Gold Modified Zeolite: An Efficient Heterogeneous Catalyst for <I>N</I>-Arylation of Indazole
作者:P Emayavaramban、K Kadirvelu、N Dharmaraj
DOI:10.1166/jnn.2016.12905
日期:2016.9.1
We herein report N-arylation of indazole with aryl halides using gold modified zeolites (Au-zeolites) as an efficient catalytic system. Au-zeolites with three different gold loading were prepared by ion-exchange method and characterized by UV-visible diffuse reflectance spectroscopy (UV-DRS), transmission electron microscopy and energy-dispersive X-ray spectroscopy (TEM-EDX) and X-ray photoelectron spectroscopy (XPS). The Brunauer-Emmett-Teller (BET) and Langmuir surface areas of the prepared Au(5)-zeolite catalyst were found to be 644 and 929 m2g−1 respectively. Goldmodified zeolites performed as an efficient catalytic system for N-arylation of indazole using diverse aryl halides afforded N1 arylated products in appreciable yield under mild reaction conditions. The catalyst was reusable for at least five times with only a marginal loss of activity. This simple, effective and environmentally benign heterogeneous protocol provides a safer alternative to hazardous, corrosive and more polluting conventional catalysts.
我们在此报告使用金修饰沸石(Au-zeolites)作为高效催化体系,对吲唑与芳基卤化物进行 N-芳基化反应。我们采用离子交换法制备了三种不同金负载的金沸石,并通过紫外可见漫反射光谱(UV-DRS)、透射电子显微镜和能量色散 X 射线光谱(TEM-EDX)以及 X 射线光电子能谱(XPS)对其进行了表征。制备的金(5)沸石催化剂的布鲁纳-艾美特-泰勒(BET)和朗缪尔表面积分别为 644 和 929 m2g-1。金改性沸石是一种高效的催化体系,可在温和的反应条件下,利用各种芳基卤化物对吲唑进行 N-芳基化反应,并以可观的产率获得 N1 芳基化产物。该催化剂可重复使用至少五次,活性仅略有下降。这种简单、有效和对环境无害的异构方案为危险、腐蚀性和污染性更强的传统催化剂提供了更安全的替代品。