Silica Boron Sulfonic Acid as a New and Efficient Catalyst for the Green Synthesis of Quinoxaline Derivatives at Room Temperature | Author : Sami Sajjadifar | Abstract | Full Text | Abstract :A simple, highly efficient and green procedure for the condensation of aryl and alkyl 1,2-diamines with a-diketones in the presence of catalytic amount of silica boron sulfonic acid (SBSA) at room temperature is described. By Using this method, quinoxaline derivatives as biologically interesting compounds are produced in high to excellent yields and short reaction times. |
| Epoxidation of norbornene in the presence of Oxidizing agents | Author : Hadi Jabbari | Abstract | Full Text | Abstract :Part1: epoxidation of norbornen and norbornadien in the presence of dimethyloxirane as reagent oxidant has been investigated.
Part 2: A general procedure for the epoxidation of norbornen using hydrogen peroxide as the oxidant in the presence of ruthenium trichloride has been investigated. norbornene gave the epoxides at room temperature in good to excellent yield. And epoxy norbornene identified by H-NMR,FT-IR,13C-NMR method spectroscopics.
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| Synthesis and Characterization of Novel Composite-Based Phthalocyanine Used as Efficient Photocatalyst for the Degradation of Methyl Orange | Author : Hossein Salavati; Abbas Teimouri; Shahnaz Kazemi | Abstract | Full Text | Abstract :In this study, Copper-tetraaminophthalocyanine (CuTAP) supported on polyvinylcholoride by reflux condition was synthesized and characterized using Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Scanning electron microscopy (SEM) and UV-vis spectroscopy. The results showed that the photocatalytic degradation of methyl orange was performed in mild conditions at ambient pressure and temperature under visible light. The synthesized catalyst could be readily separated from the catalytic system by centrifuging and loss of activity was negligible when the catalyst was recovered in four consecutive cycles. The effect of operational various factors such as catalyst amount, initial dye concentration and contact time on degradation of methyl orange were investigated. Optimization results showed that maximum degradation of methyl orange efficiency 98.6 % was achieved at the optimum conditions. |
| Molecular Structure, NMR, FMO, MEP and NBO Analysis of ethyl-(Z)-3-phenyl-2-(5-phenyl-2H-1,2,3,4-tetraazol-2-yl)-2-propenoate Based on HF and DFT Calculations | Author : Ali Ramazani; Masoome Sheikhi; Hooriye Yahyaei | Abstract | Full Text | Abstract :In the present work, for the first time the quantum calculations of Ethyl-(Z)-3-phenyl-2-(5-phenyl-2H-1,2,3,4-tetraazol-2-yl)-2-propenoate are evaluated using the HF and B3LYP methods with 6-311++G** basis set. The geometry of the title compound was optimized by B3LYP/6-311++G** level of theory. The theoretical 1H and 13C NMR chemical shift values of the title compound are calculated and compared with the experimental results. The computed data are in good agreement with the experimental data. Frontier molecular orbitals (FMOs), molecular electrostatic potential (MEP), energy gap between HOMO and LUMO, electronic properties, thermodynamic parameters, natural charges distribution (NBO charges) and NBO analysis were investigated by theoretical calculations.
In the present work, for the first time the quantum calculations of Ethyl-(Z)-3-phenyl-2-(5-phenyl-2H-1,2,3,4-tetraazol-2-yl)-2-propenoate are evaluated using the HF and B3LYP methods with 6-311++G** basis set. The geometry of the title compound was optimized by B3LYP/6-311++G** level of theory. The theoretical 1H and 13C NMR chemical shift values of the title compound are calculated and compared with the experimental results. The computed data are in good agreement with the experimental data. Frontier molecular orbitals (FMOs), molecular electrostatic potential (MEP), energy gap between HOMO and LUMO, electronic properties, thermodynamic parameters, natural charges distribution (NBO charges) and NBO analysis were investigated by theoretical calculations. |
| Central composite design optimization of methylene blue scavenger using modified graphene oxide based polymer | Author : Mehrnaz Alem; Abbas Teimouri; Hossein Salavati; Shahnaz Kazemi | Abstract | Full Text | Abstract :This research reports the synthesis, characterization and catalytic properties of novel supported catalyst based on nickel acetate hydrate (denoted as NiOAC) immobilized on graphene oxide (denoted as GO) modified polyethylene glycol (abbreviated as PEG). The supported catalyst was characterized by X-ray diffraction spectroscopy (XRD), Scanning electron microscopy (FESEM), Furrier transforms infrared spectroscopy (FT-IR) and diffuse reluctance spectroscopy (DRS). In addition, under mild reaction conditions, the mentioned catalyst exhibited high photocatalytic activity and reusability in photocatalytic degradation of dyes as pollutants. For this research, a statistical method called Response Surface Methodology (RSM) has been used to economize the number of experiments and their meaningful interpretation. The effect of various factors such as catalyst amount, time, pH on degradation of methylene blue were investigated. Optimization results for 20 ppm methylene blue showed that maximum degradation efficiency 92.9% was achieved at the optimum conditions: catalyst amount 24.6 mg, pH= 7.6 and time 23.3 min. |
| An insight on kinetic adsorption of Congo red dye from aqueous solution using magnetic chitosan based composites as adsorbent | Author : Nahid Rasouli; Hossein Salavati; Maryam Movahedi; Ali Rezaei | Abstract | Full Text | Abstract :In the present research, a series of magnetic chitosan based composites with the general formula of NixMn1-xFe2O4/CS were synthesized from spinel type transition metal ferrites [NixMn1-xFe2O4 (where x= 0, 0.2, 0.5 and 1.0)] and chitosan (CS) as a polymer. The structure and composition of the synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The adsorption activity of the synthesized magnetic chitosan based composites was evaluated at different contact time, initial dye concentration and temperature for the removal of Congo red (CR) dye from aqueous solution. Furthermore, the influence of the Mn content on adsorption capacity of the synthesized magnetic chitosan based composites were studied. The results of adsorption kinetic of CR dye using spinel type transition metals NixMn1-xFe2O4 and NixMn1-xFe2O4/CS followed pseudo second-order model. The experimental results showed that high percentage of CR dye removal was observed by Ni0.5Mn0.5Fe2O4/CS sample after 180 min. The adsorption performance shows that the chitosan based composites can be more efficient than spinel type transition metals for removal of CR dye. Moreover, the magnetic chitosan based composites can be quickly separated from the aqueous solution by an external magnet after adsorption process. |
| Determination of Cu, Co, and Pb in selected frozen fish tissues collected from Benghazi markets in Libya | Author : Nabil R Bader | Abstract | Full Text | Abstract :The concentrations of some heavy metals (Cu, Co, and Pb) were investigated in muscle, liver and gills of three fish species (Mullus surmuletus, Seriola dumerili, and Sparus aurata) collected from frozen fish markets in Benghazi city, Libya, during winter 2016, using flame atomic absorption spectrometry (FAAS). The mean concentrations (µg/g) of the heavy metals in fish tissues ranged as follows: Cu (44.80 – 79.33), Co (198.66 – 238.26), Pb (56 – 192). The highest mean concentration, 238.26µg/g was recorded for Co in the muscle of Mullus surmuletus, on the other, the lowest mean concentration, 44.80 µg/g, was recorded for Cu in gills of Mullus surmuletus. The concentrations for Cu and Pb in all fish samples were over the Effect Range-Low (ERL) but were under the Effect Range-Median (ERM) in metal pollution index (MPI). The concentrations of (Cu, Co and Pb) were higher than the maximum permissible limits specified by some food regulatory bodies like WHO. The results indicate that heavy consumption of frozen fishes in Benghazi city markets may pose a health risk to the consumers. |
| An Efficient Method for Chemoselective Acetylation of Activated Alcohols Using Nano ZnFe2O4 as Catalyst | Author : Zubaidha Pudukulathan; Ummae Shaikh; Qudsiya Y Tamboli; S M Pathange; Zeyad Dahan | Abstract | Full Text | Abstract :The spinels of AB2O4 type display very interesting catalytic properties and have been shown to possess potential industrial applications . Especially spinels have been shown to be selective and active catalysts . Nano ZnFe2O4 ferrite synthesized by sol–gel auto-combustion method was found to be an efficient catalyst for acetylation of activated alcohols using acetic acid as reagent. A variety of activated alcohols undergo acetylation under the reaction conditions to afford the corresponding acetates in good yield. The salient features of this protocol include selectivity towards activated alcohols, use of cheap catalyst and environmentally benign protocol. The chemoselectivity of the protocol for activated systems making amines, phenols and other nucleophiles inert to the present reaction conditions makes this approach synthetically attractive and would supplement the many other protocols that are available. |
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