College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, Henan Province, P. R. China.
Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P.R China.
Nanoscale. 2017 Jan 5;9(2):781-791. doi: 10.1039/c6nr07521e.
A novel "tunnel-like" cyclopalladated arylimine was prepared and immobilized on graphene oxide nano-sheet to form a hybrid catalytic material (denoted as F-GO-Pd) by self-assembly. The F-GO-Pd catalyst was characterized by XRD, FTIR, Raman, XPS, SEM, and TEM. This novel hybrid catalytic material was proven to be an efficient catalyst for the Suzuki-Miyaura coupling reaction of aryl halides (I, Br, Cl) with arylboronic acids in aqueous media under mild conditions with a very low amount of catalyst (0.01 mol%) and a high turnover frequency (TOF) (>20 000 h). In particular, high yields also could be obtained at room temperature with prolonged time. F-GO-Pd also showed good stability and recyclability seven times with a superior catalytic activity. The heterogeneous catalytic mechanism was investigated with kinetic studies, hot filtration tests, catalyst poisoning tests, and in situ FTIR spectroscopy with a ReactIR and the deactivation mechanism of the catalysts was proposed through analysis of its chemical stability by TEM, SEM, Raman, and XRD, indicating that a heterogeneous catalytic process occurred on the surface and the changes of the catalytic activity during the recycling were related to the micro-environment of the catalyst surface.
一种新型的“隧道状”环钯芳基亚胺通过自组装被固定在氧化石墨烯纳米片上，形成了一种混合催化材料（记为 F-GO-Pd）。F-GO-Pd 催化剂通过 XRD、FTIR、Raman、XPS、SEM 和 TEM 进行了表征。这种新型的混合催化材料被证明是一种高效的催化剂，可在温和条件下，在水相中催化芳基卤化物（I、Br、Cl）与芳基硼酸的 Suzuki-Miyaura 偶联反应，催化剂用量非常低（0.01mol%），周转频率（TOF）非常高（>20000 h）。特别是，在延长时间的情况下，室温下也能获得高产率。F-GO-Pd 还表现出良好的稳定性和可重复使用性，经过七次循环仍具有优异的催化活性。通过动力学研究、热过滤试验、催化剂中毒试验和原位 FTIR 光谱（使用 ReactIR）研究了非均相催化机理，并提出了催化剂的失活动力学，通过 TEM、SEM、Raman 和 XRD 分析其化学稳定性表明，在表面上发生了非均相催化过程，在回收过程中催化活性的变化与催化剂表面的微环境有关。
