Synthesis and Characterization of Copper(I)‐Cysteine Complex Supported on Magnetic Layered Double Hydroxide as an Efficient and Recyclable Catalyst System for Click Chemistry Using Choline Azide as Reagent and Reaction Medium

Copper supported modified magnetic carrageenan as a bio-based catalyst for the synthesis of novel scaffolds bearing the 1,2,3-triazole unit through the click reaction

The ongoing work delineates the design of a novel library of 1,2,3-triazole-attached phenylacetamides through molecular hybridization of propargyl and phenylacetamide derivatives. Copper-supported modified magnetic carrageenan serves as a green heterogeneous catalyst, ensuring high yield, efficient reaction times, high atom economy, utilization of an environmentally friendly catalyst from a natural source, and a straightforward workup procedure. The successful synthesis of the catalyst is confirmed and evaluated using various analytical techniques, while the synthetic compounds are characterized through 1H NMR and 13C NMR.

Modified nano magnetic Fe2O3-MgO as a high active multifunctional heterogeneous catalyst for environmentally beneficial carbon-carbon synthesis

In this study, novel nanomagnetic catalysts, namely Fe2O3-MgO@choline formate (Ch. F.) and Fe2O3-MgO@choline cyanide (Ch. CN), were synthesized through immobilizing choline-based ion liquids to magnetic support via a simple and cost-effective methodology. FT-IR, TGA, FE-SEM, VSM, EDS, BET, and XRD techniques were employed to assess and characterize these organic-inorganic compounds. Following the successful preparation of nanoparticles, the catalysts were utilized in Knoevenagel and benzoin condensations. Fe2O3-MgO@Ch.F. exhibited exceptional activity in Knoevenagel condensation under solvent-free conditions at room temperature, achieving high yields (91-98%) in a short timeframe. Similarly, Fe2O3-MgO@Ch.CN demonstrated remarkable activity in benzoin condensation under environmentally friendly solvent conditions, yielding higher isolated yields (76-88%). Furthermore, these magnetically recyclable multifunctional catalysts displayed the ability to be reused up to five times without a significant loss in efficiency. Additionally, the heterogeneity of this nanocatalyst was investigated using the hot filtration technique. The findings indicated that the reaction primarily occurs via a heterogeneous pathway.

CuFe2O4@SiO2@L-arginine@Cu(I) as a new magnetically retrievable heterogeneous nanocatalyst with high efficiency for 1,4-disubstituted 1,2,3-triazoles synthesis

A novel magnetic heterogeneous catalyst was synthesized through the immobilization of copper ions onto the l-arginine functionalized CuFe₂O₄@SiO₂. The prepared catalyst was characterized by Fourier Transform Infrared (FT-IR), X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), and Energy Dispersive X-Ray spectroscopy (EDX). The resulting catalyst was used in the ultrasonic-assisted synthesis of 1,2,3-triazoles via a one-pot three-component reaction of alkynes, alkyl halides, and sodium azides under green conditions within a short time. The catalyst reusability was investigated after five cycles and no significant loss of activity was observed.

Recent Advances in Copper-Based Solid Heterogeneous Catalysts for Azide-Alkyne Cycloaddition Reactions

The copper(I)-catalyzed azide−alkyne cycloaddition (CuAAC) reaction is considered to be the most representative ligation process within the context of the “click chemistry” concept. This CuAAC reaction, which yields compounds containing a 1,2,3-triazole core, has become relevant in the construction of biologically complex systems, bioconjugation strategies, and supramolecular and material sciences. Although many CuAAC reactions are performed under homogenous conditions, heterogenous copper-based catalytic systems are gaining exponential interest, relying on the easy removal, recovery, and reusability of catalytically copper species. The present review covers the most recently developed copper-containing heterogenous solid catalytic systems that use solid inorganic/organic hybrid supports, and which have been used in promoting CuAAC reactions. Due to the demand for 1,2,3-triazoles as non-classical bioisosteres and as framework-based drugs, the CuAAC reaction promoted by solid heterogenous catalysts has greatly improved the recovery and removal of copper species, usually by simple filtration. In so doing, the solving of the toxicity issue regarding copper particles in compounds of biological interest has been achieved. This protocol is also expected to produce a practical chemical process for accessing such compounds on an industrial scale.

Development and functionalization of magnetic nanoparticles as stable and reusable catalysts for triacetin synthesis

Applications of magnetic nanoparticles as catalyst support has recently received great attention due to their unique properties, such as high surface area, ease of anchoring, high stability and ease of separation under an external field.