卷 86, 编号 11 (2016)

Regularities of formation of complex aluminates with structure of P/RS intergrowth type phases in the Ln₂O₃–MO–Al₂O₃ systems (Ln = rare-earth element, M = Mg, Ca, Sr, Ba) have been considered. Systematization of the data on formation of complex compounds coexisting with one-layer phases in the Ln₂O₃–MO–Al₂O₃ systems and analysis of geometry criteria of LnMAlO₄ stability is a promising approach to prediction of novel compounds with structure of Ruddlesden–Popper phase.

Pyridine catalyzes oxidation of alcohols with 4-acetamido-2,2,6,6-tetramethylpiperidine-1-oxyl–iodine catalytic system at room temperature. Symmetric esters are formed in good yields.

Reactions of acetoacetic acid N-arylamides with aromatic aldehydes and urea led to the formation of N,6-diaryl-4-methyl-2-oxo-1,2,3,6-tetrahydropyrimidine-5-carboxamides. Structure and antimicrobial activity of the compounds obtained were examined.

The reactions of chloroethynylphosphonates with aromatic secondary aminomalonates occur as classic nucleophilic substitution of chlorine atom at the sp-hybridizied carbon atom to form new phosphorylated 2-arylaminomalonates, diethyl esters of 2-(diethoxyphosphorylethynyl)-2-arylaminomalonic acids. Nonobservance of chemo- and regioselectivity was revealed when using cyclohexyl- and benzylaminomalonates.

Reaction of ethyl 2-bromomethyl-5-(1,2,3-thiadiazol-4-yl)furan-3-carboxylate with nucleophiles of different nature was studied. It is shown that substitution of bromine with acetoxy group takes place under the action of sodium acetate in the acetic acid. Stronger bases, like phenolates, cause considerable decomposition of the labile furylthiadiazole fragment Decomposition can be avoided only when this reaction is carried out in the presence of a phase transfer catalyst under the conditions of the ion pair extraction,. In the reaction with sodium N,N-diethyl dithiocarbaminate the corresponding thioester is formed. Butanethiol and thiophenol are alkylated as potassium thiolates. In the last case S-alkylation proceeds exclusively. Reaction with excess 2-aminoethanol permits to prepare secondary amine, and the reactions with pyrrolidine, piperidine, and morpholine give the corresponding tertiary amines. Phosphorylation with triethyl phosphite under the conditions of Arbuzov reaction leads to the corresponding diethyl phosphonate. In all these transformations furylthiadiazole fragment is retained.

Metal-promoted nucleophilic addition of primary amino group of a natural L-amino acid anchored on polystyrene support to coordinated isonitrile substrate has afforded preparation and simultaneous immobilization of chiral acyclic diaminocarbene complex of palladium(II). The obtained catalytic system is stable under conditions of the Suzuki reaction and demonstrates good catalytic activity in the reaction with a sterically hindered substrate.

Novel organic compounds of antimony(V), tris(2,6-dimethoxyphenyl)antimony diisocyanate and oxide, have been prepared and studied by X-ray diffraction analysis. Antimony atoms in the diisocyanate molecule and in two symmetrically independent molecules of the oxide exhibit trigonal-bipyramidal and tetrahedral coordination, respectively.

4,5-Bis[4-(1-methyl-1-phenylethyl)phenoxy]phthalonitrile was prepared by the nucleophilic substitution of the nitro group and bromine in 4-bromo-5-nitrophathalonitrile. The product was used to synthesize the corresponding octasubstituted phthalocyanine, as well as its magnesium, copper, zinc, cobalt, and nickel complexes. The spectral properties of the synthesized phthalocyanines were studied.

DFT calculations with B3LYP and PBE0 functionals have been carried out to determine the structural parameters, vibrational frequencies, and quadrupole moments of double-decker heavy lanthanide phthalocyaninates Pc₂Lu, (Pc₂Lu)⁺, (Pc₂Lu)^–, Pc₂Yb, (Pc₂Yb)⁺, and (Pc₂Yb)^–. Free valence of the Pc moiety [0.5 in Pc₂Lu and Pc₂Yb; 1.0 in (Pc₂Lu)⁺ and (Pc₂Yb)⁺] is delocalized in small fractions over the carbon atoms. The Pc₂Lu и Pc₂Yb molecules have a high electron affinity (3.2 eV) and a low ionization potential (6.1–6.3 eV). Calculations predict formation of quadruple-decker supercomplex Yb(Pc₂Lu)₂ from two Pc₂Lu molecules and an Yb atom via an exothermic process. The equilibrium structure of the molecules and ions can be characterized by D_4d point symmetry group.

By means of computer modeling, the main regularities of the interaction of triterpene saponins with chitosan are revealed. It is shown that the sorption of glycosides changes the ordered configuration of chitosan, and the complex of chitosan with saponin, the derivative of quillaic acid, is more stable than the complex with the derivative of oleanolic acid. The formation of complexes occurs due to electrostatic, hydrophobic interactions, and hydrogen bonds, whose strength is determined by the nature, geometry, and specific structure of terpenes of the β-amyrin series.

The effect of the copper sulfate, hydrazine, and gelatin concentrations, as well as of the Bloom strength of gelatin, pH, and synthesis temperature on the formation of copper nanoparticles via copper(II) sulfate reduction with a hydrazine solution has been evaluated. Conditions for the formation of oxidation- and aggregation-resistant concentrated (up to 0.4 M) copper metal hydrosols have been found. According to the transmission electron microscopic data, the resulting hydrosols contain metallic copper nanoparticles shaped as polyhedra with six poorly defined facets, having an average size of 30–60 nm, stabilized by a gelatin layer (2–3 nm).