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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]

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]

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 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]

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]

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]

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]

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]

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]

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]

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]

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]

Hydrogenation of enamines with hydrogen at atmospheric pressure was performed using nickel nanoparticles as a catalyst. The reaction may be used to produce tertiary amines under mild conditions using an accessible catalyst. [ABSTRACT FROM AUTHOR]

Hydrogenation of azomethines with hydrogen at atmospheric pressure using nickel nanoparticles as catalyst was carried out. Reaction may be used for the preparation of secondary amines under mild conditions on an available catalyst. Continuation of studies will lead to development of a convenient method for the reductive amination of carbonyl compounds. [ABSTRACT FROM AUTHOR]

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]

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 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]

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]