Nitrogen compounds heterogeneous hydrogenation

Hydrogen reduction of organic nitrogen compounds occurs readily in the presence of homogeneous and heterogeneous catalysts, " , e.g., nitro, nitroso, oxime, nitrile, imine, hydrazone and azide compounds are reduced ... 

The role of dissolved non-metals in the compatibility between liquid alkali metals and solid materials based on transition metals can be understood as a complicated system of local heterogeneous chemical equilibria. The chemical potentials of the non-metals such as oxygen, nitrogen, carbon, or hydrogen, are influenced by the formation of compounds. These compounds can be dissolved or precipitated. Several... 

As in the case of homogeneous catalysis, poisons can also lead to deactivation of heterogeneous catalysts. Soluble or volatile metal or nitrogen compounds can destroy acid sites, while carbon monoxide and sulphur compounds almost invariably poison nickel and noble metal hydrogenation catalysts by bonding strongly with surface metal atoms. These considerations often lead to the selection of less active, but more poison-resistant, catalysts for industrial use. 

In heterogeneous catalysis, the catalyst provides a surface on which the reactants are adsorbed. The chemical bonds of the reactants become weakened on the catalytic surface and new compounds ate formed. These compounds (products) have weaker bonds with the catalyst and consequently are released. An example of heterogeneous catalysis is the industrial synthesis of ammonia, which requires solid catalysts to obtain significant rates of reaction between nitrogen and hydrogen ... 

Heterogeneous catalytic hydrogenation of a carbon-nitrogen double bond over a metal catalyst in the presence of a chiral compound was first carried out by Nakamura. Acetophenone oxime was hydrogenated over platinum black with ethyl menthoxyacetate or tartaric acid to give a-methylbenzylamine with 15-18% ee. 

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