Pyridine-2,5-dicarboxylic acid complexes of nickel(II) with 2,2′-bipyridine and 1,10-phenanthroline coligands; syntheses, crystal structures, spectroscopic and thermal studies

Abstract

Two pyridine-2,5-dicarboxylic acid (pydcH 2 ) complexes of nickel(II) with 2,2 0 -bipyridine and 1,10-phenanthroline were synthesized and characterized by elemental, spectroscopic, thermal analysis, magnetic measurements and single crystal X-ray diffraction techniques. Both [Ni(pydc)(bipy) 2 ]Á7H 2 O and [Ni(pydc)(phen) 2 ]Á6.5H 2 O crystallize in the monoclinic system and P2 1 /c space group. The Ni(II) ions are coordinated by two bidentate bipy or phen ligands and one pydc dianion in a distorted octahedral geometry. The pydc ligand is coordinated through the pyridine nitrogen atom and oxygen atom of carboxyl group as a bidentate ligand. Both carboxylate groups of pydc are deprotonated but only the 2-carboxylate is coordinated to the metal. Thermal decompositions of the complexes have been studied over the range 30-600°C on heating in a static air atmosphere.

Hexaaquanickel(II) tetraaquabis(μ-pyridine-2,6-dicarboxylato)bis(pyridine-2,6-dicarboxylato)trinickelate(II) octahydrate

“…For metal complexes formed by pyridinedicarboxylic acids, see: Aghabozorg et al (2008);Ç olak et al (2008); Moghimi et al (2005).…”

Structure of Diaqua 1,10-Phenanthroline Cobalt (II) 2,5-Pyridinedicarboxylate Monohydrate

“…PDC)(PHEN)(H 2 O)ÁH 2 O] [13] the first lanthanide PDC compound with PHEN and water; [Zn(PHEN)(PDC)Á0.5H 2 O] [14], in which the structure was co-built with PDC, PHEN and small amount of guest water; [Zn(PHEN)(PDC) H 2 O] and [Cd(PHEN) (PDC)] [15] where the two structures were quite similar with the distinction of one more guest water molecule in the Zn compound; [Mn(PHEN)(PDC)(H 2 O) 2 ÁH 2 O] [16], which showed the comprehensive hydrogen bonding interaction resulted from the coordinate and guest water molecules; while the last one [Ni(PDC)(PHEN) 2 Á6.5H 2 O][17], of which featured the first example of Ni 2? coordinating to two PHEN species in one molecule.During the synthesis of the complexes of PDC with mixed 3d-4f metal atoms, we obtained the title compound 1.…”