When CuAAC 'Click Chemistry' goes heterogeneous

Agarose-supported copper nanoparticles (CuNPs@agarose) were prepared by immobilization of copper bromide on agarose followed by in situ chemical reduction. The new material was characterized by SEM, EDX, TEM, TGA, XRD, nitrogen adsorption–desorption, and solid UV–vis analysis. The catalytic activity of CuNPs@agarose was assessed in the three component click synthesis of 1,2,3-triazoles in water under low catalyst loading and mild reaction conditions. The easy synthesis and air-stable catalyst was recycled for five runs with small drops in catalytic activity.

Copper Nanoparticles Supported on Agarose as a Bioorganic and Degradable Polymer for Multicomponent Click Synthesis of 1,2,3-Triazoles under Low Copper Loading in Water

The azide–alkyne cycloaddition reaction was investigated under catalytic conditions involving a copper(II) loaded silica based mesoporous material. Cu(II) SBA-15 demonstrated a high catalytic effect in 1,4-triazoles synthesis in organic. No additives such as a base or a reductant are required. Quantitative yields were obtained and a mere filtration of the mesoporous material which retains copper(II) allows the recovery of the catalyst. In addition, up to 5 times recycling of the catalyst was achieved without loss of the activity affording 1,4-triazoles in a yield up to 98%.

Copper(II) SBA-15: A reusable catalyst for azide–alkyne cycloaddition

During the polymerization of aniline using copper sulphate, act as an oxidizing agent, the in-situ synthesized Cu(I) ion catalyzed the cyclo-addition between azides and alkynes. This work represents the merging of two steps, synthesis of the catalyst and application of the catalyst, in a one pot reaction. The elimination of the separate catalyst synthesis step is economic in terms of cost and time. As aniline was used as one of the reactant components so there is no requirement to use additional base for this reaction that further eliminates the cost of the process. Again, the catalyst can be readily recovered by filtration and efficiently used for the several sets of reactions without any significant loss of catalytic activity.

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Polymer immobilized Cu(I) formation and azide-alkyne cycloaddition: A one pot reaction.

This review focuses, on the application of nanomaterials as heterogeneous catalysts for the synthesis of different heterocyclic systems. We pay special attention to the specific synthesis of such systems in an organized manner with respect to the type of the heterocyclic systems.

Synthesis of heterocycles and fused heterocycles catalyzed by nanomaterials

A facile and simple protocol for the 1,3-dipolar cycloaddition of organic azides with terminal alkynes catalyzed by doped nano-sized Cu2O on melamineformaldehyde resin (nano-Cu2OMFR) as a new and convenient heterogeneous catalyst is described. In this method, ‘click’ cycloaddition of various structurally diverse β-azido alcohols and alkynes in the presence of nano-Cu2OMFR in H2O/THF 1 : 2 furnished the corresponding 1,4-disubstituted 1H-1,2,3-triazole adducts 1a–1o in good to excellent yields at room temperature (Scheme and Table 3). The nano-Cu2OMFR was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), inductively coupled plasma (ICP) analysis, and FT-IR. The nano-Cu2OMFR could be easily recovered and recycled from the reaction mixture and reused for many consecutive trials without significant decrease in activity (Table 4). The in vitro antibacterial activities of all synthesized compounds were tested on several Gram-positive and/or Gram-negative bacteria (Table 5). The results demonstrate the promising antibacterial activity for some of the synthesized compounds.

Doped Nano-Sized Copper(I) Oxide (Cu2O) on MelamineFormaldehyde Resin: a Highly Efficient Heterogeneous Nano Catalyst for ‘Click’ Synthesis of Some Novel 1H-1,2,3-Triazole Derivatives Having Antibacterial Activity

Abdol-Rasoul Ahmadi Gandomani

Papers

Doped Nano-Sized Copper(I) Oxide (Cu2O) on MelamineFormaldehyde Resin: a Highly Efficient Heterogeneous Nano Catalyst for ‘Click’ Synthesis of Some Novel 1H-1,2,3-Triazole Derivatives Having Antibacterial Activity