Copper ferrite (CuFe2O4) samples were prepared by the co-precipitation method without and in the presence of a polymer stabilizer (polyvinyl alcohol, PVA) followed by heat treatment at 500, 700, and 900°C and electrochemical reduction. The structure and morphological features of the samples were investigated by X-ray phase analysis and electron microscopy. It was established that copper (II) ferrite is reduced in an electrochemical system with the formation of Fe-Cu composites with different content of reduced metals, which is influenced by the heat treatment temperature. Copper ferrite prepared with the use of the polymer stabilizer is partially reduced during thermolysis, additionally in an electrochemical cell. The Fe-Cu composites were employed as electrocatalysts in the electrohydrogenation of p-nitrobenzoic acid and exhibited good activity in this process. To study the interaction in the CuFe2O4 + PVA complexes, the quantum-chemical calculations were performed using the density functional theory methods for the simplified metal-containing systems (atoms and ions of copper (II), iron (III), Cu2, Fe2 molecules) as well as dimers and trimers modeling the structure of polyvinyl alcohol.

Structural and spectroscopic properties of quinolizidine alkaloids lupinine and epilupinine stereoisomers were studied theoretically. The influence of the calculation method and structural change in the molecule on the results of geometry and other properties of compounds was considered. The equilibrium geometry, harmonic vibrational frequencies and infrared intensities were obtained by means of density functional theory (DFT/B3LYP) calculations with the splitvalence medium-sized 6-31G(d) basis and Dunning’s correlation consistent basis set cc-pVDZ. From the optimized structure of the (+)-lupinine and (+)-epilupinine molecules, geometric parameters were compared with the literature X-ray experimental data. Structural and vibrational parameters for the (-)-lupinine and (-)-epilupinine molecules are predicted by theoretical calculations at B3LYP/6-31G(d) and B3LYP/cc-pVDZ levels of theory. Some physical characteristics for the title compounds, such as total electronic energy, zero-point energy, rotational constants and dipole moments were also defined by DFT methods. The thermodynamic functions of the title compounds were performed at the same theory levels. Stationary points are identified by the solution of the oscillatory problem.

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There has been presented data on the synthesis of monoamides and cyclic imides which are derivatives of isonicotinic acid hydrazide. Cyclic anhydrides of carboxylic acids (succinic, maleic and phthalic) easily react with the hydrazide of isonicotinic acid with cycle opening, forming isonicotinoylhydrazide of dicarboxylic acids, and under more severe conditions the latter are transformed into cyclic acid imides. The structures of the synthesized compounds were studied using 1H- and 13C-NMR spectroscopy, as well as data from twodimensional COSY (1H-1H) and HMQC (1H-13C) spectra. The values of chemical shifts, multiplicity and integral intensity of 1H and 13C signals in one-dimensional NMR spectra were determined. Homo- and heteronuclear interactions confirming the structure of the studied compounds were established using spectra in the COSY (1H-1H) and HMQC (1H-13C) formats. In the approximation of the density functional B3LYP with a base set of 6-31G(d), the enthalpy of the reactions ΔHr in the absence and in the presence of a solvent — isopropanol (self-consistent reaction field method) were calculated quantum-chemically.

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