Synthesis, structural characterisation of zinc(II)-pyridine-2,5-dicarboxylate complexes and self-assembled 1D water cluster in a supramolecular architecture

The (Zn(pydc)(H2O)(4)]center dot 2H(2)O (1), (Hmapy)(2)[Zn(pydc)(2)(H2O)(2)]center dot 2H(2)O (2), [Zn(pydc)(ampy)(H2O)]center dot H2O (3) and [Zn(pydc)(H2O)(hmpy)] (4) compounds (H(2)pydc = pyridine-2,5-dicarboxylic acid or isocinchomeronic acid, mapy = 2-amino-6-methylpyridine ampy = 2-aminomethylpyridine and hmpy = 2-hydroxymethylpyridine) were synthesised and characterised by elemental analysis, magnetic and spectroscopic measurements (UV-Vis and IR spectra) and single crystal X-ray diffraction technique. The complexes 1 and 2 have distorted octahedral geometries, while the complexes 3 and 4 have distorted square pyramidal geometry. The pydc coordinated to the Zn(II) ions through nitrogen atom of pyrimidine ring and oxygen atom of carboxylate group as a bidentate ligand. In the complexes, the strong hydrogen bonds between water molecules and carboxylate groups and relatively weak pi center dot center dot center dot pi, C=O center dot center dot center dot pi and C-H center dot center dot center dot pi interactions play an important role in the construction of a three-dimensional supramolecular framework. (C) 2010 Elsevier Ltd. All rights reserved.