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Published on: March 19, 2020
Diaqua-bis(4-methyl-benzoato-κO)bis-(nicotinamide-κN)nickel(II)
Abstract:
The title Ni(II) complex, [Ni(C(8)H(7)O(2))(2)(C(6)H(6)N(2)O)(2)(H(2)O)(2)], is centrosymmetric with the Ni atom located on an inversion center. The mol-ecule contains two 4-methyl-benzoate (PMB) and two nicotinamide (NA) ligands and two coordinated water mol-ecules, all ligands being monodentate. The four O atoms in the equatorial plane around the Ni atom 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 26.15 (10)°, while the pyridine and benzene rings are oriented at a dihedral angle of 87.81 (4)°. In the crystal structure, inter-molecular O-H⋯O and N-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional network. The π-π contact between the benzene rings [centroid-centroid distance = 3.896 (1) Å] may further stabilize the crystal structure. A weak C-H⋯π inter-action involving the pyridine ring also occurs.
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