Cascade synthesis of fused polycyclic dihydropyridines by Ni–Zn–Fe hydrotalcite (HT) immobilized on silica-coated magnetite as magnetically reusable nanocatalyst
摘要:
本研究开发了一种高效的生态友好型方法,用于一锅多组分合成融合多环二氢吡啶(DHP)衍生物。在无溶剂条件下,使用异质核壳 Fe3O4@SiO2@Ni-Zn-Fe 水合金属氧化物对芳香醛、4-羟基香豆素和醋酸铵进行串联缩合,以高收率到极高收率获得相应产物。利用扫描电子显微镜结合能量色散 X 射线分析(SEM-EDX)、粉末 X 射线衍射分析、透射电子显微镜(TEM)和布鲁瑙尔-艾美特-泰勒技术对纳米磁性层状双氢氧化物进行了表征。此外,还通过 TEM 和 SEM 分析研究了绿色水滑石的可回收性。目前的研究重点是开发一种在温和条件下不使用有害溶剂合成 DHPs 的绿色方法。
Abstract In this study, the immobilization of sulfonicacid on silica-layered nickel ferrite, NiFe2O4@SiO2@SO3H, was investigated. The sulfonated Ni-nanocatalyst was then characterized using FT-IR, SEM, EDX, XRD and VSM analyses. Catalytic activity of the Ni-nanocomposite was also studied towards Hantzsch synthesis of 1,4-dihydropyridines via one-pot condensation reaction of 1,3-diketones (ethyl acetoacetate
Sulfonyl-bridged (copper-immobilized nickel ferrite) with activated montmorillonite, [(NiFe<sub>2</sub>O<sub>4</sub>@Cu)SO<sub>2</sub>(MMT)]: a new class of magnetically separable clay nanocomposite systems towards Hantzsch synthesis of coumarin-based 1,4-dihydropyridines
作者:Behzad Zeynizadeh、Soleiman Rahmani
DOI:10.1039/c9ra00177h
日期:——
In this study, the synthesis of a new class of magnetic clay-based nanocomposites by bridging of sulfonyl groups between copper-immobilized nickel ferrite (NiFe2O4@Cu) and activated montmorillonite is described. Synthesis of the clay nanocatalyst was carried out via the activation of montmorillonite by ClSO3H to afford sulfonated montmorillonite. The modified montmorillonite was then reacted with copper-layered
在这项研究中,描述了通过在铜固定的镍铁氧体 (NiFe 2 O 4 @Cu) 和活化蒙脱石之间桥接磺酰基来合成一类新型磁性粘土基纳米复合材料。粘土纳米催化剂的合成是通过ClSO 3 H活化蒙脱石得到磺化蒙脱石。然后将改性蒙脱石与铜层镍铁氧体反应,得到磁性粘土纳米复合材料[(NiFe 2 O 4 @Cu)SO 2(MMT)]。接下来,使用扫描电子显微镜、能量色散 X 射线光谱、X 射线衍射、傅里叶变换红外光谱、Brunauer-Emmett-Teller 和振动样品磁力计分析对多孔材料进行了表征。所得结果表明,与制备的不含磺酰基的粘土纳米复合材料(NiFe 2 O 4 @Cu)(MMT)相比,含有磺酰基桥的粘土纳米复合材料具有较大的表面积和磁性。纳米结构粘土对Hantzsch合成香豆素基1,4-二氢吡啶具有优异的催化活性。4-羟基香豆素、芳香醛和氨的一锅三组分缩合。所有反应均在水中作为绿色和经济的绿色溶剂在
A New MCR Strategy Generating a Collection of Skeletally Diverse Simple Molecules Combinatorially
作者:Sibaji Nandi、Ajay Gupta、Amarta Kumar Pal
DOI:10.2174/1570178614666170221125300
日期:2017.6.8
aim was to develop an alternative platform for the synthesis of a collection of the small molecules with high scaffold diversity. Our methods based on Lewis acid catalyzed one-pot synthesis of 1,4-DHP, pyrimido[4,5-b]quinoline and chromeno[4,3-b]quinoline derivatives under room temperature stirring or refluxing condition. Results: We have standardized a protocol for the synthesis of a library of heterocycles
Abstract An efficient and eco-friendly protocol for the synthesis of polycyclic dihydropyridine scaffolds has been developed from readily accessible 4-hydroxycoumarin, aldehydes, and ammonium acetate in the presence of guanidinium-based sulfonic acid as a Brønstedacidorganocatalyst. This method provides several advantages, such as simple work-up procedure, environmentally benign, recyclable catalyst