Phosphomolybdic acid immobilized chitosan/Fe3O4: an efficient catalyst for the N-alkylation of anilines

Abstract

In this work, phosphomolybdic acid immobilized on chitosan/Fe3O4 as a green catalyst was used for the Hofmann Nalkylation of aniline derivatives with alcohols. H3PMo12O40/chitosan/Fe3O4 (PMo/Chit/Fe3O4) was prepared from the phosphomolybdic acid, chitosan, and Fe3O4 MNPs. Several secondary amines were synthesized from primary arylamines with electron-donating, electron-withdrawing groups, and alcohols in good to excellent yields. The catalyst could be separated using an external magnet and recovered without reducing its catalytic activity. The optimization of the reaction conditions was evaluated using the response surface method (RSM), involving the Box-Behnken design matrix. The simple procedure, only one byproduct (i.e., water), good to excellent yields, easy separation of the catalyst, short reaction times, and environmentally benign conditions were some advantages of this method.

3‐Amino‐5‐mercapto‐1,2,4‐triazole‐functionalized Fe3O4 magnetic nanocomposite as a green and efficient catalyst for synthesis of bis(indolyl)methane derivatives

“…Following increasing interest in the green and efficient synthesis of heterocyclic compounds, 41–44 in the study presented here a convenient method was introduced for the synthesis of bis(indolyl)methane derivatives in the presence of Fe 3 O 4 /SiO 2 /PTS/AMTA as a novel magnetic catalyst (Scheme 1).…”

Controlled synthesis of SPION@SiO2 nanoparticles using design of experiments

“…29 Despite their identification as important experimental conditions in the formation of SPION@SiO 2 NPs, these parameters have not been investigated through a DoE approach, which allows for the simultaneous variation of experimental factors. 72,[76][77][78] This not only enables the evaluation of interactions between these factors, but also reduces the impact of random variation. Furthermore, by implementing 3 levels (low, centre, high), nonlinear effects can also be measured.…”

“…71 There have been several successful examples of the optimisation of nanoparticle synthesis and maximising their functionality using a DoE approach in the literature. 23,[72][73][74][75][76][77][78][79][80] While DoE has proved a powerful tool for nanoparticle optimisation, this approach has not been applied in the context of SPION@SiO 2 NP synthesis. Herein, we implement a statistical approach to understand and predict the influence experimental factors have on the properties of SPION@SiO 2 NPs formed via a reverse microemulsion method.…”

A comprehensive review on synthesis of dihydropyrimidione via Biginelli reaction catalyzed by reusable magnetic nanocatalyst (from 2020–till date)

“…To develop environmentally friendly processes in green synthetic chemistry, the fusion of magnetic nanocatalysts and MCRs will emerge into a new strategic research area. Numerous studies have published research that shows combining MCRs and nanocomposites in ambient reaction circumstances provides improved results with high efficiency for organic synthesis and transformation, such as organic transformation [ 9 ] ; pyranopyrazole and pyranopyrimidine derivatives [ 10 ] ; mono and bis spiro pyrazolopyridines [ 11 ] ; tetrahydrobenzo[a]xanthene‐11‐ones [ 12 ] ; amidoalkyl naphthols [ 13 ] ; xanthene derivatives [ 14 ] ; cross‐aldol condensation [ 15 ] ; 2‐amino‐4 H pyran derivatives [ 16 ] ; [1,3]‐oxazole and 1 H ‐pyrrolo‐[1,3]‐oxazole derivatives [ 17 ] ; 6‐amino‐5‐[(4‐hydroxy‐2‐oxo2 H ‐chromen‐3‐yl)(aryl)methyl]‐1,3‐dimethyl‐2,4,6(1 H ,3 H )‐pyrimidinedione derivatives [ 18 ] ; chromeno‐pyrido[ d ]pyrimidine derivatives [ 19 ] ; spiro[indole‐quinazoline] derivatives [ 20 ] ; cyclocondensation reaction of 4‐hydroxycoumarin, 3,4‐methylenedioxyphenol, and aromatic aldehydes [ 21 ] ; azo chromene dyes [ 22 ] ; cyanopyrroloazepine derivatives [ 23 ] ; 1,3‐dipolar cycloaddition reaction [ 24 ] ; 2,4,5‐triaryl‐1 H ‐imidazoles [ 25 ] ; quinazolinone derivatives [ 26 ] ; tetrahydrobenzoxanthenones [ 27 ] ; α‐aminonitriles [ 28 ] ; chromenes derivatives [ 29,30 ] ; α‐aminonitriles and 2‐methoxy‐2‐phenylacetonitrile derivative via Strecker‐type reaction [ 31 ] ; dihyropyrimidiones [ 32 ] ; dihydroquinazolinone, octahydroquinazolinone, and benzimidazoloquinazolinone derivatives [ 33 ] ; quinazolines [ 34 ] ; 1‐thioamidoalkyl‐2‐naphthols [ 35 ] ; hexahydroquinoline [ 36 ] ; benzoxanthenes [ 37 ] ; and polyhydroquinoline. [ 38 ]…”