Vol 88, No 4 (2018)

Structural parameters and vibrational frequencies of the clusters (T_d)–Nb₄O₁₀, (C_3v)-TaNb₃O₁₀, (D_2d)-Nb₄O₁₀^–, and (C_s)-TaNb₃O₁₀^– were calculated. According to the (U)DFT/SDD calculations with BLYP, B3LYP, and PBE0 functionals magnetization of the anion (D_2d)-Nb₄O₁₀^– is distributed equally among four niobium atoms. In the anion (C_s)-TaNb₃O₁₀^– unpaired electron presumably occupies niobium atoms. The distinction in contributions from Nb atoms in the magnetization of the tantalum-containing cluster grows with the exchange component of the DFT functional in the series of functionals BLYP < B3LYP < PBE0 < UHF.

The kinetics of thermal decomposition of didecanoyl diperoxyadipate in different organic solvents have been studied. The primary homolytic dissociation of the peroxide bond (O–O) is accompanied by secondary induced chain decomposition processes. The reaction medium affects both the rate of primary homolytic decomposition and secondary decomposition processes. Correlation equations have been proposed for the rate constants of the reactions under study and physicochemical parameters of the solvents.

The effect of glycine and monoethanolamine on the stability and reductive activity of thiourea dioxide in the reaction with acid orange II dye was studied. It was found that, in contrast to glycine, introduction of additives of monoethanolamine into aqueous solution of thiourea dioxide substantially increases its reductive activity in alkaline solutions, although the stability of the thiourea dioxide monoethanol amine derivative in alkaline solutions is much lower than that of thiourea dioxide and the product of its reaction with glycine.

N-(1- and 4-diamantyl)amides have been synthesized by the reaction of diamantane with organic nitriles in the presence of CBr₄ under the action of granulated zeolite FeHY. The optimal ratios of the catalyst, reagents and the conditions for preparation of 1-N-diamantylamides in high yield have been found.

An effective method for the synthesis of new acridine-9(10H)-one (acridone) derivatives containing 1,2,3-triazole fragment was developed. A number of new triazole-containing compounds were synthesized from propargyl acridone acetate and their antimicrobial activity was studied.

The reactions of 4-(2-bromophenyl)-1,2,3-thia-and -selenadiazoles with amines in the presence of potassium carbonate and copper(I) iodide afforded 2-aminobenzo[b]chalcogenophenes. The corresponding thiaand selenamides, prepared by interaction of 4-(2-bromophenyl)-1,2,3-thia- and -selenadiazoles with amines in the absence of copper salt, were transformed into 2-aminobenzo[b]chalcogenophenes by the action of potassium carbonate and copper(I) iodide in DMF in different yields.

Polyfluoroalkanols readily reacted with 2-chloro-1,3,2-dioxaphospholanes and 2-chloro-1,3,2-dioxaphosphinanes in hexane in the presence of triethylamine (–10 to 25°C, 5 h) to give 2-polyfluoroalkoxy-1,3,2- dioxaphospholanes and 2-polyfluoroalkoxy-1,3,2-dioxaphosphinanes in 48–72% yield. The products were found to exist as mixtures of cis and trans isomers with the trans isomer predominating for the phospholanes and cis isomer predominating for the phosphinanes according to the ¹H, ¹³C, ¹⁹F, and ³¹P NMR data.

The thermodynamic and kinetic parameters of the cerium(IV) complexes formed in the initial stage of oxidation of dicarboxylic acids (H₂L), like pentanedioic, butanedioic, propanedioic, and ethanedioic acids, by cerium(IV) sulfate were studied by the spectrophotometric and pH-potentiometric methods with the aid of integral kinetic methods at an ionic strength I = 2 mol/L within the pH range of–0.3–1.6 in a sulfuric acid medium and at temperature of 293.15 K. The composition of these complexes, the form of organic ligand existence therein, the thermodynamic parameters of their formation, and the kinetic parameters of their intramolecular redox decomposition were determined. Linear correlations between the found thermodynamic and kinetic parameters of the examined complexes [CeOHL]⁺ were obtained. The rate equation of the redox process occurring in the systems Ce⁴⁺–H₂L was established and the corresponding reaction model was considered.

The methods of synthesis of 4-tert-butyl-5-sulfanylphenyl-and 4-tert-butyl-5-(4'-carboxyphenylsulfanyl) phthalonitriles have been developed and on their basis the corresponding octa-substituted phthalocyanines have been prepared. The effect of the structure of the above phthalocyanine derivatives on their electronic absorption spectra and parameters of thermal degradation in the presence of air oxygen were studied.

A method of synthesis of 4-(1H-benzotriazol-1-yl)-5-[(4-carboxyphenyl)oxy]- and -5-[(4-carboxyphenyl) sulfanyl]phthalonitriles starting with 4-bromo-5-nitrophthalonitriles was developed. The synthesized phthalonitriles were used to prepare cobalt tetra-4-(1H-benzotriazol-1-yl)-tetra-5-[(4-carboxyphenyl)oxy/sulfanyl]phthalocyanines. The spectral and catalytic properties of the resulting octasubstituted phthalocyanines were studied.

The new complexes of xipamide (XPD) with Ti(III), Ni(II), Pd(II), Zr(IV), Ce(IV), and U(VI) have been synthesized. Elemental analysis, magnetic properties, molar conductivities, thermal analysis, and UV-Vis, IR and ¹H NMR spectra, elucidated the structures of complexes. According to spectral data, xipamide behaved in the obtained complexes as a bidentate chelating anion with the charge (–1) and coordinated via oxygen atoms of the deprotonated phenolic and carbonyl groups. Kinetic parameters of thermogravimetric analysys and its differential have been evaluated by using the Coats–Redfern and Horowitz–Metzeger methods. Thermodynamic data indicated thermal stability of all complexes. The ligand and its metal complexes were screened for their antifungal activity against A. fumigatus,G. candidum, syncephalastrum, and C. albicans, and antibacterial activities against two Gram-positive bacteria species, such as S. aureus and B. subtilis, two Gramnegative such as E. coli and P. aeruginosa.

The Buchwald–Hartwig amination reaction between 2-chloro-3-aryl-1,8-naphthyridines and 2-(4-aminophenyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione in the presence of the catalytic system Pd(PPh₃)₄ and the base KO-t-Bu in toluene was studied. The reaction was initiated by microwave irradiation. Highly efficient synthesis has been developed for 2-{4-[(3-aryl-1,8-naphthyridin-2-yl)amino]phenyl}-1H-benzo[de]isoquinoline-1,3(2H)-diones. Structures of the synthesized compounds were evaluated by IR, ¹H and ¹³C NMR spectroscopy. All products were tested for antimicrobial activity against Escheria coli, Bacillus subtilis, Klebsiella pneumoniae, and Staphylococcus aureus.

Abstract—Electronic interactions associated with charge transfer complexes formation of iodine, chloranilic acid (H₂CA) and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) with vitamin B1 have been studied spectrophotometrically. The accumulated data indicated formation of CT-complexes of the general formula [(VB1)(acceptor)_n], (n = 1 or 2). The 1 : 2 and 1 : 1 donor: acceptor molar ratios were calculated on the basis of elemental analysis and photometric titrations. The solid complexes were prepared and characterized by their conductivity, UV-Vis, IR, and ¹H NMR spectra, and thermogravimetric analyses (TGA, DTG). The characteristic physical constants (K_CT, ε_CT, μ, ΔG, I_p, f, E_CT) of the formed CT-complexes were determined to be strongly dependent on nature of the electron acceptors.

A number of novel 3-(1-aryl-1H-1,2,3-triazol-4-yl)-2-(4-fluorophenyl)-1-(2-hydroxy-4-methoxyphenyl) propan-1-ones has been synthesized from 2-(4-fluorophenyl)-1-(2-hydroxy-4-methoxyphenyl)ethanone by its propargylation followed by the click reaction. Structures of all the newly synthesized compounds were characterized by ¹H and ¹³C NMR, and Mass spectra. Their antimicrobial activity was evaluated.

By the reaction of urea, thiourea, sulfanilamide or sulfadimethoxine with tropylium tetrafluoroborate new products of substitution of hydrogen atom by the tropylium motif at the amide nitrogen atom or at the amino group of the benzene ring have been obtained.

9,10-Dioxoanthracenyl-1(2)-diazonium hydrosulfates reacted with pyridine under both the modified Gomberg–Bachmann reaction conditions and in the presence of catalytic amounts of CuCl₂ to form a mixture of isomeric 2-, 3-, and 4-pyridylanthraquinones, of which 2-pyridyl derivatives were isolated in an analytically pure form.

The structure of zinc(II) complexes with 2,2'-bipyridine obtained by a direct synthesis from multicomponent mixtures was studied by the method of X-ray structural analysis. The effects of the ligand environment on the composition of Zn|N_xO_y| coordination unit and on the nature of resulting polyhedra in the synthesized complex compounds were established.