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The hydrogenation of a number of carbonyl compounds with the formation of the corresponding alcohols was studied. The process was carried out in a flow-type reactor in the presence of nickel catalysts supported on γ-Al2O3 obtained by the deposition-precipitation method with chemical reduction of the active phase. The effect of the catalyst preparation method on the yield of the resulting alcohols was studied. It has been shown that the increase in the nickel content in the catalyst leads to complete substrates conversion even at 20–80°C and atmospheric hydrogen pressure. [ABSTRACT FROM AUTHOR]

Properties of fractal speckle-like images used in art therapy and ophthalmology are considered. A traditional approach based on using two-dimensional fractal functions and a new technique based on representations of dynamic chaos are used to construct them. The important role of the scaling characteristics of Fourier transforms of fractal light structures is revealed. [ABSTRACT FROM AUTHOR]

Amines alkylation with alcohols catalyzed by γ-Al2O3-supported nickel and copper nanoparticles under continuous process conditions at atmospheric hydrogen pressure and 180–220°С has led to the formation of alkylated products with selectivity up to 100%. [ABSTRACT FROM AUTHOR]

A promising strategy in the synthesis of functional compounds with a cage structure is the use of 1,3-dehydroadamantane (tetracyclo[3.3.1.1.3,7.0.1,3]decane; 1,3-DHA; bridging [3.3.1]propellane) and its derivatives that are capable of restoring the adamantane structure in their reactions. The review provides information on the methods for the synthesis of 1,3-DHA, spectral characteristics, probable intermediates generated from propellanes, and the advantages of their using: low-stage syntheses of difficult-to synthesize adamantane derivatives, atomic precision, and "green chemistry." The reactions of 1,3-DHA with a wide range of organic compounds are considered, and its reactivity with respect to CH-, NH-, OH-, and SH-acids, as well as arenes, hydantoins, and heterocyclic compounds, is compared. New chemo- and regioselective methods for the one-step introduction of a 1-adamantyl group into the molecules of various substrates are classified. Particular attention is paid to the reactions of 1,3-DHA with various C–H acids, which enable the easy formation of C–CAd bonds to give hard-to-synthesize adamantane derivatives. The influence of pKa of the substrate on the selectivity of the reactions is demonstrated. Low-step methods for the synthesis of new adamantane derivatives, which have shown high activity as hsEH epoxide hydrolase inhibitors and antitumor agents, are described. [ABSTRACT FROM AUTHOR]

A one-step synthesis of hard-to-reach adamantyl polyfluoroalkyl ethers in yields up to 95% comprises the reaction of strained 1,3-dehydroadamantane with polyfluorinated alcohols. In the competitive reactions of 1,3-dehydroadamantane with pentan-1-ol and its fluorinated analog, the latter compound is etherified predominantly (∼3:5). [ABSTRACT FROM AUTHOR]

Using a modified deposition-precipitation method followed by sodium borohydride reduction of the precursor deposited on γ-Al2O3, copper-containing catalysts were obtained, which allow the continuous process of reductive alkylation of nitroarenes with alkanols at 200–220°C and atmospheric pressure of hydrogen with mono-N-alkylated products selectivity up to 100% and complete conversion of nitroarenes. [ABSTRACT FROM AUTHOR]

A procedure has been developed for the synthesis of rac-1-[isocyanato(phenyl)methyl]adamantane from rac-2-(adamantan-1-yl)-2-phenylacetic acid in 95% yield. The reactions of rac-1-[isocyanato(phenyl)-methyl]adamantane with aliphatic diamines and trans-4-[(4-aminocyclohexyl)oxy]benzoic acid afforded a series of N,N′-disubstituted ureas in 60–91% yields, and its hydrolysis in the presence of a catalytic amount of 1,8-diazabicyclo[5.4.0]undec-7-ene gave 94% of symmetrical N,N′-bis[(adamantan-1-yl)(phenyl)methyl]urea. The structure of rac-2-(adamantan-1-yl)-2-phenylacetic acid was confirmed by X-ray analysis of its single crystal. [ABSTRACT FROM AUTHOR]

Hydrogenation of 1,5,9-cyclododecatriene in the presence of nanostructured nickel catalysts in a flow-through reactor at atmospheric hydrogen pressure was studied. NaX zeolite was used as a support. Nickel nanoparticles on the support surface were prepared by chemical reduction of the precursor (NiCl2) with NaBH4 and NH2NH2. The influence exerted on the yield of hydrogenation products by the nominal residence time of the gas phase in the reaction zone and by the process temperature was considered, and the catalyst operation life was analyzed. The catalysts showed high activity and allowed preparation of cyclododecane in ~100% yield at a process temperature of up to 160°С. [ABSTRACT FROM AUTHOR]

The processes of hydrogenation of furan and its derivatives (2-methylfuran, furfuryl alcohol, and furfural) in plug-flow type reactor under atmospheric hydrogen pressure at 20–220°С in the presence of supported nickel nanoparticles prepared via chemical reduction have been investigated. It has been found that nickel nanoparticles supported on magnesium oxide surface are the most reactive and stable under the considered conditions. This catalyst allows the corresponding hydrogenation products with 100% yield and complete conversion of the substrate. [ABSTRACT FROM AUTHOR]

The reaction of 1,3-dehydroadamantane with alkylbenzenes was studied for the first time. It involved the C–H bond of the alkyl substituent in the α-position with respect to the aromatic ring. The proposed radical mechanism of the reaction was confirmed by the isolation of 1,1′-biadamantane and 1,2-diphenylethane derivatives. Difficultly accessible (adamantan-1-ylmethyl)arenes were synthesized in 53–78% yields. [ABSTRACT FROM AUTHOR]

Reductive amination of aldehydes and ketones with primary and secondary amines under catalysis with nickel nanoparticles supported on zeolite X, MgO, or activated carbon in the gas phase or in the gas-liquid system in a plug-flow reactor proceeds at atmospheric pressure of hydrogen with the formation of secondary or tertiary amines in high yield. [ABSTRACT FROM AUTHOR]

The processes of unsaturated cyclic hydrocarbons hydrogenation in a three-phase gas-liquid-solid catalyst system in the presence of nanostructured nickel, cobalt, or iron catalysts in a flow reactor at 130°C and atmospheric pressure have studied. RX3Extra activated carbon, γ-Al2O3, NaX zeolite, and Purolite CT-175 cation-exchange resin have been used as supports; NaBH4 and NH2NH2·H2O were used as reducing agents. The catalytic activity of supported nanoparticles and their selectivity with respect to the product of exhaustive hydrogenation have been investigated. [ABSTRACT FROM AUTHOR]

It has been found that nickel nanoparticles on NaX zeolite, γ-alumina, activated carbon, or magnesium oxide support catalyze the reduction of nitrobenzene and its homologs affording aniline and its derivatives in high yield. The effect of the substrate on the process in a continuous reactor at atmospheric hydrogen pressure has been investigated. The use of activated carbon or magnesium oxide as a carrier allows proceeding of the reaction at 80–100°C. [ABSTRACT FROM AUTHOR]

The reaction of 1,3-dehydroadamantane with aliphatic aldehydes involves the Ca-H bond and forms hardly accessible branched 2-(1-adamantyl)alkylaldehydes in one stage in a yield of 60-78%. It is found that 2-(1-adamantyl)alkylaldehydes are prone to oligomerization. The reaction of 2-(1-adamantyl)-alkylaldehydes with 2,4-dinitrophenylhydrazine gave the corresponding hydrazones in a yield of 84-98%. [ABSTRACT FROM AUTHOR]

The reaction of 1,3-dehydroadamantane with C2-C6 α,ω-alkanediols selectively afforded ω-(adamantan- 1-yloxy)alkan-1-ols in 87-94% yield. The reaction of 1,3-dehydroadamantane with ω-aminoalkan-1- ols (2-aminoethanol and 3-aminopropan-1-ol) gave mixtures of addition products through the oxygen and nitrogen atoms, which can be readily separated by fractional vacuum distillation or crystallization. [ABSTRACT FROM AUTHOR]

Nickel nanoparticles on the BAU-A active carbon or NaX zeolite catalyze hydrogenation of imines and enamines in a flow reactor in a gas phase or in a gas-liquid-solid catalyst system. The process occurs at atmospheric pressure of hydrogen and gives secondary or tertiary amines in a high yield. [ABSTRACT FROM AUTHOR]

The process of dicyclopentadiene hydrogenation in the gas-liquid-solid catalyst system with a catalyst of nickel nanoparticles supported onto a Purolite CT-175 cation exchange resin was studied. The surface structure of the catalyst and the kinetics of the dicyclopentadiene hydrogenation process were examined. Optimum conditions were found for the production of endo-tetrahydrodicyclopentadiene and the simultaneous production of endo-tetrahydrodicyclopentadiene and 5,6-dihydrodicyclopentadiene at atmospheric pressure. [ABSTRACT FROM AUTHOR]

1,3-Dehydroadamantane reacted with saturated carboxylic acid chlorides to give the corresponding 1-acyl-3-chloroadmantanes as the major products. In some cases, minor products of insertion into the Cα-H bond of acyl chloride were formed. The reactions of 1,3-dehydroadamantane with aromatic (heteroaromatic) carboxylic acid chlorides selectively afforded aryl (hetaryl) 3-chloroadamantan-1-yl ketones. The described reactions provide a synthetic route to difficultly accessible alkyl (aryl) ketones containing a 3-chloroadamantan- 1-yl group in one step under mild conditions with high yields. [ABSTRACT FROM AUTHOR]

Gas-phase hydrogenation of cycloalkenes in the presence of nickel nanoparticles supported on Ceokar-2, BAU-A activated carbon, alumina, and NaX zeolite proceeds at 140-240°C and atmospheric pressure of hydrogen. The conversion and selectivity depend on the type of support and on the hydrogen excess. [ABSTRACT FROM AUTHOR]

It has been stated that immobilized nickel nanoparticles catalyze disproportionation and cross-coupling of amines. The influence of the support on the catalysis of these properties in the in plug-flow reactor has been studied. The use of active carbon as the support has been found advantageous for the cross-coupling of amines, whereas alumina was a better support for the disproportionation reaction. [ABSTRACT FROM AUTHOR]

Reductive amination of carbonitriles catalyzed by nickel nanoparticles applied onto a solid support in a plug flow reactor in the gas phase or the gas-liquid-solid catalyst system occurs at atmospheric pressure of hydrogen affording the nonsymmetrical secondary or tertiary amines. The effect of the support type on the target product yield and conversion of the substrate has been studied. [ABSTRACT FROM AUTHOR]

Hydrogenation of aliphatic nitriles in the presence of nickel supported by NaX zeolite was studied. The data obtained were used to develop a continuous method for obtaining dialkylamines with the yield of the target product of up to 98%. [ABSTRACT FROM AUTHOR]

Conversion of the starting nitriles and selectivity of the products formation during continuous hydrogenation of various nitriles catalyzed by Ni/Ceokar-2 have been studied as functions of temperature. Performing the process at temperature 120-260°С has led to the formation of a mixture of products containing di- and trialkylamines as well as the corresponding imines and enamines. [ABSTRACT FROM AUTHOR]

Reaction of 1,3-dehydroadamantane with ethyl esters of α-halocarboxylic acids occurs either at C-H bond, or at C-Hlg bond. The regioselectivity of the reaction depends on the nature of the halogen. The ability of 1,3-dehydroadamantane to react at the C-Hlg grows in the series C-F < C-Cl < C-Br, which correlates with the energies of C-Hlg bonds. Difficultly available 1-R-3-halogen-substituted derivatives of adamantane were prepared under mild conditions in high yields. [ABSTRACT FROM AUTHOR]

Gas-phase hydrogenation of alkenes and their derivatives, catalyzed by nickel nanoparticles supported on zeolite or silica gel support occurs at 150-250°С and an atmospheric hydrogen pressure and results in a high conversion. The selectivity of the hydrogenation depends on the amount of hydrogen: at a low diene (triene)-hydrogen ratio, selective hydrogenation of one multiple bond in the substrate is possible. [ABSTRACT FROM AUTHOR]

Hydrogenation of carbonitriles catalyzed by nickel nanoparticles in the presence of primary amines led to the predominant formation of unsymmetrical secondary amines. In the presence of secondary amines hydrogenation of nitrites provided enamines as main products. Hydrogenation of nitriles in the presence of formamide or acetamide afforded formyl or acetyl derivatives of primary amines. [ABSTRACT FROM AUTHOR]

Nickel nanoparticles have been shown to be an accessible catalyst which allows hydrogenation of unsaturated compounds to be accomplished under atmospheric pressure of hydrogen at relatively low temperatures. Linear and cyclic alkenes, styrene and norbornene derivatives, as well as pinenes and camphene have been smoothly hydrogenated under these conditions. In some cases, selective hydrogenation of unsaturated carbon-carbon bond is possible with the other functional group remaining intact. [ABSTRACT FROM AUTHOR]

Hydrogenation of carbonitriles catalyzed by nickel nanoparticles in isopropanol proceeds under atmospheric pressure of hydrogen within 6-15 h to yield mainly secondary amines. Hydrogenation of α-aminonitriles results in reductive decyanation. β-Aminonitriles undergo hydrogenolysis at the nitrogen-carbon bond. [ABSTRACT FROM AUTHOR]

The reaction of carboxylic acids with ethylenediamine catalyzed by copper or iron oxide nanoparticles proceeds at 80°C with azeotropic water distilling off during 2-8 h to form 2- R-2-imidazolines. Acyl and diacyl derivatives of ethylenediamine are formed in the reaction as side products. [ABSTRACT FROM AUTHOR]

It was found that in the presence of colloid copper the direct amidation of some carboxylic acids with primary and secondary amines in benzene with azeotropic distillation of water became possible. The catalyst was proven to be suitable also for transamidation reaction of a number of carboxylic acid amides under mild conditions in solvent-free conditions. [ABSTRACT FROM AUTHOR]

Adamantylation of esters of dicarboxylic acids with 1,3-dehydroadamantane under mild conditions afforded in high yields diesters of (adamantan-1-yl)-substituted unsymmetrical dicarboxylic acids. [ABSTRACT FROM AUTHOR]

Alkylation of N,N-dialkylcarboxamides with 1,3-dehydroadamantane has been accomplished for the first time. The reaction involves the C-H bond in the α-position with respect to the carbonyl group and provides a convenient one-step preparation of substituted carboxylic acid amides containing an 1-adamantyl substituent and a pharmacophoric group in the amide moiety. [ABSTRACT FROM AUTHOR]

Modification of Leucart-Wallach reaction using catalytic amounts of copper colloid particles was developed. Reductive amination of a series of cyclic ketones proceeds at 100°C under a small excess of formamide or of alkyl(aryl)ammonium formate. [ABSTRACT FROM AUTHOR]

Aldehydes and ketones are found to be hydrogenated to alcohols with hydrogen at atmospheric pressure under the catalysis with nickel nanoparticles. The reaction under study may be used as technologically available and cheap method for hydrogenation of carbonyl groups. It is found that in the case of aromatic ketones hydrogenolysis of C=O bond with partial hydrogenation of aromatic groups takes place. [ABSTRACT FROM AUTHOR]

1,3-Dehydroadamantane and its methyl-substituted homologs react with carbonitriles at the α-carbon atom of the latter to give the corresponding α-adamantyl carbonitriles. This reaction provide a convenient one-step procedure for selective synthesis of branched nitriles which are difficult to obtain by traditional procedures. [ABSTRACT FROM AUTHOR]

Reaction of copper, nickel, and iron nanoparticles with β-diketones directly yields corresponding metal β-diketonates. Reaction of alkyl halides, β-diketones, and nanodispersed metals leads to a mixture of monoketone and the alkylated β-diketone. When alcohol is used as the alkylating agent instead of alkyl halide, corresponding ester is formed. [ABSTRACT FROM AUTHOR]

Reduction of a series of nitroarenes with hydrazine hydrate catalyzed with colloid iron, cobalt, nickel, and copper particles has been studied. High catalytic activity of nickel and iron nanoparticles has been demonstrated. Special features of nitrobenzene reduction in the presence of cobalt particles have been revealed. [ABSTRACT FROM AUTHOR]

Alkylation of primary amines with primary alcohols has been performed under catalysis by colloidal nickel and cobalt particles. The synthesis of the catalyst and alkylation of amines have been carried out in a one-pot mode. The alkylation at 160-180°C in 6-12 h yields 55-90% of secondary amines. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Results of investigation of selective hydrogenation of unsaturated carbon-carbon bonds with hydrazine hydrate or complex metal hydrides in the presence of metal nanoparticles are reported. Conditions of exhaustive and partial hydrogenation of some derivatives of norbornene, styrene, and unsaturated carboxylic acids are developed. [ABSTRACT FROM AUTHOR]

α-Amino nitriles containing a primary amino group undergo transamination with aliphatic and aromatic amines under mild conditions with high yields. A probable reaction mechanism involving intermediate elimination of cyanide ion has been proposed. [ABSTRACT FROM AUTHOR]

Reactions of 2-adamantan-2-one, acetone cyanohydrin, and amine lead to the formation of substituted 2-amino-2-cyanoadamantanes. The reaction is of a general character as has been proved by examples on a series of ketones and amines and it proceeds through the formation from the acetone cyanohydrin and amines of 2-amino-2-cyanopropane derivatives reacting further with the carbonyl compounds. [ABSTRACT FROM AUTHOR]

A mathematical model is developed for the thermal state of a graphitized electrode in an arc furnace with allowance for the Joule heat release, the arc and electrode radiation, free convection, and evaporation water cooling. A computer program is created, and the thermal state of the graphitized electrode is studied numerically. [ABSTRACT FROM AUTHOR]

A convenient method was developed for the preparation of potentially bioactive substances with 2-adamantyl radical and of intermediates for their synthesis. Condensation of adamantanone with methylene-active compounds was performed, and the reaction features were determined. [ABSTRACT FROM AUTHOR]

Synthetic routes to new amino nitriles with the functional groups at the 2-position of the adamantane core, based on reactions of adamantanonimines with acetone cyanohydrin or of adamantanone cyanohydrin with aliphatic amines, are considered. The products can be used for preparing new biologically active substances, unsymmetrical adamantyl-containing diamines or amino acids. [ABSTRACT FROM AUTHOR]

Adamantylation of carboxylic acids esters was performed with 1,3-dehydroadamantane for the first time. The reaction proceeds under mild conditions and can be used as a convenient single stage procedure for the synthesis of esters of branched carboxylic acids having an adamantyl group in the α-position to the carbonyl group. [ABSTRACT FROM AUTHOR]

The reaction of alkynes with hydrogen under atmospheric pressure in the presence of nickel nanoparticles as a catalyst led to the exhaustive hydrogenation of the triple bond. [ABSTRACT FROM AUTHOR]

This paper considers various experimental designs on the Atlas facility to study the physics of liners and determine the optimum conditions of their stable motion. In one of the versions, in comparison with the Liner Demonstration series of experiments, in which unstable liner motion was observed, it is proposed to reduce the initial liner radius without changing its mass, which, according to two-dimensional calculations, should to lead to more stable motion of the liner with unchanged velocity. It is also proposed to perform an experiment in which periodic perturbations at a certain wavelength are created on the outer surface of the liner with a simultaneous increase in its thickness. According to calculations, the growth of chaotic perturbations is stabilized in this case with the preservation of the liner velocity. [ABSTRACT FROM AUTHOR]

A method is described for choosing experimental parameters in studies of high-energy-density (HED) physics relevant to fusion energy, as well as other applications. An important HED issue for magneto-inertial fusion (MIF) is the interaction of metal pusher materials with megagauss (MG) magnetic fields during liner compression of magnetic flux and fusion fuel. The experimental approach described here is to study a stationary conductor when a pulsed current generates MG fields at the surface, instead of studying the inner surface of a moving liner. This places less demand upon the pulsed power system, and significantly improves diagnostic access. Thus the deceptively simple geometry chosen for this work is that of a z pinch composed of a metal cylinder carrying large current. Consideration of well known stability issues for the z pinch shows that for given peak current and rise time from a particular power supply, there is a minimum radius and thus maximum B field that can be created without disruption of the conductor before peak current. The reasons are reviewed why MG levels of magnetic field, as required for MIF, result in high temperatures and plasma formation at the surface of the metal in response to Ohmic heating. The distinction is noted between the liner regime obtained with cylindrical rods, which have a skin depth small compared to the conductor radius, and the exploding thin-wire regime, which has skin depth larger than the wire radius. A means of diagnostic development is described using a small facility (DPM15) built at the University of Nevada, Reno. It is argued that surface plasma temperature measurements in the 10-eV range are feasible based on the intensity of visible light emission. [ABSTRACT FROM AUTHOR]