A new mesoporous Cu-MPTA-1 nanocatalyst has been synthesized via a simple and facile in situ radical polymerization of triallylamine in the presence of an organic–organic self-assembly of anionic surfactant SDS, followed by grafting of Cu(II) at room temperature under an inert atmosphere. This nanomaterial has been characterized by elemental analysis, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), UV–vis diffuse reflectance spectroscopy (DRS), thermogravimetric analysis (TGA), N2 adsorption–desorption studies, X-ray photoelectron spectroscopy (XPS) and EPR spectroscopy. Cu-MPTA-1 acts as an efficient heterogeneous nanocatalyst exhibiting a high catalytic activity for N-arylation and S-arylation reactions using water as a green solvent and also exhibits an excellent catalytic activity for the one-pot synthesis of propargylamines via a three component coupling of an alkyne, an amine and an aldehyde at room temperature. Moreover, the catalyst is easily recoverable and can be reused six times without an appreciable loss of catalytic activity in the three component coupling reaction. The highly dispersed Cu(II) sites in the Cu-grafted mesoporous polymer could be responsible for the observed high activities of the Cu-MPTA-1 catalyst in the coupling reactions. No evidence of leached Cu from the catalyst during the course of the reaction has been observed, suggesting true heterogeneity in the catalytic process.
一种新型中孔Cu-M
PTA-1纳米催化剂通过在阴离子表面活性剂
SDS的有机-有机自组装存在下,简单易行的原位自由基聚合
三烯胺合成,并在惰性气氛下于室温下接枝Cu(II)而制得。该纳米材料通过元素分析、粉末X射线衍射(XRD)、透射电子显微镜(
TEM)、傅里叶变换红外光谱(FT-IR)、紫外-可见漫反射光谱(DRS)、热重分析(TGA)、氮气吸附-脱附研究、X射线光电子能谱(XPS)和电子顺磁共振光谱(EPR)进行了表征。Cu-M
PTA-1作为一种高效的异相纳米催化剂,展现出对N-芳基化和S-芳基化反应的高催化活性,并使用
水作为绿色溶剂,同时对于通过
炔烃、胺和醛的三组分耦合在室温下合成
丙炔胺的单锅合成也表现出优异的催化活性。此外,该催化剂容易回收,并且在三组分耦合反应中可以重复使用六次而催化活性几乎没有显著损失。Cu接枝中孔聚合物中高度分散的Cu(II)位点可能是Cu-M
PTA-1催化剂在耦合反应中所观察到的高活性的原因。在反应过程中未观察到催化剂中有Cu溶出,表明催化过程具有真正的异相性。