The Enantio-differentiating Hydrogenation Of Methyl Acetoacetate Over Tartaric Acid Modified Raney Nickel Catalysts With In-situ Modification

This thesis contains mainly the preparation of the tartaric acid modified Raney nickel catalyst with in-situ modification and its application in the asymmetric hydrogenation of methyl acetoacetate.The influence of most important factors on the optical yield and,in part,on the hydrogenation activity varying the reaction temperature and pressure,solvent type,the amount of tartaric acid,additive(NaBr,Na acetate) and the reaction time were systematically investigated.The possible cause has been given after the study.Various Raney nickel catalysts were used in this paper.Also, various physico-chemical methods,such as temperature-programmed desorption(TPD),infra-red spectroscopy(FTIR),X-ray diffractometry (XRD),ion chromatography(IC),inductive coupled high frequency plasma source(ICP),scanning electron microscopy(SEM),BET surface area,and so on,were employed to gain a deeper understanding of the inherent problem of the factors effect.The conditions of the catalyst preparation and reaction were improved at the same time.The highest optical yield of 61.6%was achieved over the improved T-1 RNi catalyst with an addition of 0.05 ml acetic acid under the optimal conditions(MeOH as solvent,50 mg TA,15 mg NaBr, 0.05 ml acetic acid,6 MPa H₂,60℃).Compared with previous literatures,this is the best result for the enantio-differentiating hydrogenation of methyl acetoacetate over the in-situ modified Raney nickel catalyst.