A green, efficient and recoverable CeO₂/MWCNT nanocomposite catalyzed click synthesis of pyridine‐3‐carboxamides

Abstract

A facile, green and environmentally‐friendly protocol for the preparation of ceria doped multi‐walled carbon nanotubes (2.5%CeO2/MWCNTs) composite catalysts are developed. The synthesized catalyst materials have been characterized by using P‐XRD, SEM, TEM and BET analysis. Further, the composite was utilized as a highly efficient and reusable heterogeneous nano‐catalyst for the synthesis of pyridine‐3‐carboxamide derivatives by multicomponent condensation of acetoacetanilide, ammonium acetate, substituted aromatic aldehyde and ethyl cyanoacetate via one‐pot reaction under ethanol solvent conditions at R.T. The remarkable advantages of this green protocol exhibits operational simplicity, easy workup procedure, inexpensive, evading of toxic solvents, shorter reaction times (≤ 15 mins), excellent yields and also avoidance of column chromatography. Furthermore, the catalyst was recyclable and reusability endured for a minimum of six consecutive cycles without significant loss in the catalytic activity.

Improved Microwave Absorption Performance with Sustainable Porous Carbon/Carbon Nanotube Composites

“…The specific surface area showed a typical value for the CNT, around 100 m 2 /g [46][47][48] , while the PC showed no developed micro or mesoporosity (pores lesser than 50 nm) presenting a value of 11 m 2 /g (Table 1). The latter agrees with the porosity seen by SEM images, where macropores (pores larger than 50 nm) are observed.…”

Recyclable catalysts for the synthesis of heterocyclic compounds using carbon materials

“…It was noted that the presence of either MWCNT or Mn 3 O 4 alone could catalyze this three‐component reaction, and low yields of quinolines (68% and 77%) were observed. [35] In addition, recyclability of this heterogeneous catalyst has been studied eight times in a short period of time, 15 min.…”

A simple, safe, eco‐friendly, and unique synthesis of hexahydro‐quinolines employing Fe3O4‐MWCNT@MnO2 as a reusable catalyst

“…46,47 They are renowned for their high surface area, excellent crystallinity, unique porosity, and facilitation of electron transport during reactions. 48,49 Furthermore, because of their global accessibility, non-volatility, chemical and thermal stability, and affordability. 50 Likewise, magnetite nanoparticles are garnering more and more interest because of their distinct nontoxicity, 51 high surface area to volume ratio, biocompatibility, 52 and prospective uses in various industries.…”