COPPER(II) COMPLEX OF THE PYRAZINE-MODULATED OLIGO-αAMINOPYRIDINE AS A COORDINATION POLYMERS' PROMISING BUILDING BLOCK

Through the pyrazine-modulated tetrapyridyltriamine ligand N2-(pyrazin-2-yl)-N6-(6-(pyrazin-2ylamino)pyridin-2-yl)pyridine-2,6-diamine (H3pzpz) (1), a new mononuclear copper(II) complex [Cu(H3pzpz)(NO3)]·NO3·3H2O (2) has been synthesized and structurally characterized. The copper(II) atom in complex 2 exhibits a distorted square pyramidal geometry with an Addison parameter value of 0.39 (σ = 0.39). In compound (2), H3pzpz (1) acts as a tetradentate N4-donor ligand and coordinates to the Cu(1) ion in an anti-anti-anti-anti conformation. The single crystal X-ray analysis revealed a distorted square pyramidal geometry of the complex (2), which is consistent with the parameters of EPR spectra, measured magnetic moment susceptibility, and electronic spectrum studies. Observed extensive intermolecular hydrogen bond interactions (classical and non-classical) play an important role in the formation of the 3D supramolecular network and crystal packing of this complex. The complex (2) has been identified as a promising building block for the construction of coordination polymers.