Highly efficient protocol for the aromatic compounds nitration catalyzed by magnetically recyclable core/shell nanocomposite

An efficient three‐component reaction of aromatic aldehydes, 6‐aminouracil/6‐amino‐1,3‐dimethyluracil and 4‐hydroxycoumarin in the presence of a novel heterogeneous catalyst H3PMo12O40‐immobilized Co3O4/chitosan led to a synthesis of a new class of pyrimidinedione derivatives under reflux conditions. The magnetically recoverable nanocomposite of Co3O4/chitosan/H3PMo12O40 was fully characterized by Fourier transform‐infrared spectrophotometry, scanning electron microscopy, X‐ray powder diffraction, energy‐dispersive X‐ray spectroscopy, vibrating‐sample magnetometry and N2 adsorption–desorption by Brunauer–Emmett–Teller analysis. Results show that Keggin‐type 12‐molybdophosphoric acid immobilized into the network of the cross‐linked chitosan with super‐paramagnetic Co3O4 nanoparticles. The present method offers several advantages, such as simple procedure, short reaction times and excellent yields of products. The novelty of the catalyst, high catalytic activity, easy separation from the reaction with an external magnetic field and reusability of the catalyst in six consecutive runs are additional eco‐friendly attributes of this catalytic system.

Section: Introductionmentioning

confidence: 99%

H₃PMo₁₂O₄₀‐immobilized chitosan/Co₃O₄: A novel and recyclable nanocomposite for the synthesis of pyrimidinedione derivatives

Safari

Tavakoli

Ghasemzadeh

2019

“…In recent decade, SPIONs, as a main group of separation materials, has drawn significant attention to itself in chemistry and material science, due to its crucial applications in manufacturing catalysts for the synthesis of various biological active compounds. In addition, SPIONs has excellent properties such as magnetism and insolubility that enable the catalyst to be easily separated with an external magnetic field and reused frequently without considerable loss of catalytic activity …”

Section: Introductionmentioning

confidence: 99%

Surface modified SPIONs‐Cr(VI) ions‐immobilized organic‐inorganic hybrid as a magnetically recyclable nanocatalyst for rapid synthesis of polyhydroquinolines under solvent‐free conditions at room temperature

Maleki

Hamidi

Maleki

et al. 2018

Self Cite

In this work, a magnetic hybrid dichromate nanocomposite with triphenylphosphine surface modified superparamagnetic iron oxide nanoparticles (SPIONs) as a recyclable nanocatalyst was designed, prepared and characterized by Fourier transform infrared spectroscopy (FT-IR) spectra, X-ray diffraction (XRD) pattern analysis, vibrating sample magnetometer (VSM) curves, X-ray fluorescence (XRF) analysis, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images and dynamic light scattering (DLS) analysis. Then, it was used in a green and efficient procedure for one-pot multicomponent synthesis of polyhydroquinoline derivatives by the condensation of aldehydes, dimedone or 1,3-cyclohexadione, ethyl acetoacetate and ammonium acetate. This protocol includes some new and exceptional advantages such as short reaction times, low catalyst loading, high yields, solvent-free and room temperature conditions, easy separation and reusability of the catalyst.

“…Biodegradability, eco ‐ friendly and relatively low price of cellulose are some major reasons for its usage in the composite nanostructures . Therefore, magnetic nanocomposites based on cellulose can be regarded as a green and efficient recoverable and biodegradable nanocatalyst …”

Section: Introductionmentioning

confidence: 99%

Facile one‐pot synthesis of a series of 7‐aryl‐8H‐benzo[h]indeno[1,2‐b]quinoline‐8‐one derivatives catalyzed by cellulose‐based magnetic nanocomposite

Maleki

Yeganeh

2017

Self Cite

A sulfonated magnetic cellulose-based nanocomposite was applied as an efficient, inexpensive and green catalyst for the one-pot three-component synthesis of 7-aryl-8H-benzo[h]indeno[1,2-b]quinoline-8-ones starting from 1,3-indanedione, aromatic aldehydes and 1-naphthylamine under solvent-free conditions in high yields (79-98%) within short reaction times (2-5 min). The nanobiostructure catalyst can be easily separated from the reaction mixture by using an external magnet and reused several times.