New Method For Synthesis Research Articles

Growing of Carbon Nanotubes from Hydrocarbons in an Arc Plasma

A new method of synthesis of multilayer carbon nanotubes from liquid hydrocarbons is proposed. The interaction of an electric arc, fi ring between an anode and a cathode submerged in a thick layer of a heavy-hydrocarbon liquid, with hydrocarbon molecules was investigated for the purpose of obtaining new light fractions of oil and an atomic carbon. The carbonaceous substance deposited on the cathode was analyzed on an electron microscope. Chromatographic investigations of the products of the plasmachemical decomposition of heavy hydrocarbons have been performed. It was established that carbon nanotubes are present in a large amount in the deposit on the cathode and that the volatile oil fractions include gasoline fractions, acetylene, methane, ethane, and other substances.

Polymer with Intrinsic Microporosity PIM-1: New Methods of Synthesis and Gas Transport Properties

A ladder polymer with the intrinsic microporosity PIM-1 has been synthesized via precipitation polycondensation in dimethylsulfoxide and via polycondensation in N,N,N ',N '-tetramethylurea. The molecular weight characteristics of PIM-1 samples have been determined using gel permeation chromatography method. It has been shown that the synthesized polymers are characterized by a high molecular weight (~90 × 103) and by a bimodal molecular weight distribution; in this case, molecular weights of the high-molecular-weight fraction of polymer with the polydispersion coefficient of 2.1–2.4 are practically independent of the nature of the reaction medium. The weight content of the oligomer fraction in the obtained samples has been estimated from gel permeation chromatograms. Gas permeability coefficients of He, H2, O2, N2, CO2, and CH4 for the initial films of the synthesized polymers and the films treated with ethanol have been measured by the chromatographic method at 22 ± 2°С. It has been shown that, for all samples under investigation, the gas permeability coefficients are higher than for the PIM-1 samples described previously in the literature. In this case, the gas permeability and its increase during treatment with ethanol depend on the content of the low-molecular-weight fraction in the sample.

New method for synthesis of fine crystalline magnesium aluminate spinel

A new method for the synthesis of high-purity fine-crystalline aluminum-magnesium spinel MgAl2O4 was been proposed. The procedure includes treatment of mixture finely dispersed MgO and hydroxide Al(OH)3 or aluminum oxyhydroxide AlOOH by water fluid under supercritical conditions (T = 380-400 °С, PH2O = 22,8-23,0 MPa). It was been shown that the process of formation of the structure of aluminum-magnesium spinel proceeds through a solid-phase mechanism. By varying the conditions of synthesis, the new method of synthesis allows to adjust the size (from 20 nm to 5 µm) and shape (spherical, lamellar, bipyramidal) of particles of synthesized aluminum-magnesium spinel MgAl2O4.

Synthesis of Waterborne Polyurethanes Using the Isophorone Diisocyanate Oligoisocyanurates

The new method of synthesis of waterborne polyurethanes with isophoronediisocyanateoligoisocyanurates as the isocyanate containing compound was developed and approved.

A New Method for Synthesis of Fine Crystalline Magnesium Aluminate Spinel

A New Method for Synthesis of Fine Crystalline Magnesium Aluminate Spinel

A New Method for Synthesis of Binary Borides with Desired Properties

Complexes [Co(solv)n][B10H10], where (I: solv = H2O, n = 6; II: solv = N2H4, n = 3) have been synthesized and characterized. The possibility to use them as precursors in the synthesis of binary borides has been demonstrated. The purity and homogeneity of the precursors and the products of their thermal reduction (in an inert atmosphere at 650 and 900°С) has been established by elemental analysis, X-ray powder diffraction, and IR spectroscopy; magnetochemical studies of the precursors and their annealing products have been carried out. According to the data obtained, the reduction products are structured oxide-boride and nitride-boride phases, respectively. Magnetochemical study of the phases has revealed a significant difference in their magnetic behavior: the oxide-boride phase is characterized by a significant ferromagnetic contribution to the total magnetization of the sample, while the nitride-boride phase, by a diamagnetic contribution.

Reactivity study of a β-diketiminate titanium(III) complex with a phosphanylphosphido ligand towards chlorophosphanes. A new method of synthesis of β-diketiminate titanium(IV) complexes with versatile phosphanylphosphinidenes

The reactivity of a β-diketiminate titanium(III) complex with a phosphanylphosphido ligand, [MeNacNacTi(Cl){η2-P(SiMe3)-PtBu2}] (1) (MeNacNac− = [Ar]NC(Me)CHC(Me)N[Ar]; Ar = 2,6-iPr2Ph), was investigated towards selected chlorophosphanes, such as tBu2PCl, iPr2PCl, Cy2PCl, (Cy)tBuPCl, (Me)tBuPCl, (Ph)tBuPCl, Ph2PCl, (iPr2N)tBuPCl and (Et2N)2PCl. The reactions with tBu2PCl and Ph2PCl lead mainly to the earlier described complex [MeNacNacTi(Cl){η2-P-PtBu2}] (1a), while the reactions with iPr2PCl, Cy2PCl, (Cy)tBuPCl, (Me)tBuPCl and (Ph)tBuPCl lead to mixtures of different β-diketiminate titanium(IV) complexes with phosphanylphosphinidene ligands: 1a and [MeNacNacTi(Cl){η2-P-PiPr2}] (1b), 1a and [MeNacNacTi(Cl){η2-P-PCy2}] (1c), 1a and [MeNacNacTi(Cl){η2-P-P(Cy)tBu}] (1d), 1a and [MeNacNacTi(Cl){η2-P-P(Me)tBu}] (1e), 1a and [MeNacNacTi(Cl){η2-P-P(Ph)tBu}] (1f) respectively. The newly obtained compounds 1c and 1d were isolated and their identities unambiguously confirmed by X-ray diffraction, NMR spectroscopy and elemental analysis. In the reaction with (Et2N)2PCl the related titanium(IV) complex is not observed, but the phosphetane tBu2P-P(µ2-PNEt2)2P-PtBu2 (3) is formed.

Digital economy in assessing the investment attractiveness of innovative enterprises based on the results of their own scientific and technical research in the field of petrochemical chemistry

The concept of the digital economy greatly simplifies the solution of multi-criteria choice problems in an innovative environment, in particular, when an economic assessment of the investment attractiveness of a number of enterprise projects with a set of varied in a wide range of technical indicators and commercialization indicators is necessary. Based on the example of small innovative enterprises based on the results of their own scientific and technical research in the field of petrochemical chemistry, a model for the formation of investment portfolios is compiled, taking into account the impact of costs on an improved set of product technical characteristics and the relevance of the level of these characteristics by the investor. The choice of projects from the field of petrochemical chemistry is due to the high importance of this sector both in the economy of individual regions, as the most flexible and at the same time self-sufficient economic system, for example, the Republic of Tatarstan, and at the national and global level. The presence of own scientific developments of the co-author of the article in the field of petrochemical and chemical cluster provides a close relationship of the economic component of innovative projects with variation of all possible technical and technological characteristics of an innovative product in a wide range, depending on investors’ requirements. In addition to traditional applications, the complex of transparent high-strength polymers and polymers with non-stick properties, based on the principles and mechanisms of anionic (co) polymerization of cyclic carbonates with isocyanate-containing compounds under conditions of anionic initiation, gained interest in space technologies, technologies of nano-sized particles and liquid crystals, which requires the search for new methods of synthesis and digital on-line interrelation of the changing costs of the project with its economic efficiency.

Iron-Catalyzed Dihydrosilylation of Alkynes: Efficient Access to Geminal Bis(silanes).

Geminal bis(silanes) are versatile synthetic building blocks owing to their stability and propensity to undergo a variety of transformations. However, the scarcity of catalytic methods for their synthesis limits their structural diversity and thus their utility for further applications. Herein we report a new method for synthesis of geminal bis(silanes) by means of iron-catalyzed dihydrosilylation of alkynes. Iron catalysts were distinctly superior to the other tested catalysts, which clearly demonstrates that novel reactivity can be found by using iron catalysts. This method features 100% atom economy, regiospecificity, mild reaction conditions, and readily available starting materials. Using this method, we prepared a new type of geminal bis(silane) with secondary silane moieties, the Si-H bonds of which can easily undergo various transformations, facilitating the synthetic applications of these compounds. Preliminary mechanistic studies demonstrated that the reaction proceeds via two iron-catalyzed hydrosilylation reactions, the first generating β-( E)-vinylsilanes and the second producing geminal bis(silanes).

New method for synthesis of BaFe12O19/Sm2Ti2O7 and BaFe12O19/Sm2Ti2O7/Ag nano-hybrid and investigation of optical and photocatalytic properties

Nanoscale BaFe12O19/Sm2Ti2O7 and BaFe12O19/Sm2Ti2O7/Ag ternary nano-hybrid were successfully synthesized by a new method for the first time. PEG, PVA, and PVP were used to investigate their effects on the morphology and particle size of final products. The photocatalytic efficiency of BaFe12O19/Sm2Ti2O7/15%Ag was improved by 59% which was higher than pure BaFe12O19/Sm2Ti2O7 for the degradation of MB. In this work, Ag was doped with BaFe12O19/Sm2Ti2O7 with the aid of improving its photocatalytic activity and stability toward degradation of dyes under visible light irradiation. Transmission electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, Fourier transform infrared, photoluminescence, diffuse reflection spectroscopy, and Field emission scanning electron microscopy were applied to characterize BaFe12O19/Sm2Ti2O7/Ag ternary nano-hybrid.

Rapid reaction of Mo2N nanowires with Pb2+ ions in water and its use for production of PbMoO4 nanoparticles

Abstract Molybdenum nitrides, which are used as hard coatings or corrosion and abrasion resistant layers, are in general considered as having good chemical resistance. We find, however, that molybdenum nitride Mo2N nanowires promptly react with lead nitrate in water at room temperature, resulting in formation of lead molybdate nanoparticles. Depending on the initial concentrations, the resulting material are either hybrid nanowires decorated with individual lead molybdate nanoparticles, or solely lead molybdate nanoparticles. The synthesised nanoparticles are fairly uniform in size, with diameters of up to a hundred nanometres. We find that the particle size is practically independent of the initial concentrations that we used. The performed one-step reaction, which is almost immediate and requires no additional reagents, clearly shows chemical reactivity of molybdenum nitrides and opens a new use for molybdenum nitrides as starting materials in a variety of chemical reactions. At the same time, the demonstrated reaction presents a new method for synthesis of lead molybdate nanoparticles or hybrid materials using molybdenum nitride nanowires as the starting material.

A New Method of Synthesis of Nanosized Boehmite (AlOOH) Powders with a Low Impurity Content

A new method of synthesis of nanosized aluminum oxyhydroxide (AlOOH, boehmite) powders has been suggested through a hydrothermal treatment of nanosized γ-Al2O3 powder in water and a 1.5 wt % HCl solution at different temperatures. It has been found that hydrothermal treatment in a 1.5 wt % HCl solution leads to the purification of the starting material; different treatment durations allow one to obtain boehmite particles of different shape. It has been demonstrated that a nanosized boehmite powder is obtained upon the hydrothermal treatment of a nanosized γ-Al2O3 in water above 80°С. The nanosized boehmite powders synthesized at different temperatures have been studied by various methods.

New method of synthesis of hierarchical mordenite of high crystallinity and its application in hydroizomerization of benzene-n-heptane mixture

A new approach to the formation of hierarchical porous structure of mordenite without use of templates is suggested in the presented work. The method is based on the crystallization of mordenite in granules consisting of amorphous aluminosilicate (metakaolin), fumed silica and mordenite crystals, provided that the crystalline phase content must be higher than that of the amorphous phase. The synthesized material is characterized by high crystallinity (up to 92%) with the volume of micro-, meso- and macro-pores of 0.15, 0.20 and 0.18 cm3/g, respectively. The research results showed that MOR type zeolite with a hierarchical structure in the H-form has total acidity in ammonia of about 860 µmol/g and after promotion of 0.3% wt platinum exhibits high activity and selectivity in the hydroisomerization of a model mixture of benzene–heptane into methylcyclopentane and isomers of n-heptane.

Ultrafine powder of barium titanate for production of lead-free ceramic piezomaterials

The paper is aimed to perform and compare the capabilities of the solid state technology and a new method of synthesis in supercritical water for the production of barium titanate powder. This material is of interest for applications such as dense piezoceramics. The new method of synthesis in an aqueous medium allowed obtaining barium titanate of higher phase purity and with a narrow crystal size distribution compared to the solid state method. The ceramics manufactured from the barium titanate powder synthesized in supercritical water possessed a consistently high dielectric constant (2400-2600) and a low loss tangent (∼ 10−2) at low and medium frequencies.

New Method of Synthesis of Nano-Dimensional Bemit Powders (AlOOH) with Low Content of Impurities

New Method of Synthesis of Nano-Dimensional Bemit Powders (AlOOH) with Low Content of Impurities

Thermal decomposition study of nanostructured amorphous lithium, sodium and potassium metatitanates

A new method of synthesis of advanced hydrated metatitanate pseudomorphs obtained via extraction of sulfate ions from the crystals of titanyl sulfate dihydrate and their replacement with hydroxyl groups of NaOH, LiOH and KOH solutions leaving the Ti-O framework untouched has been proposed. The resulting materials exhibit specific structural properties, which were determined by a number of methods, including scanning and transmission electron microscopy, X-ray diffraction and thermal analysis coupled with mass spectrometry. It was observed that while material precipitated by KOH is thermally stable up to 150 °C, the decomposition of LiOH and NaOH materials starts right at the beginning of the heating. With the increasing temperature, the amorphous materials start to crystallize into various lithium, sodium and potassium titanates and furthermore the growth of larger crystals and nanowhiskers on rods during the crystallization process was observed and discussed.

New Method of Synthesis of Biologically Active Get(aryl)chalcogenylacetates of Tris(2-hydroxyethyl)ammonium

Physiologically and pharmacologically active het(aryl)chalcogenylacetates of tris(2-hydroxyethyl)ammonium of pharmacopeial purity have been synthesized by the reaction of het(aryl)chalcogenylacetic acids with sodium (potassium) hydroxide and triethanolamine hydrochloride by one-pot method in quantitative yield (up to 99.8%).

Oxidation of 4­brometylbenzene by ozone in acetic acid

The kinetics and the mechanism of ozonation of 4-bromethylbenzene in acetic acid was studied. The constants of the rate of reaction of ozone with 4-bromethylbenzene and 4-bromacetophenone at different temperatures were determined. We showed the possibility of conducting the process not only by the aromatic ring of the substrate in accordance with the Krige mechanism, but also with the formation of 4-bromacetophenone, which will be used when creating new methods of synthesis of oxygen-containing derivatives of ethylbenzene. It was established that oxidation of 4-bromethylbenzene by ozone in acetic acid flows mainly by the aromatic ring with the formation of ozonides – peroxide products of aliphatic nature. Up to 35 % of 4-bromacetophenone and trace amounts of 1-(4-bromphenyl)ethanol were identified among the products of oxidation reaction by the side chain. The reaction of ozone with 4-bromethylbenzene in acetic acid at temperatures of up to30 °Chas the first order by initial components and the value of constant of reaction rate does not depend on the concentration of reactants. With increasing temperature, constant of reaction rate begins to depend on the concentration of reagents, and in this case, ozone consumption increases significantly. This indicates that under experimental conditions, ozone is consumed simultaneously at different stages of oxidation. It was proved that ozonation of 4-bromethylbenzene is a complicated process, in which the substrate is oxidized by the non-chain mechanism. Ozone is consumed in two directions: in the reaction with the substrate by non-chain mechanism and by the chain mechanism at the stage of chain continuation in the reaction with the products of thermal decomposition of ozonides. This fact gives grounds to argue that at an increase in temperature, unproductive consumption of ozone will grow rapidly and, vice versa, under conditions of prevention of ozonolysis, ozone will participate in the reaction with formation of the target aromatic product. Thus, the experimentally obtained data are the basis for the development of the process of oxidation of derivatives of ethylbenzene and creation of the foundations of technology of 4-bromacetophenone synthesis with the help of ozone. This will considerably simplify the apparatus design of the process, enhance the output of the target product and will contribute to subsequent improvement of the method of oxidative processing of reagents

A New Method of Synthesis of Nanosized Metal Oxide Powders

A new method of synthesis of nanosized metal oxide powders (Al2O3, MgO, ZnO) has been suggested. The method involves successive heat treatment at 350°С and then at 800°С of saturated solutions of the corresponding metal salts and sucrose. Physicochemical and technological properties of the synthesized materials have been determined.

A More Sustainable Process for Preparation of the Muscarinic Acetylcholine Antagonist Umeclidinium Bromide.

A more sustainable process for the synthesis of the long-acting muscarinic acetylcholine antagonist umeclidinium bromide is described. Specifically, we report the synthesis of ethyl 1-(2-chloroethyl)-4-piperidinecarboxylate, a key intermediate in the preparation of umeclidinium bromide, in good yields using triethylamine, as well as the identification and characterization of the by-product formed in this reaction. This new method of synthesis leads to an improvement in yield over that of previously reported protocols using potassium carbonate as base (65.6 % versus 38.6 %). Moreover, in the final synthetic step of the process to obtain umeclidinium bromide, we were able to replace the use of toxic solvents (acetonitrile/chloroform) with water. The use of this green solvent allowed precipitation of the active pharmaceutical ingredient (API) from the reaction medium with high purity and in high yield. Overall, we have developed a more efficient and environmentally friendly process for the synthesis of the umeclidinium bromide API with a higher overall yield (37.8 % versus previously reported overall yield of 9.7 %).