Catalysts For Synthesis Of Pyridine Base

The compounds of the pyridine bases are a huge system,and the range of their applications has continually been expanding.Pyridine bases are raw materials in chemical industry,especially the fine chemical industry being involved in fragrances,pharmaceutical intermediates,pharmaceutical products,pesticides,pesticide intermediates,feed and feed ingredients and other fields.2,3-cyclopentenopyridine is a very useful pyridine base.It has physiological activity of the anti-ulcer,anti-cancer,and becomes the research focus of the antibiotics industry in many countries as the key intermediate for synthesis of the fourth-generation antibiotic Cefpirome.This research used the solid catalyst with multi-metal components for catalytic synthesis of 2,3-cyclopentenopyridine.The main contents are as follows.In the first part,the catalysts of Ti-V/γ-Al2O3 containing different amounts of V and Ti were prepared by impregnation.Acrolein,cyclopentanone and ammonia as raw materials were added in the gas-solid reactor to synthesis of 2,3-cyclopentenopyridine.The best catalyst 4%Ti-2%V/γ-Al2O3 with optimum content of titanium and vanadium was found via experiments.Then,the catalyst life test over the best catalyst was performed.In the second part,the optimum technology conditions to synthesis of 2,3-cyclopentenopyridine were investigated for the best catalyst with optimum metal content.The performance of catalyst was studied at different reaction temperature,reactant ratio and space velocity.Then,the life of the best catalyst was carried under the optimum process condition.The optimum conditions were that reaction temperature was 300℃ and the molar ratio of cyclopentanone and acrolein and ammonia was 1:1.75:4 and liquid hourly space velocity is 0.095h-1.Under these conditions,the catalyst of 4%Ti-2%V/－γ-Al2O3 afforded 98%conversion of acrolein with 82%selectivity of 2,3-cyclopentenopyridine in 4 hours reaction,The catalyst remained active after 43 hours reaction.The catalysts with high catalytic performance were characterized by powder X-ray diffraction(XRD),diffuse reflectance UV visible spectroscopies(UV-Vis),Fourier transform infrared spectroscopies(FT-IR),thermogravimetric,differential thermal analysis(TG-DTA)and NH3 temperature-programmed desorption(NH3-TPD)to investigate the change laws of the catalyst during the reaction process.