Tetra-kis[μ-4-(methyl-amino)-benzoato-κO:O']bis-[(N,N-diethyl-nicotinamide-N)zinc(II)] dihydrate

Acta Crystallogr Sect E Struct Rep Online. 2009 Oct 10;65(Pt 11):m1328-9. doi: 10.1107/S1600536809040409.

Abstract

The title mol-ecule, [Zn(2)(C(8)H(8)NO(2))(4)(C(10)H(14)N(2)O)(2)]·2H(2)O, is a centrosymmetric binuclear complex, with two Zn(II) ions [Zn⋯Zn' = 2.9301 (4) Å] bridged by four methyl-amino-benzoate (MAB) ligands. The four nearest O atoms around each Zn(II) ion form a distorted square-planar arrangement with the distorted square-pyramidal coordination completed by the pyridine N atom of the N,N-diethyl-nicotinamide (DENA) ligand. Each Zn(II) ion is displaced by 0.3519 (2) Å from the plane of the four O atoms, with an average Zn-O distance of 2.030 Å. The dihedral angles between carboxyl-ate groups and adjacent benzene rings are 10.57 (10) and 16.63 (12)°, while the benzene rings are oriented at a dihedral angle of 81.84 (5)°. The pyridine ring is oriented at dihedral angles of 40.49 (6) and 51.25 (6)° with respect to the benzene rings. 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 inversion-related pyridine rings [centroid-centroid distance = 3.633 (1) Å] may further stabilize the crystal structure.