Vol 86, No 1 (2016)

Conditions for the synthesis of nanolayers of cerium and iron binary oxides by the successive ionic layer deposition (SILD) method based on consecutive and repeated realization of redox reactions in a layer of adsorbed Ce³⁺ cations and FeO₄^2– anions on a substrate surface were considered. The synthesized layers were studied by scanning electron microscopy, X-ray spectral microanalysis, IR-Fourier and X-ray photoelectron spectroscopy, and also by X-ray diffraction methods. Under conditions of the synthesis layers of the hydrated amorphous oxide Ce_1.1FeO_x·nH₂O containing Ce(IV) and Fe(III) atoms in the ratio 1.1 : 1.0 are formed on the surface.

The reaction of titanium tetrachloride with diethyl ether at various ratios of components and temperatures was studied by the NMR and mass spectrometry methods. The TiCl₄·2Et₂O complex does not pass in the gas phase. Formation of ethoxytrichlorotitanium among reaction products was established by the X-ray structure analysis. The model of conversion from initial components to titanium dioxide was suggested on the basis of the obtained experimental data and quantum-chemical calculations (B3LYP/def2-SVP level of theory).

The course of the solid-phase synthesis of perovskite-like oxides La_2–xSr_xCoO₄ was studied by the thermal analysis method. It was found that the formation of the oxides begins above 970°С after termination of thermal conversions of initial strontium carbonate and lanthanum oxide, however the final formation of ceramics is in progress up to 1400°С.

The effect of substituents in the reactions of 3,6-di-tert-butyl-о-benzoquinone with organozinc and organocadmium compounds, leading to three types of products: 3-alkyl-6-tert-butyl-о-benzoquinones, 4-alkyl-3,6-di-tert-butyl-о-benzoquinones, and 2-alkoxy-(or 2-phenoxy)-3,6-di-tert-butylphenols. Correlation analysis gave evidence to show that the first- and second-type products are formed by nucleophilic 1,2- and 1,4-addition, while substituted phenols result from single-electron transfer.

Conformational analysis of 5-bromo-5-nitro-1,3-dioxane has been performed by computer simulation in terms of HF/pVDZ, hybrid DFT PBE/3ξ, and RI-MP2/λ2 quantum chemical methods. The global minimum on the potential energy surface corresponds to the chair conformer with axial nitro group, and the other two minima have been identified as chair conformer with equatorial nitro group and 2,5-twist. All transition states on the route of conformational transformations of the title molecule have been revealed.

Reactions of acetoacetanilide with aromatic aldehydes in ethanol at room temperature in the presence of molecular iodine and arylamine afford to 6-aryl-2-methyl-4-oxo-N,N’-diphenyl-2-cyclohexene-1,3-dicarboxamides. The structure of obtained compounds was confirmed by mass spectrometry, IR and NMR spectroscopy data.

Functionally substituted 5-(p-tolyl)isoxazoles and 4,5-dichloroisothiazoles, whose molecules contain azomethine, amino, carboxyl, and ester moieties in various combinations in the aromatic ring in the position 3 of heterocycle, were synthesized. Synthesis of complexes of Pd(II) with carboxyl derivative of 1,2-azoles was performed. They show high catalytic activity in the Suzuki reaction in aqueous media.

The reaction of pentaphenylantimony with 2,4,6-trichlorophenol or bis(2,4,6-trichlorophenoxy)- triphenylantimony in toluene afforded (2,4,6-trichlorophenoxy)tetraphenylantimony. The reaction of triphenylantimony with tert-butyl hydroperoxide and 2,4,6-trichlorophenol led to the formation of bis(2,4,6-trichlorophenoxy) triphenylantimony; further reaction of the latter with triphenylantimony dichloride provided (2,4,6-trichlorophenoxy)triphenylantimony chloride. According to the XRD data, the antimony atoms in the prepared compounds had distorted trigonal-bipyramidal coordination with electronegative ligands in axial positions.

The interaction of 4-tert-butyl-5-nitrophthalonitrile with a series of metal acetates has yielded the corresponding metal phthalocyaninates. The treatment of magnesium tetra(4-tert-butyl-5-nitro)phthalocyaninate with hydrochloric acid has afforded tetra(4-tert-butyl-5-nitro)phthalocyanine. Spectral properties of the prepared macrocycles have been studied. The nature of the organic solvent and the complex forming metal marginally affect the position of the Q band in the electron absorption spectra of the studied compounds. It has been demonstrated that the prepared phthalocyanines can dye polymer materials and are catalytically active towards oxidation of a model sulfur-containing compound.

A comparative analysis of ¹H and ¹³C NMR spectra of 1-(2-ethoxyethyl)-4-(pentyn-1-yl)-4-hydroxypiperidine, 1-(2-ethoxyethyl)-4-(pentyn-1-yl)-4-benzoyloxypiperidine oxalate and their inclusion complexes with β-cyclodextrin was performed. The differences in values of chemical shifts of ¹H and ¹³C nuclei of the substrates and the receptor in the inclusion complexes were determined. It was found that the formation of complexes of 1-(2-ethoxyethyl)-4-(pentyn-1-yl)-4-hydroxypiperidine and 1-(2-ethoxyethyl)-4-(pentyn-1-yl)-4-benzoyloxypiperidine oxalate with β-cyclodextrin was accompanied by insertion of one N-ethoxyethyl fragment of the substrate molecule into the inner sphere of one molecule of the receptor.

Experimental data on the application of metal complexes in radical polymerization of vinyl monomers collected over the recent 15 years have been analyzed and generalized. Special attention has been given to (un)substituted ferrocenes, macrocyclic (clathro)chelates, and iron porphyrinates as well as to the approaches to enhance their catalytic activity in controlled synthesis of macromolecules. The mentioned systems have been compared with each other as well as with selected complexes of other transition metals. It has been shown that the electronic and spatial structures of the metal complexes are related to their efficiency in the radical polymerization reactions.

Copper-catalyzed C–P cross coupling of phosphonate esters with arylboronic acids has been developed. The reaction provided an efficient method for aryl phosphonates under mild conditions.

A series of macrocyclic tripeptides and linear dipeptide Schiff base derivatives has been synthesized using pyridine-3,5-dicarboxylic acid and L-phenyalanine methyl ester as starting materials. Treatment of pyridine-3,5-dicarbonyl dichloride with L-phenylalanine methyl ester gave N,N′-(pyridine-3,5-diyldicarbonyl)bis(L-phenyalanine methyl ester) which was hydrolyzed with 1N sodium hydroxide to the corresponding bis-acid, and the latter was cyclized with diamino acids to afford macrocyclic tripeptide derivatives. The reaction of the bis ester with hydrazine hydrate gave bis-hydrazide, which was condensed with aldehydes to obtain the corresponding Schiff base derivatives. The structures of the newly synthesized compounds were confirmed by IR, ¹H and ¹³C NMR, and MS spectral data and elemental analyses. The antimicrobial activities of some of the newly synthesized compounds were comparable with that of Streptomycin used as control.

Maxacalcitol (1), a kind of active vitamin D drugs, was prepared from pregnenolone acetate (2) using a novel synthetic method including the combination of five-step organic transformations and one-step biological transformation. The new protocol was shorter, milder, and simpler than the reported approaches. The unoptimized overall yield was 0.178%. The structure of all intermediates and final product was confirmed by ¹H NMR, ¹³C NMR and MS techniques.

Two different series of novel analogs of 6,7-aryl/hetaryl coumarins 4a–4h and 8i–8l have been synthesized by using Suzuki–Miyara cross coupling reaction from 4-methyl-2-oxo-2H-chromen-7-yl trifluoro-methanesulfonate and 4-methyl-2-oxo-2H-chromen-6-yl trifluoromethanesulfonate in high yields (70–90%). All synthesized compounds were elucidated by means of IR, ¹H NMR, ¹³C NMR, and MS spectra. The synthesized compounds were tested for antiproliferative activity against different human cancer cell lines (SiHa, MDAMB-231, and PANC-1) and some of products demonstrated the distinctive effect.