Том 86, № 8 (2016)

Results of carbon nanoribbons and nanotubes simulation by means of hybrid density functional method and using empirical potentials have been compared. Energy of the nanoribbons formation and their citting from graphene sheet as well as energy of the nanotubes folding from graphene and nanoribbons have been determined. The REBO force field satisfactorily reflects the result of quantum chemical simulations; however, it cannot reproduce the formation of triple bonds between the edge atoms of the nanoribbons in the armchair conformation and thus leads to underestimated stability of the latter. Energy of the nanotubes folding from the nanoribbons is linear with the nanotube diameter.

Thin films of indium(III) sulfide have been prepared by chemical precipitation from aqueous solutions containing indium(III) nitrate, thioacetamide, tartaric acid, and hydroxylamine hydrochloride at 333–368 K. Kinetics of In₂S₃ precipitation and the films growth under conditions of spontaneous formation of the solid phase in the solution has been studied. Formal rate law of indium(III) sulfide formation accounting for the partial orders of In₂S₃ precipitation with respect to the system components and the process activation energy has been derived. The effects of the reaction mixture composition, temperature, and the synthesis duration of In2S3 films growth have been studied.

Magnesium silicates modified with 13(1)-N-methylamide-17-methyl-15-diethylene glycol ester of chlorin е₆ have been prepared for the first time via heat treatment. The studies by means of X-ray diffraction analysis, scanning electron microscopy, differential scanning calorimetry, and thermogravimetric analysis have revealed that variation of the synthesis conditions affords products differing in the size, particles morphology, and chlorin concentration.

Mechanism of catalytic selective oxidation of aliphatic thiols RSH into disulfides R₂S₂ has been suggested basing on quantum-chemical DFT simulation (M06/Def2-TZVP) of coordination compounds of d-elements and using the principle of complementarity. The active center of the catalytic system is a binuclear fragment {M(m-OH)₂M′}ⁿ⁺ formed due to hydrolysis of the starting mononuclear d-element compound. The catalysts based on Pd(II) and Pt(II) binuclear active centers are spatially similar throughout the process. The chief interrelated functions of the binuclear catalysts are spatial approaching of two thiolate anions RS^– in the inner sphere of the bridged coordination compound required for the disulfide (–S–S–) cross-linking and providing for two-electron redox transfer during the transformation of these anions into disulfide (СH₃)₂S₂.

Reactions of 3,4-dihydroxyhexa-2,4-diene-1,6-dioic acid esters with anthranilic acid hydrazide lead to the formation of 3,4-bis(2-aminobenzoylhydrazono)hexane-1,6-dioic acid esters. Structural features of the synthesized compounds are discussed.

2-Substituted 1,3,4-thiadiazole-5-thiol has been synthesized basing on hydrazide of 3-methoxy-phenoxyacetic acid. Methods of SH-alkylation, aminomethylation, and cyanoethylation of the product have been elaborated. Reactions of the starting hydrazide leading to 4-amino-3,5-substituted 4Н-1,2,4-triazoles and acyl hydrazides of dicarboxylic acids containing pharmacophore groups in the molecule have been studied.

The approaches to synthesis of 1-phenyl-1-halo-1-silacyclohexanes C₅H₁₀Si(Ph)X (X = F, Cl, Br) have been examined. 1-Phenyl-1-chloro-1-silacyclohexane has been prepared via the known reaction of phenyltrichlorosilane with dimagnesium derivative of 1,5-dibromopentane; up to 20% of 1-bromo-1-phenyl-1-silacyclohexane admixture is formed along with the target product. The minor product formation has been prevented using an alternative method of chlorination of 1-phenyl-1-silacyclohexane with N-chlorosuccinimide. 1-Phenyl-1-fluoro-1-silacyclohexane has been obtained in close to quantitative yield via the reaction of 1-phenyl-1-chloro-1-silacyclohexane with SbF₃ and in 70% yield via its reaction with HF. The synthesis of 1-phenyl-1-bromo-1-silacyclohexane via bromination of 1-phenyl-1-chloro-1-silacyclohexane with N-bromosuccinimide has given the target product as a minor one, the major product being disiloxane formed due to hydrolysis of the Si–Br bond.

Methoxymetyl derivatives of furoylphosphonates react with ethoxymethylenetriphenylphosphoranes to give phosphorylated (methoxymethylfuryl)acrylates. The reaction proceeds stereoselectively: phosphoryl and ester groups at the double bond are always trans-located. Treatment with dichloromethylmethyl ether and catalytic amount of zinc chloride converts the methoxymethyl group in the synthesized compounds into chloromethyl one. The ester group and the double bond are inert under these conditions.

The reaction of alginic acid with acrylamide in water in the presence of alkali and in dioxane in the presence of tetramethylammonium hydroxide has been studied. The effects of the acrylamide excess, reaction duration, and the alkali concentration on the amount of ethylamide and ethylcarboxyl units in the product have been elucidated.

The interaction of tris(4-fluorophenyl)antimony with copper(II) bromide in acetone has afforded tris(4-fluorophenyl)antimony dibromide; recrystallization of the product from ethanol has yielded the (4-FC₆H₄)₃SbBr₂·[(4-FC₆H₄)₃SbBr]₂O adduct. [(4-FC₆H₄)₃SbCNS]₂O oxide has been prepared from tris(4-fluorophenyl)antimony dibromide and potassium thiocyanate in aqueous-acetone solution. Antimony atoms in the molecules of the prepared compounds exhibited the distorted trigonal bipyramid coordination with the electron-accepting ligands in the axial positions.

The coordination of meso-tetraphenyltetrabenzoporphyrin and metal exchange of its Cd(II) complex with manganese(II) chloride and acetate in DMF and a chloroform–methanol mixture have been studied by spectrophotometry. The Mn(III) chloride and acetate acido complexes formed in these reactions have been isolated and characterized. The dissolution of the synthesized complexes in DMF in the presence of solid KOH gives Mn(II) meso-tetraphenyltetrabenzoporphyrinate.

Nickel(II), copper(II), and zinc(II) complexes with the Schiff base obtained from isonitroso-2-acetylnaphthalene and 1,2-phenylenediamine were synthesized. The compounds were characterized by elemental analyses, FT-IR, UV-Vis, and ¹H and ¹³C NMR spectra, conductance measurements, magnetic susceptibility measurements, and thermal analysis. The results suggest tetradentate coordination of the symmetrical Schiff base ligand through the two oxime oxygen atoms and two azomethine nitrogen atoms. The molar conductance data showed that the synthesized complexes are non-electrolytes.

A practical, efficient and inexpensive method of synthesis of iodopyrazoles by the reaction of pyrazoles with iodine using n-butyltriphenylphosphonium peroxodisulfate as an oxidant at room temperature is reported. The use of n-butyltriphenylphosphonium peroxodisulfate is feasible due to its easy preparation and handling, high stability and activity.

2-Dimethylamino methylenechromanone 1 reacted with 4H-1,2,4-triazol-3-amine in acetic acid to give only one isolated product which was identified by X-ray study as 6H-chromeno[3,4-e][1,3,4]triazolo[2,3-a]-pyrimidine. The molecular structure of 3, C₁₂H₈N₄O, was determined to be monoclinic, P2₁/c, a = 16.3875(5), b = 8.8378(3), c = 13.8392(5) Å, β = 101.190(1)°, V = 1966.22(11) ų, Z = 8.