Synthesis and characterization of ten new 1D, 2D and 3D-coordination polymers with oxygen or nitrogen containing ligands by using different metal cations

Abstract

The present work deals with the preparation and characterization of ten new coordination polymers prepared from different metal ions and ligands by different synthetic methods. In addition to the structural characterization of these compounds by means of X-ray singlecrystal diffraction data, the focus is on the consideration of thermal and spectroscopic properties. The new silver coordination polymer exhibits very unique, robust and interesting polymeric structure with high thermal stability. Two new lanthanide coordination polymers (neodymium and samarium) have been synthesized with H2FDA = 2,5-furandicarboxylic acid in DMF as solvent via capped tube method. The compounds are iso-structural and exhibit threedimensional coordination polymers. The goal of using DMF as pure solvent instead of mixture of water and other solvents was to synthesize new coordination polymer which might show very intensive luminescence effect. The investigation has turned out that these compounds emerge no significant luminescence effect. As it has been reported in previous works in which the H2FDA = 2,5-furandicarboxylic acid was used for construction of lanthanide coordination polymers in water as solvent, however the compounds have exposed very interesting luminescence properties [229230]. A new cerium coordination polymer has been produced with ligand (H2pdc = 3,5-pyrazoledicarboxylic acid) under solvothermal condition in DMF as solvent. Indeed, ligand (H2pdc = 3,5-pyrazoledicarboxylic acid) is very versatile to construct coordination network by various coordination modes. Three copper (I) coordination polymers have been successfully synthesized via solvent diffusion technique in test tube. The compounds all display 1D polymeric structure with rather similar coordination environment around metal ions. Moreover, they are very stable against temperature rising. The compounds [Pb3(CH3COO)2(N3)4]n and [Na2Pb2(CH3COO)6]n were synthesized under same synthesis conditions and starting materials but with different metal salt and ligand ratios. Interestingly, the both products show three-dimentional frameworks, however they expose different coordination structures. Actually, the investigation shows that the changing metal salt and ligand ratio can result in the formation different structures of coordination networks, although they have been produced under same reaction conditions. Compound [Pb(DHBDA)]n has been made with ligand 2,5-Dihydroxy-1,4-benzenediacetic acid which has been reported in very few works for constructing coordination compounds.