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Updated: Jun 1, 2026

Preparation of SNS Cobalt(II) Pincer Model Complexes of Liver Alcohol Dehydrogenase
Published on: March 19, 2020
Diaqua-bis(N,N-diethyl-nicotinamide-κN)bis-(4-methyl-benzoato-κO)cobalt(II)
Abstract:
In the centrosymmetric mononuclear title complex, [Co(C(8)H(7)O(2))(2)(C(10)H(14)N(2)O)(2)(H(2)O)(2)], the Co(II) ion is located on an inversion center. The asymmetric unit contains one 4-methyl-benzoate (PMB) anion, one N,N-diethyl-nicotinamide (DENA) ligand and one coordinated water mol-ecule. The four O atoms in the equatorial plane around the Co(II) ion form a slightly distorted square-planar arrangement, while the slightly distorted octa-hedral coordination is completed by the two pyridine N atoms of the DENA ligands in the axial positions. The dihedral angle between the carboxyl-ate group and the attached benzene ring is 3.73 (14)°, while the pyridine and benzene rings are oriented at a dihedral angle of 77.28 (6)°. In the crystal structure, inter-molecular O-H⋯O and C-H⋯O hydrogen bonds link the mol-ecules into a two-dimensional network parallel to (001). The structure is further stabilized by π-π contacts between the pyridine rings [centroid-centroid distance = 3.544 (1) Å] and weak C-H⋯π inter-actions involving the benzene ring.
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