystallographic data.
Main Results:
- The cobalt(II) cation adopts a distorted octahedral coordination geometry, bonded to four N-donating pyrazine ligands and two N-donating cyanate anions.
- The crystal structure features one-dimensional coordination chains bridged by pyrazine ligands, which further assemble into two-dimensional layers.
- Significant positional disorder was observed for the carbon and oxygen atoms of the cyanate anions, requiring a split-site refinement model.
Conclusions:
- The study successfully determined the crystal structure of the [Co(NCO)2(C4H4N2)2]n compound, revealing a layered coordination network.
- The observed disorder in cyanate anions highlights the flexibility and potential complexity in such coordination polymers.
- This work contributes to the understanding of metal-organic framework construction with mixed ligands.
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