Том 60, № 7 (2019)

It is shown on the examples of normal boiling points (T_b) and relative densities of organic compounds from several homologous series that the values of physicochemical properties (A) of simplest homologues can be estimated from those of the adjacent homologues whose molecules differ by one carbon atom. This can be achieved by using simplest recurrent relations A(n) = aA(n ± 1) + b (n is the number of carbon atoms in the molecule; a, b are the coefficients calculated by the least squares method) which are applicable for all sets of various series with the same homologous differences (CN₂ or CF₂). It is shown that the estimations based on the data obtained from “zero” or first homologues containing only hydrogen atoms or methyl groups in their molecules are 3-4 times less exact than those obtained for the homologues with larger numbers of carbon atoms in the molecule. This is explained by objective anomalies common to the properties of simplest homologues of all series and caused, among other reasons, by structural factors. A method is proposed to offset the anomalies in T_b values of the first members of the series using additive corrections.

Initial stages of HgCdTe oxidation in a glow discharge plasma in O₂ atmosphere are first studied using the XPS method. The chemical composition of the growing native oxide layer is investigated and the oxidation kinetics is revealed. It is experimentally established that the mechanism of HgCdTe oxidation changes as the oxide thickness reaches 2-3 nm due to the change of the limiting stage of the chemical reaction. The composition of the formed oxide is varies with depth and is characterized by low mercury content. It is suggested that the diffusion of oxygen to the oxide–semiconductor interface and its predominant interaction with tellurium are the main mechanism of the native MCT oxide growth, so that the oxide region bordering the substrate is ∼10% oxygen depleted. The obtained results are discussed and compared with previously reported data on MCT oxidation in RF plasma and in liquid electrolytes.

A series of four isostructural double complex salts are prepared on the basis of [M¹(NH₃)₆]³⁺ cations and [M²(C₂O₄)₃]^3– anions, where M¹ = Co, Ir, M² = Fe, Cr. The salts are crystallized in a hexagonal space group P3̄c1. According to thermal analysis data, thermal stability in an atmosphere of argon (starting temperature of the decomposition of dehydrated products) of studied compounds depends on the nature of the complex tris-oxalate anion and increases in the series [M¹(NH₃)₆][Co(C₂O₄)₃] < [M¹(NH₃)₆][Fe(C₂O₄)₃] < [M¹(NH₃)₆][Cr(C₂O₄)₃] < [M¹(NH₃)₆][Ir(C₂O₄)₃] (M¹ = Co, Ir). Hexammineiridium(III) salts are more stable than cobalt(III) salts with the same anion. Thermal decomposition of [Co(NH₃)₆][Fe(C₂O₄)₃]·3H₂O and [Ir(NH₃)₆][Fe(C₂O₄)₃]·3H₂O salts in an atmosphere of hydrogen leads to the formation of solid solutions Co_0.5Fe_0.5 and Ir_0.5Fe_0.5, respectively.

The bis(oxalate) complex of niobium (NH₄)[NbO(C₂O₄)₂(H₂O)₂]·3H₂O can be dissolved in DMF on heating. Ether diffusion into this solution in the presence of Et₄NBr leads to the formation of colorless crystals of (Et₄N)₄[Nb₂O₂(C₂O₄)₄(μ-C₂O₄)] (1). The characterization of the obtained compound by single crystal and powder XRD, IR and Raman spectroscopy, and elemental analysis allows to clarify processes occurring with the bis(oxalate) niobium complex in aqueous solutions.

Molecular and crystal structures of mononuclear lanthanide (Ln) compounds with the 3,6-di(tert-butyl)-1,2-benzoquinone (SQ) radical anion of the composition [Ln(SQ)₃(THF)₂] (Ln = Pr, Nd, Eu, Tb, Dy), [Ln(SQ)₃(Q)], (Ln = Gd, Eu; Q – 3,6-di(tert-butyl)-1,2-benzoquinone), [La(SQ)₃(Q)(THF)], [Ce^IV(SQ)₄], [NaLn(SQ)₄(THF)₃]·0.25C₆H₁₄ (Ln = Gd, Tb), [NaLn(SQ)₄(Q)(THF)] (Ln = La, Pr) are determined. The study of the magnetic properties of isolated heterospin solid phases reveals that intramolecular antiferromagnetic exchange interactions between unpaired electrons of SQ moieties dominate in them. At T≤2 K [Dy(SQ)₃(THF)₂] exhibits the properties typical of a metamagnetic compound.

Three aliphatic ligands are synthesized and fully characterized by IR, ¹H and ¹³C NMR spectroscopy. These ligands react with a zerovalent compound Pd(dba)₂ in the presence of methallyloxytris(dimethylamino) phosphonium hexafluorophosphate salt [C₄H₇OP(NMe₂)₃]⁺\({\rm{PF}}_6^-\) as an allylating agent for the synthesis of cationic η₃-methallylpalladium complexes to give three cationic mononuclear η₃3-methallylpalladium complexes in high yields. These formed complexes are characterized by IR, ¹H NMR and ¹³C NMR spectroscopy. One of them is characterized by X-ray diffraction. A DFT-optimized structure is also discussed.

A paddle-wheel copper(II) carboxylate complex of the type [Cu₂(2-nb)₄(EtOH)₂] (1), where 2-nb = 2-nitrobenzoate, is synthesized and characterized by single crystal X-ray diffraction, IR spectroscopy, and elemental analysis. The results show that the complex has a square pyramidal geometry around the metal center. Combustion of copper(II) carboxylate gives copper(II) oxide nanoparticles which were characterized by powder XRD, SEM, EDX, and IR analyses. This study indicates that the coordination compound represents a suitable single precursor for the synthesis of CuO nanoparticles.

The 1,2,3,4-tetrahydroisoquinoline derivative compound fused with thiophene (BDTTIQ) is synthesized by the slow evaporation solution growth method and characterized by SCXRD, ¹H and ¹³C NMR techniques. In the synthesized compound, the tetrahydroisoquinoline fragment of BDTTIQ is almost in the half-chair conformation. A 3D supramolecular architecture is attained by intermolecular C-H...0 and C-H...71 interactions in the crystal structure. Molecular docking simulations are carried out to examine the inhibitory nature of the synthesized compound BDTTIQ against ARK1C3 protein.

A monomeric ternary complex [Cu(tmen)(mef)₂] (1) (where mef = mefenamate anion (C₁₅H₁₅NO₂¹⁻, tmen = N,N,N′,N′-tetramethylethylenediamine) is prepared by the reaction of CuCl₂·2H₂O, mefenamic acid (mefH = 2-(2,3-dimethylphenyl)aminobenzoic acid), and N,N,N′,N′-tetramethylethylenediamine (tmen) in the presence of sodium hydroxide. Complex 1 is characterized by the elemental combustion analysis, UV-visible and FT–IR spectroscopy, thermal analysis, and single crystal X-ray diffraction. From the crystal structure of complex 1, it is evident that each copper(II) ion is six-coordinate and is bonded to chelating tmen, and four O atoms of two mef anions (mef^1–). In the crystal, the intramolecular hydrogen bonding exists between the H atom of the –NH group of mef and the O atom of one of the coordinated carboxylate O atoms, belonging to the same mef ligand. Complex 1 is tested for antibacterial properties against four strains, including Staphylococcus aureus, Bacillus spizizenii, Escherichia coli, and Klebsiella pneumonia. The complex shows a biological activity against Staphylococcus aureus and Bacillus spizizenii.

Heterocyclic compound 1-((2S,3S)-2-(benzyloxy)pentan-3-yl)-4-(4-(4-(4-hydroxyphenyl)piperazin-1-yl)phenyl)-1H-1,2,4-triazol-5(4H)-one (1) designed using 4-(4-(4-aminophenyl)piperazin-1-yl)phenol (2) and (S)-N′-(2-(benzyloxy)propylidene)formohydrazide (3) as start materials is successfully obtained via a multistep synthesis and finally characterized by IR, ¹H NMR, and single crystal X-ray diffraction. In addition, the in vitro anticancer activities of newly synthesized compound 1 are evaluated against three human bone cancer cell lines U2OS, Saos-2, and GC9811. In addition, the molecular docking is used to study the potential antiviral activity of 1 by calculating the binding sites for the 1AS0 protein.