Synthesis and characterization of novel four heterodimetallic mixed metal complexes of 2,6-pyridinedicarboxylic acid

Abstract

Four novel hetero dimetallic mixed metal complexes of 2,6-pyridinedicarboxylic acid       (H₂dipic), [Ni(H₂O)₅Co(dipic)₂] (1), [Co(H₂O)₅Co(dipic)₂][Ni(H₂O)₅Ni(dipic)₂][Co(dipic)(H₂O)₃] (2), [Cu(H₂O)₅Ni(dipic)₂]₂[Co(dipic)(H₂O)] (3) and [Ni(H₂O)₅Cu(dipic)₂]₂[Co(dipic)(H₂O)] (4) have been prepared and characterized by elemental, AAS, spectral (IR and UV-Vis), and thermal analyses, as well as by using magnetic measurement and molar conductivity techniques. The results indicate that metal ions coordinate with 2,6-pyridinedicarboxylate ions (dipic^2-) nitrogen atoms and carboxylate oxygen atoms of ligands. The mole ratio of dipic^2- and metal ions in the complexes have been determined to be 2:2 (Co, Ni) for 1, 5:5 (3Co, 2Ni) for 2, 5:5 (Co, 2Ni and 2Cu) for 3 and 5:5 (Co, 2Ni and 2Cu) for 4 according to the results of elemental analysis. The structures of 1-4 might be proposed as octahedral ([Cu(dipic)(H₂O)] unit for 2 square plane) according to results of spectroscopic analysis. The TG and DTA properties of compounds have been studied.

KEY WORDS: 2,6-Pyridinedicarboxylic acid, Mixed metal, Metal complex

Bull. Chem. Soc. Ethiop. 2020, 34(2), 313-321

DOI: https://dx.doi.org/10.4314/bcse.v34i2.9