<p>Ethyl 3-piperidine-carboxylate is an important intermediate in the pharmaceutical field. To break through the limitations of poor mechanical strength and thermal stability of catalysts and low catalytic efficiency of foam ceramic carriers due to the lack of active sites in traditional synthesis, this study used the hydrogenation synthesis of ethyl nicotinate to produce this intermediate as the probe reaction. Pd-Ni/Ru-Al<sub>2</sub>O<sub>3</sub>-SiO<sub>2</sub> foam ceramic catalysts were prepared by the sol-gel method and the impregnation method. Relying on the bimetallic differentiated synergistic effect of Ni, Ru, and Pd, the above technical bottlenecks were overcome. A variety of characterization techniques reveal its core mechanism of action: Pd serves as the catalytic core, and Ni can optimize the electronic structure, enabling the Pd-Ni alloy to obtain the optimal d-band center and adsorption energy, laying an electronic foundation for efficient catalysis. Ru can precisely control the particle size of Pd-Ru alloy, which is 4.5&#xa0;nm smaller than that of single-metal Pd, significantly improving the metal dispersion and the utilization rate of active sites. The three-dimensional network structure of foam ceramics enhances mass transfer efficiency. The γ-Al<sub>2</sub>O<sub>3</sub>-SiO<sub>2</sub> coating provides abundant active sites and excellent stability. The catalytic performance of this system has been significantly enhanced. Among them, the yield of the corresponding product of the Pd-Ni bimetallic catalyst reached 92.57%, and it still remained above 80% after five cycles of use, providing new prospects for the green and efficient synthesis of ethyl 3-piperidine-carboxylic acid esters and the development of low-cost hydrogenation catalysts.</p> Graphical Abstract <p></p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Pd-Ni/Ru-Al2O3 -SiO2 Coating Supports the Efficient Synthesis of Ethyl 3-Piperidine-Carboxylate on Foam Ceramics

  • Guopu Shi,
  • Fangxu Shi,
  • Fuxin Liang,
  • Yulin Wei,
  • Yuanguang Li,
  • Yubing Han,
  • Junyan Wu,
  • Sai Huang,
  • Honglei Wang,
  • Jun Ji,
  • Chao Wu

摘要

Ethyl 3-piperidine-carboxylate is an important intermediate in the pharmaceutical field. To break through the limitations of poor mechanical strength and thermal stability of catalysts and low catalytic efficiency of foam ceramic carriers due to the lack of active sites in traditional synthesis, this study used the hydrogenation synthesis of ethyl nicotinate to produce this intermediate as the probe reaction. Pd-Ni/Ru-Al2O3-SiO2 foam ceramic catalysts were prepared by the sol-gel method and the impregnation method. Relying on the bimetallic differentiated synergistic effect of Ni, Ru, and Pd, the above technical bottlenecks were overcome. A variety of characterization techniques reveal its core mechanism of action: Pd serves as the catalytic core, and Ni can optimize the electronic structure, enabling the Pd-Ni alloy to obtain the optimal d-band center and adsorption energy, laying an electronic foundation for efficient catalysis. Ru can precisely control the particle size of Pd-Ru alloy, which is 4.5 nm smaller than that of single-metal Pd, significantly improving the metal dispersion and the utilization rate of active sites. The three-dimensional network structure of foam ceramics enhances mass transfer efficiency. The γ-Al2O3-SiO2 coating provides abundant active sites and excellent stability. The catalytic performance of this system has been significantly enhanced. Among them, the yield of the corresponding product of the Pd-Ni bimetallic catalyst reached 92.57%, and it still remained above 80% after five cycles of use, providing new prospects for the green and efficient synthesis of ethyl 3-piperidine-carboxylic acid esters and the development of low-cost hydrogenation catalysts.

Graphical Abstract