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Published on: March 19, 2020
Tetra-kis(μ-4-methyl-benzoato-κO:O')bis-[(isonicotinamide-κN)copper(II)]
Abstract:
In the title centrosymmetric binuclear complex, [Cu(2)(C(8)H(7)O(2))(4)(C(6)H(6)N(2)O)(2)], the Cu atoms [Cu⋯Cu = 2.6375 (6) Å] are bridged by four 4-methyl-benzoate (PMB) ligands. The four nearest O atoms around each Cu(II) ion form a distorted square-planar arrangement, and the distorted square-pyramidal coordination is completed by the pyridine N atom of the isonicotinamide (INA) ligand. Each Cu(II) ion is displaced by 0.2633 (1) Å from the plane of the four O atoms, with an average Cu-O distance of 1.974 (2) Å. The dihedral angles between carboxyl-ate groups and the adjacent benzene rings are 7.88 (19) and 9.68 (10)°, while the benzene rings are oriented at a dihedral angle of 85.90 (9)°. The pyridine ring is oriented at dihedral angles of 8.59 (7) and 83.89 (9)° with respect to the benzene rings. In the crystal structure, inter-molecular N-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional network. π-π contacts between the benzene rings and between the pyridine and benzene rings, [centroid-centroid distances = 3.563 (2) and 3.484 (2) Å, respectively] may further stabilize the crystal structure.
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