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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]

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]

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]

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]

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]

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]

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]

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]

Abstract  The possibility of obtaining adamantyl-substituted phenols by the reaction of 1,3-dehydroadamantane with phenols in the presence of catalytic amounts of sulfuric acid was studied. [ABSTRACT FROM AUTHOR]

The article focuses on the synthesis of adamantyl-substituted keto esters. Reaction between 1,3-dehydroadamantane and a series of ketoesters, among which was cyclic methyl 2-oxocyclopentanonecarboxylate was performed. The adamantylation of ethyl acetoacetate in a boiling inert solvent, ethyl ether, under an atmosphere of dry nitrogen purified from oxygen at the molar ratio of reagents 1,3-dehydroadamantane and ethyl acetoacetate equal to 1: 1.5-2 within 1-2 hours afforded ethyl 2-(1-adamantyl)-3-oxobutanoate in a moderate yield.