Showing papers in "Russian Journal of General Chemistry in 2014"
TL;DR: The results of Russian and foreign studies on the process of eutrophication of water bodies are summarized in this paper, where the main sources of export of nutrients in water bodies with catchment areas are discussed.
Abstract: The results of Russian and foreign studies on the process of eutrophication of water bodies are summarized. The main sources of export of nutrients in water bodies with catchment areas are discussed in the article. The toxins produced by blue-green algae and their effects on organisms are considered. Critical total phosphorus loads are estimated for some lakes of the Russian Federation and five largest lakes of China.
33 citations
TL;DR: In this paper, the theoretical possibility to create drug delivery systems on the basis of detonation nanodiamonds and the promise of such systems hold for commercialization and practical application are discussed.
Abstract: Analysis of published and author’s own experimental data provides convincing evidence for the theoretical possibility to create drug delivery systems on the basis of detonation nanodiamonds and for the promise such systems hold for commercialization and practical application.
29 citations
TL;DR: In this paper, the properties of the pilocarpine (Pil) drugs and chloranilic acid (CLA) have been studied with XRD and SEM techniques, and the reported complexes exhibited a specific electronic spectrum with a strong, broad absorption band with much longer wavelength than those typical for the individual reagents.
Abstract: Study of the charge-transfer or proton-transfer interaction of drugs is important for understanding the drug-receptor interactions and the mechanism of drug action. In the current research the corresponding data were accumulated in the course of synthesis and study of the H-bonded complexes originated from the interaction between procaine (Pro) or pilocarpine (Pil) drugs and chloranilic acid (CLA). The targeted microstructure products have been isolated and characterized by elemental and spectral (electronic and vibrational) data. Microstructural properties of the reported complexes were studied with XRD and SEM techniques. The Pil drug containing complex exhibited a specific electronic spectrum with a strong, broad absorption band with much longer wavelength, λmax, than those typical for the individual reagents. It is noteworthy that the complex had good crystallinity. Application of Debye-Scherrer equation indicated that the reported complexes were in the range of nanosize.
25 citations
TL;DR: In this article, the complexation properties of Guaifenesin with two types of acceptors: σ-acceptor (i.e., iodine) and π-acceptors (e.g., dichlorodicyanobenzoquinone, chloranil and picric acid).
Abstract: The present study deals with the complexation properties of Guaifenesin with two types of acceptors: σ-acceptor (i.e., iodine) and π-acceptors (i.e., dichlorodicyanobenzoquinone, chloranil and picric acid). All the prepared complexes were characterized stoichiometrically and structurally using various spectral techniques, as well as elemental analyses. Thermal decomposition behavior of complexes was studied, and their thermodynamic parameters were calculated using Coats-Redfern and Horowitz-Metzger equations. It has been found that the complexation with PA and CHL acceptors increases the values of enthalpy and entropy, while the complexation with DDQ and iodine acceptors decreases the values of these parameters compared with the free GU donor.
24 citations
TL;DR: Intermolecular charge transfer complexes (CT) between the tris(hydroxymethyl)methane (THM) as a donor and picric acid (PA), chloranilic acid (CLA) and 1,3-dinitrobenzene (DNB) as π-acceptor have been structurally, thermally and morphologically studied in methanol at room temperature.
Abstract: Intermolecular charge-transfer complexes (CT) between the tris(hydroxymethyl)methane (THM) as a donor and picric acid (PA), chloranilic acid (CLA) and 1,3-dinitrobenzene (DNB) as a π-acceptor have been structurally, thermally and morphologically studied in methanol at room temperature. Based on elemental analyses (CHN), the stoichiometry of the obtained CT complexes (THM: acceptor molar ratios) was determined to be 1 : 1 for all three complexes. The CT complexes have been characterized via elemental analyses (CHN), IR, Raman and 1H NMR spectroscopy in order to predict the position of the CT interaction between the donating and accepting sites. Thermal decomposition behavior of these complexes was also investigated, and their kinetic thermodynamic parameters were calculated with Coats-Redfern and Horowitz-Metzger methods. Finally, the microstructure properties of these complexes were observed using scanning electron microscope (SEM).
24 citations
TL;DR: In this paper, cobalt ferrite layered double hydroxide (LDH) nanoparticles with cubic structure were synthesized by the co-precipitation method: addition of NaOH solution to a solution of Co2+ and Fe3+.
Abstract: Cobalt ferrite layered double hydroxide (LDH) nanoparticles with cubic structure were synthesized by the co-precipitation method: addition of NaOH solution to a solution of Co2+ and Fe3+. Formation of nanoparticles was confirmed by XRD, SEM, TEM, PSA, FT-IR, TGA, DSC, and magnetic characteristics were measured using VSM. Crystals produced by calcination at 900°C possessed high coercivity and pronounced physical and chemical stability. Nanoparticles of CoFe2O4 formed outer layers with poor crystallization on the surface of cobalt ferrite nanocrystals.
23 citations
TL;DR: In this article, the synthesis and application of cocrystal pharmaceutical systems is described. The solubility and bioavailability of such systems are several orders of magnitude higher than those for the individual compounds and much higher than the respective parameters attainable by other technologies.
Abstract: The new technology of enhancement of the solubility of poorly soluble drug substances is based on the synthesis and application of cocrystal pharmaceutical systems. The solubility and bioavailability of such systems are several orders of magnitude higher than those for the individual compounds and much higher than the respective parameters attainable by other technologies.
22 citations
TL;DR: In this paper, a metal complex luminophor with long-chain alkyl substituent in the 5-aryl fragment was obtained, and its beryllium complex III was prepared as well.
Abstract: Metal chelates with 2-hydroxyphenyloxadiazole are widely used in development of organic light emitting diodes (OLEDs) as photoand electroluminescent materials [1, 2]. However, most of them are poorly soluble in organic and aqueous-organic media, banning the modern high-performance and low-cost technologies such as spin-coating or ink-jet printing in the OLEDs production [3]. In order to obtain highly soluble metal complex luminophors, we prepared 2-(2'hydroxyphenyl)-5-(4''-nonylphenyl)-1,3,4-oxadiazole II, containing long-chain alkyl substituent in the 5-aryl fragment that increased solubility of the product in organic medium; its beryllium complex III was prepared as well. N-Aroylhydrazide I obtained via benzoylation of salicylhydrazide was cyclized with thionyl chloride to form oxadiazole II. The latter reacted with BeSO4·4H2O in the presence of alkali to give the complex III in good yield. DOI: 10.1134/S1070363214010290
20 citations
TL;DR: Triarylantimony(V) catecholate complexes were synthesized by the oxidative addition of 3,6-di-tert-butyl-4,5-dimethoxy-o-benzoquinone to triarylstibines as discussed by the authors.
Abstract: Triarylantimony(V) catecholate complexes were synthesized by the oxidative addition of 3,6-di-tert-butyl-4,5-dimethoxy-o-benzoquinone to triarylstibines. The electrochemical properties and antiradical activity of the synthesized compounds were studied. According to cyclic viltammetry data, the complexes are oxidized via two consecutive quasi-reversible stages. Introduction of halogen atoms in para-position of phenyl groups at Sb(V) causes anodic shifts of the oxidation potentials and enhances stability of the mono- and dicationic forms of the compounds, which form in the course of electrochemical transformations. Triarylantimony(V) catecholate complexes exhibit appreciable antiradical activity in the auto-oxidation of oleic acid. In was found that the inhibitory activity of the complexes depends on their redox potential.
17 citations
TL;DR: In this article, a simple and efficient method of Friedel-Crafts acylation of arenes with succinic anhydride, phthalic anhydrides, and glutaric anhdrides under the action of 1-butyl-3-ethylimidazolium ([bmim]Br/AlCl3 ([bim]+) cation (ionic liquid) and ultrasound irradiation is presented.
Abstract: A simple and efficient method of Friedel-Crafts acylation of arenes with succinic anhydride, phthalic anhydride and glutaric anhydride under the action of 1-butyl-3-ethylimidazolium ([bmim]Br/AlCl3 ([bmim]+) cation (ionic liquid) and ultrasound irradiation is presented. Thy purity of products was tested by GC-MS and their structures evaluated by IR and 1H NMR spectroscopy.
16 citations
TL;DR: Sulfo derivatives of cobalt phthalocyanine containing naphthalene fragments have been synthesized, and their self-association and molecular complexation with pyridine in aqueous solution have been studied by spectrophotometry as mentioned in this paper.
Abstract: Sulfo derivatives of cobalt phthalocyanine containing naphthalene fragments have been synthesized, and their self-association and molecular complexation with pyridine in aqueous solution have been studied by spectrophotometry. The dissociation constants of the dimeric associates have been determined. The effects of the number of functional groups in the peripheral substituents and of the axial ligand on the phthalocyanine dimerization process have been revealed.
TL;DR: In this paper, a series of new (E)-1-aryl-3-[2-(piperidin-1-yl)quinolin-3-yl]prop-2-en-1ones have been efficiently prepared via the Claisen-Schmidt condensation of aryl methyl ketones under conditions of ultrasound and microwave irradiation.
Abstract: Series of new (E)-1-aryl-3-[2-(piperidin-1-yl)quinolin-3-yl]prop-2-en-1-ones and (E)-1-aryl-3-[2-(pyrrolidin-1-yl)quinolin-3-yl]prop-2-en-1-ones have been efficiently prepared via the Claisen-Schmidt condensation of 2-(piperidin-1-yl)quinoline-3-carbaldehyde and 2-(pyrrolidin-1-yl)quinoline-3-carbaldehyde, respectively, with aryl methyl ketones under conditions of ultrasound and microwave irradiation. Structures of the products have been confirmed by IR, 1H NMR, 13C NMR, and mass spectroscopy, as well as by elemental analysis. Evaluation of the in vitro antibacterial activity against bacterial (Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli) and fungal (Aspergillus niger and Candida metapsilosis) strains has revealed good antimicrobial activity of some of the tested compounds.
TL;DR: In this paper, a variable composition based on zirconium dioxide was synthesized in the ZrO2-Y2O3-H2O systems under hydrothermal conditions.
Abstract: We synthesized nanoparticles of variable composition based on zirconium dioxide in the ZrO2-Y2O3 (or Gd2O3)-H2O systems under hydrothermal conditions. By X-ray diffraction and small-angle X-ray scattering studies revealed that the nanoparticles consist of crystalline core and amorphous shell. Increase of Y2O3 (or Gd2O3) content yields increases of shell size and decreases of core size. The effect is due to suppressed ZrO2 crystallites growth caused by development of the shell preventing zirconium ions transport.
TL;DR: In this paper, the Suzuki reaction was used to synthesize 1-(Naphth-1-yl)- and 1-(1,1′-biphenyl)-4-yl-3,4,4-trichloro-3-butenoyl chloride.
Abstract: 1-(Naphth-1-yl)- and 1-[(1,1′-biphenyl)-4-yl-3,4,4-trichloro-3-buten-1-ones were synthesized by acylation of naphthalene and biphenyl with 3,4,4-trichloro-3-butenoyl chloride. Further reaction with hydroxylamine led to 5-(naphth-1-yl)- and 5-[(1,1′-biphenyl)-4-yl]isoxazole-3-carbaldehyde oximes. The latter form complexes with palladium, which possess high catalytic activity in the Suzuki reaction in aqueous and aqueous-alcoholic media.
TL;DR: In this paper, the reaction of hydrogen fluoride fed from the air side of the air/LaCl3 aqueous solution interface with lanthanum cations was studied, and the reaction yields a 0.5-1.5μm LaF3·nH2O surface film with hexagonal crystal structure, built of the ordered planar LaF 3 nH 2O nanocrystals.
Abstract: We present the first study of the reaction of hydrogen fluoride fed from the air side of the air/LaCl3 aqueous solution interface with lanthanum cations. The reaction yields a 0.5–1.5-μm LaF3·nH2O surface film with hexagonal crystal structure, built of the ordered planar LaF3·nH2O nanocrystals (the crystal thickness of 7–15 nm and surface area of 0.5–2.5 μm2). The nanocrystals are oriented perpendicular to the interphase boundary, and their packing gets looser towards the solution side of the film. Upon drying in air, the LaF3·nH2O film rolls up to form microtubes 20–100 μm in diameter and up to 2 mm long. The microtubes are likely formed due to the contraction forces developing upon drying in the lower, loosest part of the wet film.
TL;DR: In this paper, the authors studied membrane transport properties towards alkali metal ions of sinergetic mixtures of organophosphorus carries, N,N-bis(dihexylphosphorylmethyl)octylamine and didecylthiophophorus or didecyldithiophorus acids.
Abstract: We have studied membrane transport properties towards alkali metal ions of sinergetic mixtures of organophosphorus carries, N,N-bis(dihexylphosphorylmethyl)octylamine and didecylthiophosphorus or didecyldithiophosphorus acids. The influence of main parameters of extraction (pH of the feed phase as well as concentration and ratio of the carriers in the membrane) on the membrane transport rate and selectivity with respect to lithium has been analyzed. Conditions of efficient and selective (to separate K+ and Na+) membrane extraction of Li+ have been established. Advantages of the studied systems in comparison with some previously known ones are demonstrated.
TL;DR: In this article, a new scheme of oxidative polymerization of p-phenylenediamine was suggested, which yields not a polyquinoxaline polymer as described in the literature but a modified poly(1,4-benzoquinonediimine-N,N′-diyl-1, 4-phenylene) analogous to polyaniline known as pernigraniline.
Abstract: Oxidative polymerization of p-phenylenediamine in a hydrochloric acid solution yields not a polyquinoxaline polymer as described in the literature but a modified poly(1,4-benzoquinonediimine-N,N′-diyl-1,4-phenylene) analogous to polyaniline known as pernigraniline. A new scheme of oxidative polymerization of p-phenylenediamine was suggested.
TL;DR: Colloid particles of metals of varying valence are found to be relatively cheap and easily prepared catalyst permitting the the hydrogenation under mild conditions as mentioned in this paper, and the reduction of unsaturated compounds with gaseous hydrogen at atmospheric pressure and low temperature has been developed Colloid solutions of metals from the series iron, nickel, cobalt, chromium, manganese or their mixtures were prepared in situ directly in the reaction mixture.
Abstract: Colloid particles of metals of varying valence are found to be relatively cheap and easily prepared catalyst permitting the the hydrogenation under mild conditions Procedure of reduction of unsaturated compounds with gaseous hydrogen at atmospheric pressure and low temperaturehas been developed Colloid solutions of metals from the series iron, nickel, cobalt, chromium, manganese or their mixtures were prepared in situ directly in the reaction mixture Selective the hydrogenation of multiple carbon-carbon bonds without the reduction of a series of functional groups was observed
TL;DR: In this paper, an energy model for the formation of nanotubes and nanoscrolls from thin sheets was constructed and two major factors responsible for rolling up were identified: size misfit of the crystal lattices forming the sheet and different surface energies on its opposite sides.
Abstract: An energy model for the formation of nanotubes and nanoscrolls from thin sheets was constructed. Two major factors responsible for rolling up were identified: size misfit of the crystal lattices forming the sheet and different surface energies on its opposite sides. An optimal cross-sectional geometry was calculated for chrysotile nanotubes. The influence of major physical parameters (Young’s modulus and difference in surface energies) on the nanotube radius was considered.
TL;DR: In this paper, the effect of fullerene fragment on pyridine fragments coordination has been considered and the reaction proceeds via two stages: rapidly established equilibrium between the reactants and their molecular complex 1: 1 [K = (1.97 ± 0.52) × 104 L/mol] followed by slow irreversible displacement of hydroxy group into the second coordination sphere to form cationic outer sphere complex (k = 0.26 L s−1 mol−1).
Abstract: Interaction between hydroxyoxo(5,10,15,20-tetraphenylporphyrinato)molybdenum(V) and 2′-(pyridin-4-yl)-5′-(pyridin-2-yl)-1′-(pyridin-2-yl)methylpyrrolidinyl[60]fullerene in toluene has been studied by means of spectrophotometry. The reaction proceeds via two stages: rapidly established equilibrium between the reactants and their molecular complex 1: 1 [K = (1.97 ± 0.52) × 104 L/mol] followed by slow irreversible displacement of hydroxy group into the second coordination sphere to form cationic outer sphere complex (k = 0.26 L s−1 mol−1). The effect of fullerene fragment on pyridine fragments coordination has been considered.
TL;DR: In this article, the interaction of copper, lanthanum, thallium and mercury salts solutions with an inorganic ion exchanger "polysurmin" was investigated, and it was shown that polysurmin adsorbs the ions of these metals and exhibits specific selectivity for Hg2+ ions demonstrating abnormally high capacity.
Abstract: Interaction of copper, lanthanum, thallium and mercury salts solutions with an inorganic ion exchanger “polysurmin” was investigated. It was shown that the ion exchanger adsorbs the ions of these metals and exhibits specific selectivity for Hg2+ ions demonstrating abnormally high capacity.
TL;DR: In this article, structural parameters of the nearest surrounding of nitrate and perchlorate ions in aqueous solutions under standard conditions have been discussed and compared, including hydration numbers, interparticle distances, and ionic association types.
Abstract: Data on structural parameters of the nearest surrounding of nitrate and perchlorate ions in aqueous solutions under standard conditions have been generalized. Hydration numbers, interparticle distances, and ionic association types have been discussed and compared. The major difference between the ions is that nitrate ion tends to form ion pairs, whereas perchlorate ion does not.
TL;DR: The main substrates in wood biomass are cellulose and partly lignin this article, which is a large-scale waste product of microbiological industry and is a burdensome and environmentally harmful substance.
Abstract: Depletion of fossil organic raw materials has aroused the problem of switching to renewable resources. The key point in the development of technologies based on renewable sources is comprehensive utilization of renewable materials. Especially challenging is efficient involvement of wastes from processing of wood or other plant raw materials in production cycle. The main substrates in wood biomass are cellulose and partly lignin. Comprehensive utilization of plant raw materials, extension of product assortment, and minimization of wastes constitute the key problems in the development of wood processing enterprises and environmental safety. These problems may be solved via implementation of up-to-date chemical technologies and combination of works to achieve comprehensive utilization of wood. At first glance, wood resources on the Earth are huge. Forests occupy about 3.5 billion ha on the Earth surface, and wood resources amount to more than 350 billion m 3 . The annual wood increment is estimated at 5.5 billion m 3 , and the annual timber harvesting is more than 3 billion m 3 . However, taking into account high urbanization rates, reduction of forest fund, and insignificant net annual wood increment, extensive way of development of wood chemical industry seems inadmissible at present. The key product of the processing of carbohydratecontaining plant biomass is ethanol which is obtained by acid hydrolysis and is now actively offered as a promising substitute for traditional fuel. Wood conversion into ethanol, fodder yeast, and furfural in the presence of mineral acids (acid hydrolysis) is accompanied by formation of so-called “technical lignins” whose amount reaches many millions of tons per annum. Technical lignin is a large-scale waste product of microbiological industry and is a burdensome and environmentally harmful substance.
TL;DR: Platinum and palladium nanoparticles of 4-5 nm size applied at nanodiamonds have been shown to efficiently catalyze liquid-phase hydrogenation of different organic compounds (nitrocompounds, azomethines, and unsaturated hydrocarbons and alcohols) under mild conditions as discussed by the authors.
Abstract: Platinum and palladium nanoparticles of 4–5 nm size applied at nanodiamonds have been shown to efficiently catalyze liquid-phase hydrogenation of different organic compounds (nitrocompounds, azomethines, and unsaturated hydrocarbons and alcohols) under mild conditions (T = 318 K, hydrogen pressure of 0.1 MPa, solution in ethanol). Using of palladium on nanodiamond containing 3 wt % of metal has been most efficient.
TL;DR: In this article, a simple, facile, and efficient procedure for deoximation of oximes to the corresponding ketones and aldehydes with hexachlorodisilane (Si2Cl6) in the presence of SiO2 from good to high yields is described.
Abstract: A simple, facile, and efficient procedure for deoximation of oximes to the corresponding ketones and aldehydes with hexachlorodisilane (Si2Cl6) in the presence of SiO2 from good to high yields is described. Apparently, SiO2 greatly increases the reaction rate and product yield. The proposed procedure is more advantageous than those described previously due to its higher efficiency, milder reaction conditions, shorter reaction, and easier work-up.
TL;DR: In this paper, aqueous solutions of lead acetate and sodium sulfide in the presence of sodium ethylenediaminetetraacetate or citrate were prepared from microscopy and X-ray diffraction data, and the purity and size of the formed nanoparticles were determined by the reagents concentrations, presence and nature of the complexing ligand.
Abstract: Lead sulfide nanopowders have been prepared from aqueous solutions of lead acetate and sodium sulfide in the presence of sodium ethylenediaminetetraacetate or citrate. From microscopy and X-ray diffraction data purity and size of the formed nanoparticles are determined by the reagents concentrations, presence and nature of the complexing ligand, and the ratio of lead ions concentration to that of the ligand. PbS nanoparticles of the predefined size ranged from 5 to 55 nm can be prepared by controlled hydrochemical precipitation.
TL;DR: In this paper, the authors analyzed the performance of aniline hydrochloride in aqueous media under the assumption of formation of a charge-transfer complex between anilines and quinonediimine fragments of n-mers, and the total reaction rate order of the catalytic stage can be between unity and two.
Abstract: Kinetic features of oxidative polymerization of aniline hydrochloride in aqueous media have been analyzed under the assumption of formation of a charge-transfer complex between aniline and quinonediimine fragments of aniline n-mers. The total reaction rate order of the catalytic stage can be between unity and two. The reaction rate order of the catalytic stage in the presence of polyvinyl alcohol is changed from unity to two at heating. Rate constants of the single-electron transfer and the complex formation are independent of the concentration and molecular mass of polyvinyl alcohol.
TL;DR: In this article, the chemical stability of alkoxy-NNO-azoxymethane compounds to reduction with hydrazine hydrate has been studied and several reaction mechanisms have been proposed on the basis of the substrate reactivity toward nucleophiles, acids, and alkalies.
Abstract: The chemical stability of alkoxy-NNO-azoxy compounds to reduction with hydrazine hydrate has been studied. Methoxy-NNO-azoxymethane and bis(methyl-ONN-azoxy) formaldehyde acetal are more stable by orders of magnitude than bis(methoxy-NNO-azoxy)methane and 2,2-bis(methoxy-NNO-azoxy)propane. Methoxy-NNO-azoxymethane is also resistant to reduction with titanium(III) under acidic conditions and with iron(II) under basic conditions. Probable reaction mechanisms have been proposed on the basis of the substrate reactivity toward nucleophiles, acids, and alkalies.
TL;DR: In this paper, an efficient synthesis of 4′-[3-methyl-5-thioxo]-1H-1,2,4-triazol-4(5H)-yl]-2′,5′-diphenyl-2.4.dihydro spiro(indolin)-2-one derivatives using triethylamine in MeCN at room temperature is reported.
Abstract: In this paper 1,3-dipolar cycloaddition reaction has been studied. An efficient synthesis of 4′-[3-methyl-5-thioxo-1H-1,2,4-triazol-4(5H)-yl]-2′,5′-diphenyl-2′,4′-dihydro spiro(indolin-3,3′[1,2,4]triazol)-2-one derivatives using triethylamine in MeCN at room temperature is reported. The structures of the obtained compounds were confirmed by means of elemental analysis, MS and spectral (IR, 1H, and 13C NMR) methods.
TL;DR: In this article, specific features of formyl and acetylferrocene oxidation with peroxides ROOR (R = H, tert-C4H9) in different solvents are studied.
Abstract: Specific features of formyl- and acetylferrocene oxidation with peroxides ROOR (R = H, tert-C4H9) in different solvents are studied. It is shown that despite of the presence in complexes of strong electronacceptor substituents they can be oxidized with hydrogen peroxide in the absence of strong Bronsted acids. Dilution of water with organic solvent leads to deceleration and complete standstill of the reaction. In the absence of acids the second order of the process with respect to peroxide and first one with respect to the metal complex was evaluated. In the presence of perchloric or trifluoroacetic acid the order with respect to peroxide decreases to the first one. The dependence of the reaction rate on the concentration of acid has an extremum point. The activity of other peroxides in the reaction with the above-mentioned compounds is significantly lower than the activity of hydrogen peroxide. Probable alternative mechanisms of oxidation of the abovementioned ferrocenes with hydrogen peroxide in the presence and in the absence of acids differing in the way of coordination of reagents with one another and considering direct participation of substituent in the oxidation is suggested.