COPPER COORDINATION COMPOUNDS BASED ON PYRIDYL-1,2,4-TRIAZOLES: STRUCTURE, CHARACTERIZATION AND APPLICATIONS
Authors:   Taras Shevchenko National University of Kyiv, Ukraine, Raspertova Ilona , Lampeka Rostyslav ,   Taras Shevchenko National University of Kyiv, Ukraine
Published: November 2023

The functional properties of copper complexes strongly depend on the coordination environment of the central atom. There are many works devoted to the study of the properties of N,N-donor ligands. The substituted dipyridyls and phenanthrolines have become widely used. The disadvantage of these ligand systems is the difficulty of the synthesis of functionalized derivatives. Thus, they were replaced by pyridyl-azoles. A special place among them is occupied by pyridyl-1,2,4-triazoles. They have a number of advantages, in particular, the convenience of methods for the synthesis of 1,2,4-triazoles from available starting substances, the presence of four donor nitrogen atoms, existence in three tautomeric forms, the possibility of easy modification and regulation of the hydrophilic-lipophilic characteristics of these compounds. The importance of triazole ligands has grown especially noticeably in recent years due to the intensive development of molecular magnetism, bioinorganic modeling and crystal engineering. Polynuclear clusters based on triazolate ions occupy a significant place in bioinorganic chemistry as models for the active centers of metalloproteins. Polynuclear complexes of copper(II) with triazoles most often exhibit magnetic properties due to the direct dependence of intermolecular interactions on the geometry of the bridging unit [Cu−(N=N)2−Cu]. The phenomenon of magnetic-structural correlation for binuclear complexes of copper(II) with N-donor ligands is quite widespread and attracts attention due to the availability of compounds with predicted antiferromagnetic properties. Copper(II) coordination compounds are also widely used as catalysts in oxidation reactions. Among the large number of catalysts based on coordination compounds, only a small part helps to obtain products with high selectivity and high yield of reactions. At the same time, catalytic oxidation is a key technology for converting naturally available petroleum-based raw materials into more useful organic chemicals such as alcohols. The search for new complex compounds capable of selectively and effectively catalyzing the passage of reactions is an important task of modern coordination chemistry. Most of the reactions require high temperatures or pressure, an inert environment for their progress, which affects the cost of practical application in industry. For researchers all over the world, the biggest challenge is to carry out catalysis under moderate conditions with non-toxic reagents, which will give an impetus to making the process cheaper in industry. As of today a large number of mononuclear and polynuclear coordination compounds based on pyridyl-1,2,4-triazoles with interesting magnetic properties and a new topology have been synthesized and characterized. The purpose of this work is to analyze and systematize aspects of the coordination chemistry of pyridyl-1,2,4-triazole and the field of application of copper coordination compounds based on them.