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]·2H2O (1), (Hmapy)2[Zn(pydc)2(H2O)2]·2H2O (2), [Zn(pydc)(ampy)(H2O)]·H2O (3) and [Zn(pydc)(H2O)(hmpy)] (4) compounds (H2pydc = 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 π⋯π, CO⋯π and C–H⋯π interactions play an important role in the construction of a three-dimensional supramolecular framework.

The [Zn(pydc)(H2O)4]·2H2O (1), (Hmapy)2[Zn(pydc)2(H2O)2]·2H2O (2), [Zn(pydc)(ampy)(H2O)]·H2O (3) and [Zn(pydc)(H2O)(hmpy)] (4) compounds (H2pydc = 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.Figure optionsDownload as PowerPoint slide