ABSTRACT
Zinc(II) carboxylates with O-, S- and N-donor ligands are interesting for their structural features, as well as for their antibacterial and antifungal activities. The one-dimensional zinc(II) coordination complex catena-poly[[bis(2,4-dichlorobenzoato-κO)zinc(II)]-µ-isonicotinamide-κ(2)N(1):O], [Zn(C7H3Cl2O2)2(C6H6N2O)]n, has been prepared and characterized by IR spectroscopy, single-crystal X-ray analysis and thermal analysis. The tetrahedral ZnO3N coordination about the Zn(II) cation is built up by the N atom of the pyridine ring, an O atom of the carbonyl group of the isonicotinamide ligand and two O atoms of two dichlorobenzoate ligands. Isonicotinamide serves as a bridge between tetrahedra, with a Zn···Zn distance of 8.8161â (7)â Å. Additionally, π-π interactions between the planar benzene rings contribute to the stabilization of the extended structure. The structure is also stabilized by intermolecular hydrogen bonds between the amino and carboxylate groups of the ligands, forming a two-dimensional network. During thermal decomposition of the complex, isonicotinamide, dichlorobenzene and carbon dioxide were evolved. The final solid product of the thermal decomposition heated up to 1173â K was metallic zinc.
Subject(s)
Coordination Complexes/chemistry , Zinc/chemistry , Crystallography, X-Ray , Hydrogen Bonding , Ligands , Molecular Structure , Thermal ConductivityABSTRACT
The title mononuclear complex mol-ecule, [Zn(C(7)H(4)BrO(3))(2)(C(7)H(8)N(2)O)(2)(H(2)O)(2)], has a crystallographically imposed centre of symmetry. The zinc(II) atom is coordinated by two N atoms from two N-methyl-nicotinamide ligands, two O atoms from two 5-bromo-salicylate anions and two aqua O atoms in a slightly distorted octa-hedral geometry. Intra-molecular O-Hâ¯O hydrogen-bonding inter-actions are present. In the crystal structure, mol-ecules are linked by inter-molecular O-Hâ¯O and N-Hâ¯O hydrogen bonds, forming a two-dimensional network perpendicular to [100].
