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K2CO3/Glycerin as a deep eutectic solvent (DES) was anchored covalently onto functionalized magnetic nanoparticles and showed a significant activity towards the oxidation of various alcohols under mild conditions with a short reaction time and good to high yield. A combination of the magnetic nanoparticles and deep eutectic solvent offers a novel, green, reusable catalyst with easy separation. Also, the catalyst structure was well characterized using techniques such as FT‐IR spectroscopy, XRD, SEM, TGA, BET, VSM, TEM, and energy‐dispersive X‐ray spectroscopy (EDS). [ABSTRACT FROM AUTHOR]

In this paper, a bifunctional ligand containing two mutually acidic and basic sites was successfully immobilized on magnetic nanoparticles. The prepared nanocatalyst was analyzed by various techniques such as Fourier transform infrared spectroscopy (FT‐IR), field emission scanning electron microscope (FE‐SEM), vibrating sample magnetometer (VSM), thermal analysis (TGA), and X‐ray diffraction (XRD). This novel easy‐prepared catalyst gave excellent efficiency in Aldol and aza‐Michael reactions in green and mild reaction conditions. The applicability of the introduced catalytic system was also studied successfully in the large‐scale synthesis of derivatives of dihydroquinolines. This procedure possesses many advantages such as simple work‐up, high yield, and short reaction times. [ABSTRACT FROM AUTHOR]

An efficient and retrievable copper(I) catalyst was synthesized by immobilizing of copper iodide on 3‐thionicotinyl‐urea‐modified magnetic nanoparticles and characterized using a variety of analysis techniques. The catalytic activity of these nanoparticles was investigated in the one‐pot three‐component reaction of aryl halides, sodium azide, and terminal alkynes using choline chloride/PEG deep eutectic mixture as a green and recoverable solvent. The PEGylated deep eutectic solvent (DES), due to its favorable polarity and solubility, can make an effective association of polar and non‐polar reactants during the reaction, thereby accelerating the catalysis process. An array of 1‐aryl 1,2,3‐triazoles were obtained in good to excellent yields. The catalyst system can be readily recovered and reused at least five times with no appreciable loss of its activity. [ABSTRACT FROM AUTHOR]

Copper supported on magnetite nanoparticles modified with environmentally friendly ligand tricine was devised for synthesis of acetamides via C–C oxidative cleavage of ketones with amines. The catalyst was characterized using different techniques, including Fourier transform infrared, X‐ray diffraction, scannin electron microscopy, vibrating sample magnetometry, thermogravimetric analysis, and energy dispersive x‐ray spectroscopy. The protocol showed relatively high yields of acetamide products. Furthermore, the magnetic recovery of the catalyst rendered the overall process fast and efficient. It was used in the reaction for six consecutive cycles with negligible loss of catalytic activity. This research is the first report of application of magnetic nanocatalysts for synthesis of acetamides from ketones of low activity through a C–C bond cleavage strategy. [ABSTRACT FROM AUTHOR]

Vitamin B6–Pd(II) immobilized onto magnetic nanoparticles have been successfully prepared and applied for C–Xcross‐coupling reactions with aryl halides in green deep eutectic solvents. The results prove that the Fe3O4@vitamin B6–Pd(II) magnetic nanoparticles show high catalyst activity and good stability. It was also revealed that this complex can be recycled up to five times without any significant loss in catalytic activity. [ABSTRACT FROM AUTHOR]

One‐pot condensation of benzyl alcohol with di‐alkyl/ aryl phosphite under free solvent conditions was investigated in the presence of Fe3O4@SiO2‐Met‐Cu (II) as a recyclable heterogeneous catalyst and aqueous tert‐butyl hydroperoxide (TBHP) as the oxidant. The advantages of this protocol include good to excellent yields, easy workup, short reaction time and good reusability to 4 cycles. Also, interactions between metal and ligand in the Fe3O4@SiO2‐Metformin complex is studied by using theoretical calculations [ABSTRACT FROM AUTHOR]

A useful, robust, and cheap procedure was obtained for the synthesis of 4‐aryl‐NH‐1,2,3‐triazoles via aromatic aldehydes, nitromethane and choline azide in the presence of folic acid immobilized magnetic nanoparticle with good yields. The magnetic catalyst is easily synthesized and can be recycled at least five times with no significant loss in activity. In addition, the choline azide is used as a reagent and green solvent. [ABSTRACT FROM AUTHOR]

A new, powerful and recyclable copper catalyst were prepared by heterogenization of copper chloride using of Fe3O4 nano particles modified with citric acid as a linker. This system can catalyze reduction of nitroaren compound to aniline derivatives in the presence of Sodium borohydride as a reduction agent in moderate to good yields. In addition, easy separation and recoverable with an external permanent magnet is the dominant properties of this catalyst (Cu2+-CA@Fe3O4). [ABSTRACT FROM AUTHOR]

Copper-grafted guanidine acetic acid-modified magnetite nanoparticles (Fe3O4@GAA-Cu(II)) as a green, superparamagnetic and recoverable nanocatalyst is found to promote quantitative N-acylation of various amines in a very short time with an equimolar amount of thioacetic acid in water at room temperature. This method is found to be highly selective for amines and not sensitive to other functional groups. Mild reaction condition, high selectivity, efficiency, simple workup and excellent yields are some of the major advantages of the procedure. [ABSTRACT FROM AUTHOR]

Copper oxide supported on magnetic nanoparticles was used as a green magnetic nanocatalyst for hydroamination of carbodiimides towards the synthesis of guanidines. Easy preparation and separation, low cost, non-sensitivity to moisture and reusability of the catalyst along with diversity and high yield of products are significant features of this method. [ABSTRACT FROM AUTHOR]

Toluene oxidation is one of the substantial industrial technologies since oxidized products are industrially very important intermediates. A Fe3O4@cysteine@Cu-catalysed reaction that uses tert-butyl hydroperoxide as oxidant to produce esters from toluene and β-diketones or β-keto esters, enolate precursors, has been developed. Oxidative esterification of toluene with 1,3-dicarbonyl derivatives led to C─O bond formation and direct C─H functionalization. [ABSTRACT FROM AUTHOR]

Superparamagnetic CuCl nanoparticles were prepared and identified as an effective heterogeneous catalyst for the tandem transformation of methylarenes and 1,3-dicarbonyl compounds into the corresponding enole esters by the use of tert-butyl hydroperoxide as an external oxidant. The catalyst can be removed from the reaction medium simply by use of an external magnet. As a consequence, various derivatives of enol esters were synthesized in moderate to good yields. [ABSTRACT FROM AUTHOR]

A green, benign, heterogeneous, superparamagnetic catalyst (Glu.@Fe3O4) was synthesized and characterized using Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, scanning electron microscopy and vibrating sample magnetometry. The prepared catalyst was used to achieve a high-efficiency, low-cost, eco-friendly and easy-to-handle protocol for synthesizing substituted pyrazole derivatives from aldehydes, malononitrile and phenylhydrazine. The catalyst was also used in chromene synthesis. Glucose coated on magnetic nanoparticles provided excellent catalytic activity. The catalyst could be recycled for up to four runs without significant loss in catalytic activity. [ABSTRACT FROM AUTHOR]

A robust, safe and magnetically recoverable palladium catalyst was synthesized by anchoring Pd(II) onto ethylenediaminetetraacetic acid-coated Fe3O4 (Fe3O4@EDTA) magnetic nanoparticles. The Fe3O4 magnetic nanoparticle-supported Pd(II)-EDTA complex catalyst thus obtained was characterized using scanning and transmission electron microscopies, thermogravimetric analysis, vibrating sample magnetometry, X-ray diffraction, and atomic emission and Fourier transform infrared spectroscopies. Fe3O4@EDTA-Pd(II) was screened for the and in water. The Pd content of the catalyst was measured to be 0.28 mmol Pd g−1. In addition, the Fe3O4@EDTA-Pd catalyst can be easily separated and recovered with an external permanent magnet. The anchored solid catalyst can be recycled efficiently and reused five times with only a very slight loss of . Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Mesoporous silica-coated magnetic were prepared; their surface , followed by reaction with CuI, were carried out to develop a Cu-grafted functionalized mesoporous material. This system is able to catalyze oxidative of aromatic aldehydes with amine hydrochloride salts, generating amide derivatives in moderate to good yields. Magnetic properties of this catalyst led to easy separation as well as providing significant recyclability. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Immobilization of copper(I) ions on magnetic nanoparticles was performed using surface modification of Fe3O4 with creatine. Fe3O4@creatine‐Cu(I) magnetic catalyst was synthesized and applied in C&bond;X cross‐coupling reactions with aryl halides in a deep eutectic as a green solvent. The results indicate the Fe3O4@creatine‐Cu(I) magnetic nanoparticles showed excellent activity and high stability. In addition, it was revealed that this catalyst can be recycled five times without significant loss in catalytic activity. [ABSTRACT FROM AUTHOR]

Magnetic Fe(OH)3@Fe3O4 nanoparticles were successfully prepared and characterized. This magnetic nanocomposite was employed as an efficient, reusable, and environmentally benign heterogeneous catalyst for the direct amidation of alcohols with amine hydrochloride salts. Several derivatives of primary, secondary and tertiary amides were synthesized in moderate to good yields in the presence of this catalytic system. The catalyst was successfully recycled and reused up to sue times without significant loss of its catalytic activity. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles coated with silica was modified with acetylacetone (acac) followed by copper chloride. After characterization using some different microscopic and spectroscopic techniques such as XRD, FT-IR, VSM, SEM–EDX, TEM, TGA, and ICP, its catalytic activity was investigated in the oxidative coupling of carboxylic acids with N , N -dialkylformamides for the preparation of amides. Different derivatives of tertiary amides were synthesized in moderate to good yields in the presence of just 0.46 mol% of this catalytic system. Magnetic properties of this nano-catalyst led to its easy separation as well as reusability. [ABSTRACT FROM AUTHOR]

Abstract: Superparamagnetic nanoparticles of modified sulfuric acid (γ-Fe2O3@SiO2-OSO3H) represent a straightforward and green catalyst for the rapid synthesis of aminoimidazopyridine skeletons via the Ugi-like Groebke-Blackburn-Bienaymé three-component reaction. The γ-Fe2O3@SiO2-OSO3H catalyst could be recovered and reused in five reaction cycles, giving a total TON=453. The products were prepared under solvent-free conditions without any additives. [Copyright &y& Elsevier]

Abstract: A highly efficient magnetically recoverable nano-catalyst was fabricated. The material synthesized has been fully characterized by vibrating sample magnetometry (VSM), X-ray powder diffraction, scanning and transmission electron microscopy, FT-IR, and the Brunauer-Emmett–Teller (BET) isotherm method. An investigation of its catalytic activity showed it to be a unique heterogeneous Lewis acid catalyst for the synthesis of α-hydroxy and α-aminophosphonates, giving a total turnover number ⩾450 for five consecutive runs. The catalyst is superparamagnetic having a ‘magnetization (left behind after an external magnetic field is removed)’ to ‘magnetic saturation’ ratio of about 0.0008, and thus could be easily separated by the use of an external magnetic field and was not agglomerated by exposure to magnetic fields. [Copyright &y& Elsevier]