Synthesis of Chitosan-La2O3 Nanocomposite and Its Utility as a Powerful Catalyst in the Synthesis of Pyridines and Pyrazoles

Abstract

Recently, the development of nanocatalysts based on naturally occurring polysaccharides has received a lot of attention. Chitosan (CS), as a biodegradable and biocompatible polysaccharide, is considered to be an excellent template for the design of a hybrid biopolymer-based metal oxide nanocomposite. In this case, lanthanum oxide nanoparticles doped with chitosan at different weight percentages (5, 10, 15, and 20 wt% CS/La2O3) were prepared via a simple solution casting method. The prepared CS/La2O3 nanocomposite solutions were cast in a Petri dish in order to produce the developed catalyst, which was shaped as a thin film. The structural features of the hybrid nanocomposite film were studied by FTIR, SEM, and XRD analytical tools. FTIR spectra confirmed the presence of the major characteristic peaks of chitosan, which were modified by interaction with La2O3 nanoparticles. Additionally, SEM graphs showed dramatic morphological changes on the surface of chitosan, which is attributed to surface adsorption with La2O3 molecules. The prepared CS/La2O3 nanocomposite film (15% by weight) was investigated as an effective, recyclable, and heterogeneous base catalyst in the synthesis of pyridines and pyrazoles. The nanocomposite used was sufficiently stable and was collected and reused more than three times without loss of catalytic activity.

Bio-Based (Chitosan-ZnO) Nanocomposite: Synthesis, Characterization, and Its Use as Recyclable, Ecofriendly Biocatalyst for Synthesis of Thiazoles Tethered Azo Groups

“…The simple coprecipitation method was used to prepare Chitosan-ZnO (CS/ZnO) nanocomposite films containing chitosan as a biostabiliser [ 24 , 25 ]. The films were also characterized by FTIR, SEM, EDX, and XRD tools.…”

“…Due to these factors, the problem has been addressed by doping ZnO in chitosan to produce a heterogeneous, stable, recyclable base catalyst capable of improving some investigated organic reactions. Continuing our work in heterogeneous nanocatalysis [ 1 , 2 , 3 , 23 , 24 ], a heterogeneous basic catalyst based on ZnO nanoparticles immobilized on chitosan ( Figure 1 ) was employed in this study to synthesize thiazole-tethered azo groups.…”

Nanocatalysts: applications for the synthesis of N-containing five-membered heterocycles

“…Over, the results revealed that for the reaction chitosan/La 2 O 3 is better in acting capably as a basic promoter due to its synergistic effect and also due to its simplicity of recovery and recycling. 49 …”

Development of chitosan by using a zeolite‐supported CaO derived from waste chicken eggshell to remove Acid Red 1 dye from the aqueous solution

“…The literature has thoroughly explored and widely reported on the chemical alterations that result in the development of chitosan derivatives, grafting chitosan, and chitosan composites, which have attracted significant interest. 15,16 The creation of nanocomposite adsorbents with excellent catalytic adsorption capabilities has advanced the fields of nanoscience and nanotechnology. Nanoadsorbents have tiny size due to the size quantization effect, resulting in a high surface area to volume ratio, and possess significant catalytic potential and reactivity.…”