Yang Di, Li Weijie, Deng Xin, Chai Yuchao, Wu Guangjun, Li Landong
Key Laboratory of Advanced Energy Materials Chemistry of Ministry of Education, College of Chemistry, Nankai University, Tianjin, 300071, PR China.
Chem Asian J. 2024 Dec 2;19(23):e202400878. doi: 10.1002/asia.202400878. Epub 2024 Oct 18.
The selective hydrogenation of nitroaromatics plays an essential role in the chemical industry for the synthesis of anilines and their derivatives, which are known as crucial fine chemicals and pharmaceuticals. In this study, we demonstrate the preparation of Pd/Ti monolith catalyst containing well-isolated metallic Pd sites on Ti substrate through a simple impregnation method, showing remarkable catalytic properties in the selective hydrogenation of nitroaromatics containing various functional groups. Kinetic analyses reveal an apparent activation energy of 61 kJ/mol and the kinetic isotope effect (K/K) of ~1.7 in the hydrogenation of 3-chloronitrobenzene over Pd/Ti-200 ppm catalyst, indicating the facile dissociation of dihydrogen and the subsequent efficient hydrogenation. The Pd/Ti-200 ppm catalyst also demonstrates good stability and recyclability, maintaining its performance over multiple cycles. This simple but innovative approach not only enhances the efficiency of Pd catalysts in the selective hydrogenation of nitroaromatics but also offers significant potential for industrial applications in aniline production.
硝基芳烃的选择性加氢在化学工业中对于合成苯胺及其衍生物起着至关重要的作用，苯胺及其衍生物是重要的精细化学品和药物。在本研究中，我们展示了通过简单的浸渍法制备在钛基底上含有良好隔离的金属钯位点的钯/钛整体催化剂，该催化剂在含有各种官能团的硝基芳烃的选择性加氢中表现出显著的催化性能。动力学分析表明，在钯/钛-200 ppm催化剂上3-氯硝基苯加氢反应的表观活化能为61 kJ/mol，动力学同位素效应（K/K）约为1.7，这表明氢气易于解离并随后进行高效加氢。钯/钛-200 ppm催化剂还表现出良好的稳定性和可回收性，在多个循环中保持其性能。这种简单而创新的方法不仅提高了钯催化剂在硝基芳烃选择性加氢中的效率，而且在苯胺生产的工业应用中具有巨大潜力。
