| The hydrogenation of quinoline and its derivatives is of high industrial relevance, with applications in the petrochemical, fine chemical and pharmaceutical industries. The 8%Ru-ZrO2 nanocomposite catalyst was prepared by coprecipitation of ruthenium trichloride and zirconium oxychloride with ammonia, followed by hydrogen reduction in propanol.By use of transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), the catalyst was characterized. The zirconium dioxide supported ruthenium was reduced to low valence and the average partical diameter of Ru crystallites was 10nm. The hydrogenation parameters: such as temperature, hydrogen pressure and the catalyst concentration on the reactivity were investigated. Under the mild reaction conditions: 80℃, 4.0 MPa, 2.5h, propanol as the solvent, the main product obtained was the partially hydrogenated 1,2,3,4- tetrahydroquinoline .When the pressure and temperature rise to 160℃, 6Mpa, quinoline could be fully hydrogenated to decahydroquinoline without fresh catalyst. The hydrogenation mechanism of quinoline was discussed.The asymmetric hydrogenation of prochiral ketones is one of the most efficient methods of producing enantiomerically enriched secondary alcohols. The ruthenium complex RuCl2[P(C6H5)3]2-(S,S)-DPEN(DPEN=1, 2-diphenylethylene-diamine) was applied to the asymmetric hydrogenation of benzalacetone. The effects of reaction temperature, hydrogen pressure, and molar ratio of base to catalyst on the activity and enantioselectivity were investigated in an isopropanol solution of KOH. The results showed that the increase in the temperature and pressure accelerated the reaction but slightly decreased the enantioselectivity for unsaturated alcohol. Under the optimum reaction conditions, :benzalacetone:Ru:KOH=1000:1:20 (molar ratio), 2 MPa, 30℃, and 2h, the conversion and the selectivity toward the unsaturated alcohol was reached 99% and 99%, respectively, and the ee value of unsaturated alcohol was over 58.9%.
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