Electrochemical Synthesis and Characterization of Copper(II) and Zinc(II) Coordination Compounds with Nicotinic and Picolinic Acids

New methods for the electrochemical synthesis of copper(II) and zinc(II) coordination compounds with pyridinecarboxylic acids (nicotinic and picolinic) have been developed. The resulting compounds were characterized by quantitative analysis and IR spectroscopy. The vibrational frequencies of the synthesized compounds were calculated by a DFT quantum-chemical method, and the experimental IR spectra were interpreted on this basis. It was found that pyridinecarboxylate ions in all cases are coordinated both at the nitrogen atom and at the carboxylate group, however, in the case of nicotinic acid, this leads to the formation of coordination polymers, whereas for picolinic acid, the formation of mononuclear complexes is typical.