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Updated: May 22, 2026
06:31
Preparation of SNS Cobalt(II) Pincer Model Complexes of Liver Alcohol Dehydrogenase
Published on: March 19, 2020
Poly[di-μ(9)-citrato-cobalt(II)tetra-sodium]
Zhen Liu1, Ruijing Tian, Rui Mao
1Department of Materials and Chemical Engineering, Ministry of Education Key Laboratory of Advanced Materials of Tropical Island Resources, Hainan University, Haikou 570228, Hainan Province, People's Republic of China.
Summary
This study details the hydrothermal synthesis of a novel cobalt-sodium citrate framework. The structure reveals interconnected building units forming a 3D network, highlighting citrate coordination chemistry.
Area of Science:
- Inorganic Chemistry
- Crystal Engineering
- Materials Science
Background:
- Metal-organic frameworks (MOFs) offer tunable properties for various applications.
- Citrate, a versatile ligand, can coordinate with multiple metal ions.
- Understanding the self-assembly of coordination polymers is crucial for designing new materials.
Purpose of the Study:
- To synthesize and characterize a novel cobalt-sodium citrate coordination compound.
- To elucidate the crystal structure and coordination environment of the metal ions.
- To investigate the role of citrate in forming a three-dimensional framework.
Main Methods:
- Hydrothermal synthesis technique.
- Single-crystal X-ray diffraction for structural determination.
- Analysis of coordination modes and hydrogen bonding interactions.
Main Results:
- The title compound, [CoNa(4)(C(6)H(5)O(7))(2)](n), was synthesized as a minor product.
- The cobalt(II) cation is coordinated by six oxygen atoms from two citrate units.
- Two distinct sodium ions exhibit varying coordination numbers (5 and 6) with citrate oxygen atoms.
- Citrate carboxylate groups are fully deprotonated, while the hydroxyl group participates in hydrogen bonding.
- A 3D framework is formed through the coordination of citrate groups to sodium ions, linking cobalt-citrate units.
Conclusions:
- The study successfully characterized a novel 3D cobalt-sodium citrate coordination framework.
- The diverse coordination modes of citrate ligands play a key role in framework assembly.
- This work contributes to the understanding of coordination chemistry in mixed-metal citrate systems.
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