Iron(III) phosphate catalyzed synthesis of 1,4-dihydropyridines

Novel 1,4-dihydropyridines (1,4-DHPs) are prepared efficiently via Hantzsch reaction using aldehydes, benzylacetoacetate and catalytic amount of iron(III) phosphate under solvent-free conditions in good yields.     

Biosynthesis of Nano Nickel Oxide Powder Using Malva sylvestris; Evaluation of Electrocatalytic Activity for Determination of Cephalexin in Real Samples

Russian Journal of Electrochemistry - In the present study, Malva sylvestris leaf extracts was used as a reducing agent for the synthesis of NiO NPs. They were characterized by FT-IR, XRD, and SEM...     

Preparation of poly(naphthylamine-formaldehyde); Application as a new and an effective inhibitor of steel in hydrochloride acid solution

In this research, we first prepared poly (naphthylamine-formaldehyde) (PNAF) and then investigated its corrosion inhibition properties for polished steel specimens in 1 M HCl solution using chemical and electrochemical methods. Results showed that the PNAF could serve as an effective inhibitor of the corrosion of steel in hydrochloric acid media (the inhibition efficiency of this polymer at an optimum concentration of 100 mg L^–1 was 99.9 %). The effect of temperatures on the corrosion behavior of steel was studied in the temperature ranging from 303 to 333 K for 1 M HCl at an optimum concentration of PNAF. It has been demonstrated that the adsorption behavior of this polymer on steel in 1 M HCl was found to obey Langmuir adsorption isotherm. Also, potentiodynamic polarization measurements showed that PNAF was a mixed type inhibitor.     

Facile preparation of highly stable and active hybrid palladium nanoparticles: effectual,reusable and heterogeneous catalyst for coupling reactions

Palladium nanoparticles were supported on a bed of Fe₃O₄@‐NH₂@Murexide using a simple and efficient method, and characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, scanning and transmission electron microscopies and inductively coupled plasma optical emission spectrometry. The catalytic system showed great efficiency in cross‐coupling reaction of aryl iodides and arylboronic acid and in Sonogashira cross‐coupling reaction in the green solvent EtOH–H₂O (1:1). The isolation and recovery of the catalyst were simple and facile and it could be used for several successive Suzuki–Miyaura coupling and Sonogashira cross‐coupling reactions. Copyright © 2016 John Wiley & Sons, Ltd.     

Palladium immobilized on amidoxime‐functionalized magnetic Fe3O4 nanoparticles: a highly stable and efficient magnetically recoverable nanocatalyst for sonogashira coupling reaction

We describe the synthesis of a novel Fe₃O₄/amidoxime (AO)/Pd nanocatalyst by grafting of AO groups on Fe₃O₄ nanoparticles and subsequent deposition of Pd nanoparticles. Prior to grafting of AO, the 2‐cyanoethyl‐functionalized Fe₃O₄ nanoparticles prepared through combining 2‐cyanoethyltriethoxysilane and Fe₃O₄ were treated with hydroxylamine. The AO‐grafted Fe₃O₄ nanoparticles were then used as a platform for the deposition of Pd nanoparticles. The catalyst was characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, scanning and transmission electron microscopies, vibrating sample magnetometry, wavelength‐ and energy‐dispersive X‐ray spectroscopies and inductively coupled plasma analysis. Fe₃O₄/AO/Pd is novel phosphine‐free recyclable heterogeneous catalyst for Sonogashira reactions. Interestingly, the novel catalyst could be recovered in a facile manner from the reaction mixture by applying an external magnet device and recycled seven times without any significant loss in activity. Copyright © 2015 John Wiley & Sons, Ltd.     

Cobalt manganese oxide nanoparticles as recyclable catalyst for efficient synthesis of 2‐aryl‐1‐arylmethyl‐1H‐1,3‐benzimidazoles under solvent‐free conditions

Cobalt manganese oxide nanocatalyst was synthesized and it was found that it is a highly efficient green catalyst for the synthesis of 2‐aryl‐1‐arylmethyl‐1H‐1,3‐benzimidazoles under solvent‐free conditions. The marked advantages of this method are the simple experimental procedures, shorter reaction times, high yields of product, reusable and non‐toxic catalyst and solvent‐free conditions. Copyright © 2015 John Wiley & Sons, Ltd.     

A highly stable and efficient magnetically recoverable and reusable Pd nanocatalyst in aqueous media heterogeneously catalysed Suzuki C–C cross‐coupling reactions

Surface modification of Fe₃O₄ nanoparticles with triethoxyethylcyanide groups was used for the immobilization of palladium nanoparticles to produce Fe₃O₄/Ethyl‐CN/Pd. The catalyst was characterized using Fourier transform infrared, wavelength‐dispersive X‐ray, energy‐dispersive X‐ray and X‐ray photoelectron spectroscopies, field‐emission scanning electron and transmission electron microscopies, and X‐ray diffraction, vibrating sample magnetometry and inductively coupled plasma analyses. In this fabrication, cyano groups played an important role as a capping agent. The catalytic behaviour of Fe₃O₄/Ethyl‐CN/Pd nanoparticles was measured in the Suzuki cross‐coupling reaction of various aryl halides (Ar? I, Ar? Br, Ar? Cl) with phenylboronic acid in aqueous phase at room temperature. Interestingly, the novel catalyst could be recovered in a facile manner from the reaction mixture by applying an external magnet device and recycled seven times without any significant loss in activity. Copyright © 2015 John Wiley & Sons, Ltd.