Magnetic carbon nanotube as a highly stable and retrievable support for the heterogenization of sulfonic acid and its application in the synthesis of 2‐(1H‐tetrazole‐5‐yl) acrylonitrile derivatives

Abstract

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.

Nanomaterial catalyzed green synthesis of tetrazoles and its derivatives: a review on recent advancements

“…The Fe 3 O 4 @BNPs-CPTMS-chitosan-Pd(0) offered numerous advantages such as green ligand (Chitosan), thermal and mechanical stability, high-grade magnetic strength, high surface area, reusability (5 cycles), an easy and fast separation. 65 Akbarzadeh et al embedded chlorosulfonic acid functionalized carbon nanotubes on Fe 3 O 4 nanoparticles to produce 66 Similarly, it was found that, unmodied nano Fe 3 O 4 exhibited remarkable catalytic activity for 5-substituted tetrazole synthesis from malononitrile (1 mmol), aromatic aldehyde (1 mmol), sodium azide (1 mmol) as tabulated in Table 4, entry 4. They observed that nano Fe 3 O 4 gave best result at 20 mol% amount.…”

“…Development of copper-based nanomaterials received huge attention in recent years specially in domain of nano-catalysis organic transformations due to its extensive range of oxidation states which can enables reactivity through both one-and two-electron pathways. 66 Also, copper-based nano-materials found applications in various other areas like nanotechnology, electrocatalysis, and photocatalysis. [68][69][70] In this context, Cu-immobilized heterogenous nano-catalysts have been extensively utilized in synthesis of tetrazoles derivatives (Tables 5-8).…”

“…Further tempting to green catalyst, recyclability of Fe 3 O 4 -CNT-SO 3 H is much easier compared to other stated. 66 …”

Easy conversion of nitrogen‐rich silk cocoon biomass to magnetic nitrogen‐doped carbon nanomaterial for supporting of Palladium and its application

“…[38] This paper is a continuation of previous researches on the synthesis and application of new green separable heterogeneous catalysts. [39][40][41][42][43][44] This report shows our efforts to make a novel palladium catalyst using both nitrogendoped carbon materials prepared by hydrothermal carbonization process and as-prepared magnetic Fe 3 O 4 as a support. This combination offers benefits of simple separation, great reusability, and perfect ability to load a considerable amount of palladium.…”