In the present study, a novel magnetic carbon nanotube functionalized by chlorosulfonicacid (Fe₃O₄‐CNT‐SO₃H) with nanotube morphology decorated by the spherical nanoparticles was prepared, characterized and introduced as a retrievable magnetic heterogeneous nanocatalyst for green synthesis a variety of 2‐(1H ‐tetrazole‐5‐yl) acrylonitrile via multicomponent domino Knoevenagel condensation/ 1,3‐dipolar cycloaddition reaction between aromatic aldehydes, malononitrile, and sodium azide under solvent free conditions. The catalyst was magnetically separated from the reaction system by an outer magnetic force and recycled up to five runs without a remarkable loss in its efficiency. The as‐preparedacidic magnetic nanocomposite was characterized by different techniques inclusive Fourier transform infrared, thermogravimetric analysis, energy dispersive X‐ray, field emission scanning electron microscopy, X‐ray diffraction, vibrating sample magnetometry, CHNS elemental analysis, and acid‐base titration. Easy workup, affordability, elimination of volatile and toxic solvents, and high yield of products are some merits of this protocol.

中文翻译：

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磁性碳纳米管是磺酸杂化的高度稳定且可回收的载体，可用于合成2-（1H-四唑-5-基）丙烯腈衍生物

在本研究中，制备了一种新型的被碳磺酸功能化的磁性碳纳米管（Fe ₃ O ₄ -CNT-SO ₃ H），其球形纳米颗粒修饰了纳米管的形态，并表征为可回收的磁性非均相纳米催化剂，用于绿色合成各种的2-（1 H在无溶剂条件下，通过芳族醛，丙二腈和叠氮化钠之间的多组分多米诺骨牌Knoevenagel缩合反应/ 1,3-偶极环加成反应生成4-四唑-5-基）丙烯腈。通过外磁力将催化剂与反应体系磁分离，并循环多达五次运行，而效率没有明显损失。所制备的酸性磁性纳米复合材料的特征在于不同的技术，包括傅立叶变换红外光谱，热重分析，能量色散X射线，场发射扫描电子显微镜，X射线衍射，振动样品磁力分析，CHNS元素分析和酸碱滴定。易于操作，价格适中，消除挥发性和有毒溶剂以及产品高收率是该协议的优点。