Hydrogenation Of Acetophenone On Chirally Modified Ruthenium Nanocatalysts

As one of the most important research topics in organic synthesis,the research on the catalytic hydrogenation of acetophenone has a great influence on the production of daily chemicals and pharmaceutical materials.In the process of chemical production,catalytic hydrogenation technology is beneficial to reduce the waste emissions and improve the product performance and production efficiency.In recent years,heterogeneous chiral hydrogenation has attracted much attention from academia to industry.In this thesis,a series of ruthenium catalysts were prepared for the hydrogenation of acetophenone,and the effect of supported carbon nanotubes on the performance of the catalyst and the effect of the supported ruthenium metal nanoparticles on the catalyst were investigated in detail.The main results of the thesis were as follows:1.Ruthenium nanometallic catalysts were prepared on the outer or inner surface of carbon nanotubes by using different types of carbon nanotubes as carriers.Chiral ligands such as(1S,2S)-DPEN,L-Proline,and R-BINAP were used to modify them in situ.The method of chiral ligands and the stabilization of TPP were carried out on the catalytic hydrogenation of acetophenone.In the prepared catalyst systems,acetophenone can be transformed completely,and the highest enantioselectivity of the product can reach 80.8%.A new preparation route for Ru@CNTs catalyst was explored,which shortened the preparation time of the catalyst and reduced the preparation process of the catalyst,so that the catalyst was exposed to air and was not easily oxidized.The effect of carbon nanotubes on the particle size of ruthenium nanoparticles supported on it was studied.The improvement direction of Ru@CNT type catalyst was obtained by analyzing the structure of the catalyst by means of TEM,XRD,XPS,BET,H2 Pulse Chemisorption characterization methods.The confinement effect of the carbon nanotubes on the nanoparticles loaded thereon was explored.2.The stability of the Ru/CNTs catalyst was enhanced by modifying the chiral ligand(1S,2S)-DPEN on the outside of the carbon nanotubes.At the same time,the structure of the catalyst was analyzed by characterization means of TEM,FT-IR,etc.,and the synergistic effect of chiral ligand(1S,2S)-DPEN and stabilizer TPP on the hydrogenation of acetophenone was also found by compared with the experimental results.3.The(1S,2S)-DPEN and R-BINAP synergistic catalytic systems and the L-proline-modified rhodium catalytic system were explored,which enriched the catalytic reaction system for the hydrogenation of acetophenone.