Copper ferrite nanoparticle modified starch as a highly recoverable catalyst for room temperature click chemistry: multicomponent synthesis of 1,2,3-triazoles in water

A new magnetic catalyst comprising starch-supported CuFe2O4 NPs as a highly water dispersible material is prepared and characterized by different techniques such as TEM, SEM, VSM, EDX-mapping, XPS, and TG analyses. The obtained CuFe2O4@Starch is applied as a heterogeneous catalyst in click chemistry for the three-component synthesis of 1,2,3-triazoles in water at room temperature with low copper loading (0.1 mol%). Using this catalyst, benzylic halides, alkyl bromides and arylboronic acids reacted with sodium azide and terminal alkynes giving 1,4-disubstituted 1,2,3-triazoles in high yields. The catalyst can be easily separated from the reaction mixture using an external magnet and reused for at least 11 consecutive runs with a slight drop in its catalytic activity. The reused catalyst was characterized by TEM, VSM and XPS analysis showing similar structure to the fresh catalyst with a slight decrease of the magnetization value and small aggregations of nanoparticles.The authors are grateful to the Institute for Advanced Studies in Basic Sciences (IASBS) Research Council, Zanjan University and Iran National Science Foundation (INSF-Grant number of 95844587) for support of this work. The authors are also thankful to the Spanish Ministerio de Economia y Competitividad (MINECO) (projects CTQ2013-43446-P and CTQ2014-51912-REDC), the Spanish Ministerio de Economía, Industria y Competitividad, Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER, EU) (projects CTQ2016-76782-P and CTQ2016-81797-REDC), the Generalitat Valenciana (PROMETEO2009/039 and PROMETEOII/ 2014/017) and the University of Alicante

Stabilization of gold nanoparticles on copper ferrrite and its application as bimetallic and magnetically recyclable catalyst for preparation of propargylamines

In this report for the first time, gold nanoparticles were supported and stabilized on copper ferrite nanoparticles (CuFe2O4 NPs) and obtained compound was characterized by different techniques such as transmission electron microscopy (TEM), X-ray spectroscopy (EDS) mapping, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA) and X-ray diffraction (XRD) . Novel prepared material has been applied as a bimetallic and magnetic catalyst in successful coupling reaction of structurally different aldehydes, amines and alkynes for preparation of various propargylamines. Using this catalyst, corresponding propargylamines were obtained in high to excellent yields. Catalyst was successfully recovered by external magnetic field and reused for 6 consecutive runs without decreasing of activity

Gold Nanoparticles Supported on Imidazole‐Modified Bentonite: Environmentally Benign Heterogeneous Catalyst for the Three‐Component Synthesis of Propargylamines in Water

Gold nanoparticles supported on imidazole‐modified bentonite, Bent@Im@Au NPs, has been developed for the first time as an effective heterogeneous catalyst for the synthesis of propargylamines under mild reaction conditions in water at a loading of 0.07 mol % of Au. Various techniques such as X‐ray diffraction, high‐resolution transmission electron microscopy, Fourier transform infrared spectroscopy, and element mapping by scanning electron microscopy were used to determine the physicochemical properties of the catalysts. The new gold catalyst was found to be highly active providing high to excellent yields of A3 coupling products via the reactions of various aldehydes, having electron‐withdrawing as well as electron‐donating substituents, with different amines and alkynes. The catalysts can be easily recovered and reused without significant loss of activity and the recycled catalyst was characterized.We are grateful to the Institute for Advanced Studies in Basic Sciences (IASBS) Research Council and Iran National Science Foundation (INSF-Grant number of 95844587) for support of this study. C.N. is also thankful for financial support from the Spanish Ministerio de Economía y Competitividad (MINECO) (projects CTQ2013-43446-P and CTQ2014-51912-REDC), the Spanish Ministerio de Economía, Industria y Competitividad, Agencia Estatal de Investigación (AEI), the Fondo Europeo de Desarrollo Regional (FEDER, EU) (projects CTQ2016-76782-P and CTQ2016-81797-REDC), the Generalitat Valenciana (PROMETEOII/2014/017), and the University of Alicante

CuCl 2 heterogenized on metformine-modified polystyrene resin as an antibacterial agent and recyclable nanocatalyst for Ullmann-type C-N coupling reactions

Merrifield Resin was functionalized with metformine and applied as a solid support to immobilize the CuCl 2 . The Ps-Met/CuCl 2 was characterized by several techniques including Fourier transform infrared (FTIR), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), wavelength-dispersive X-ray spectroscopy (WDX) and inductively coupled plasma (ICP). The Ps-Met/CuCl 2 was used as an efficient recyclable solid nanocatalyst for N-arylation of indole and aniline through coupling reactions of Ullmann-type C-N. The advantages of this method are easy workup, improved yields, and simple recovery via filtration. Ultimately, the Ps-Met/CuCl 2 antibacterial property was examined against two bacteria (Staphylococcus aureus (Staph. aureus) and Escherichia coli (E. coli)) and indicated its antibacterial performance against gram negative (E. coli) bacteria and gram positive (Staph. aureus). © 2019 John Wiley & Sons, Ltd