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Updated: May 19, 2026

Preparation of SNS Cobalt(II) Pincer Model Complexes of Liver Alcohol Dehydrogenase
Published on: March 19, 2020
Diaqua-bis-(4-formyl-benzoato-κO(1))bis-(nicotinamide-κN(1))cobalt(II)
Abstract:
In the title complex, [Co(C(8)H(5)O(3))(2)(C(6)H(6)N(2)O)(2)(H(2)O)(2)], the Co(II) cation is located on an inversion center and is coordinated by two 4-formyl-benzoate (FB) anions, two nicotinamide (NA) ligands and two water mol-ecules. The four O atoms in the equatorial plane around the Co(II) cation form a slightly distorted square-planar arrangement, while the slightly distorted octa-hedral coordination is completed by the two N atoms of the NA ligands in the axial positions. The dihedral angle between the carboxyl-ate group and the adjacent benzene ring is 23.91 (9)°, while the pyridine and benzene rings are oriented at a dihedral angle of 88.84 (4)°. The coordinating water mol-ecule links with the carboxyl-ate group via an intra-molecular O-H⋯O hydrogen bond. In the crystal, N-H⋯O, O-H⋯O and weak C-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional supra-molecular network. π-π stacking between the parallel benzene rings of adjacent mol-ecules [centroid-centroid distance = 3.8505 (8) Å] may further stabilize the structure. A weak C-H⋯π inter-action also occurs in the crystal.
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