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The main work of this paper : in situ modification prepared tartaric acid modified Raney nickel catalyst system and its use in catalytic asymmetric hydrogenation of methyl acetoacetate . More systematic study of various factors such as : the amount of the reaction temperature and reaction pressure, type of solvent , tartaric acid , and additives ( such as sodium bromide , sodium acetate) , and the reaction time, etc. , the impact on the optical yield of the product , and hydrogenation activity ; analysis of the possible reasons for the results achieved . In addition, we also use different methods to different models of Raney nickel was prepared , and the system for catalytic asymmetric hydrogenation reaction . Also adopted a number of physical and chemical characterization methods , such as temperature-programmed desorption , infrared spectroscopy , x -ray diffraction , ion chromatography , ICP elemental analysis , scanning electron microscopy , nitrogen adsorption specific surface area of ??the catalytic system monitoring and research , in order to have a deeper understanding of the various factors affecting the substance . Inspection while also on the preparation conditions of the catalyst system and a catalytic reaction conditions were optimized, under optimized conditions , i.e. , using methanol as the reaction solvent , added in an amount of tartaric acid and sodium bromide , respectively 50mg, 15mg , using the modified of T-1 type Raney nickel as the active ingredient, 0.05mL of acetic acid was added dropwise , and the reaction hydrogen pressure is 6Mpa, the reaction temperature was 60 ° C , to obtain a maximum optical yield of 61.6% , which is also reported in the literature to date Raney nickel as the active ingredient in the in situ method of modifying obtain the best results .
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