Journal of Applied Chemical Research
Volume:10 Issue: 2, Spring 2016

An efficient synthesis of 1,3-thiazole drivatives is described via a three component reaction isothiocyanates, tetramethyl thiourea and ethyl bromopyruvate.

Iron (III) meso-tetrakis(p-sulfonatophenyl)-β-octabromoporphyrin supported on Amberlite IRA- 400 [Fe(Br8TPPS)-Ad-400] is a robust and efficient catalyst for oxidation of alkenes and alcohols at room temperature. The catalyst exhibits a high activity and stability in hydrocarbon oxidation by H2O2. The method was useful in the oxidation of various primary, secondary-aliphatic, alicyclic and aromatic alcohols. Both activated and non-activated alcohols were converted into their corresponding carbonyls efficiently and selectively. Aqueous hydrogen peroxide as an environmentally benign oxidant is utilized in oxygen transfer. The oxidation reaction using heterogeneous solid catalysts with H2O2 as oxidants are environmentally friendly routes to produce extensively useful epoxides which are traditionally obtained from capital-intensive or environmentally polluted processes.

Phenolic compounds are considered as priority pollutants because of their high toxicity at low concentration. In the present study, the sorption of p-chlorophenol (p-CP) by dried activated sludge was investigated. Activated sludge was collected as slurry from the sludge return line of a municipal wastewater treatment plant. Sorption experiments were carried out in batch mode. In order to investigate the effect of operating parameters on the removal efficiency of p-CP, four independent variables, including pH, initial concentration of p-CP, contact time and adsorbent dosage were studied. Artificial neural network (ANN) and response surface methodology (RSM) were developed for modeling of biosorption process. Results indicated that, Dried activated sludge can efficiently remove p-chlorophenol from aqueous solutions. The RSM method suggested that pH is the most significant parameter for biosorption process. Finally, RSM technique gave a function and neural network gave a structure for prediction. Neural network have a higher degree of accuracy and ANN predicted outputs were closer to the actual outputs of experiments in comparison with RSM technique.

In this paper, Fe3O4@SiO2 core/shell magnetic nanostructure has been synthesized and modified by N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (AEAPTMS). Fe3O4@SiO2 was used as a novel adsorbent for separation of hexachloroplatinic acid. X-ray diffraction (XRD), scanning electron microscopy (SEM), and FT-IR technique were used to characterize morphologies and surface texturing of these adsorbents. The effective factors on adsorption, such as pH, contact time; salt effect and temperature were studied systematically. The optimal conditions of Platinum adsorption were obtained at temperature of about 25oC, pH about 2.5 and the equilibrium time of 30-40 minutes. The maximum adsorption capacity (qmax) in the optimal conditions was equal to 74 mg/g. The magnetic separation of the absorbent was achieved by a magnet and finally the absorbent was compared with other absorbents. Inductive coupled plasma optical emission spectrometer (ICP-OES) was used for determination of metal ion concentrations in the aqueous solution.

Simple three-component reactions between dialkyl acetylenedicarboxylate, primary amines and isothiocyanates in the presence of catalytic amount of ZnO nanorods are investigated in water at room temperature which produced thiazole derivatives in good yields.

A SO3H-containing solid acid namely SO3H-functionalized phthalimide (SFP) was synthesized from phthalimide and chlorosulfonic acid, and identified by studying its FT-IR, 1H and 13C NMR, Mass, XRD, TG and DTG spectra. Afterward, its catalytic activity was examined for the solvent-free condensation of dimedone (5,5-dimethyl-1,3-cyclohexanedione) (2 eq.) with arylaldehydes (1 eq.). The results showed that SFP is a highly efficient catalyst to promote the title reaction for the preparation of 9-aryl-1,8-dioxo-octahydroxanthenes.

Electron-rich aza-aromatic compounds such as indoles is structures of particular interest and importancein organic chemistry. A useful procedure for the preparation of new 3-sulfenyl indole derivatives using S-alkyl or S-arylthiophthalimides as sulfenylating agents and poly(N, N′-dibromo-N-ethyl-naphthyl-2,7-disulfonamide) as novel catalyst is described. The method represents an efficient preparation ofsulfenyl aza-aromatics, which are useful intermediates forimportant organic transformations, due to the great importanceof functionalized indoles among natural compoundsand pharmaceutical products.3-Arylthioindole apply as a block of compounds for the treatment of diseases. The direct 3-arylthiolation of 2-substituted indoles using poly(N, N′-dibromo-N-ethyl-naphthyl-2,7-disulfonamide) in CH2Cl2 with a wide variety of indole deraivatives has been accomplished.This method is effective even with 2 unsubstituted indoles.Simple methodology, easy workup procedure, regioselectivity and reusability of the catalyst are some advantages of this work.The reaction occurred under mild conditions,and the products were obtained in goodyields. The catalyst was recovered after completion of the reaction and re-used with minimum loss of activity over five cycles.

Magnetic Fe3O4 nanoparticles modified by polypyrrole (PPy@Fe3O4 MNPs) was synthesized by chemical co-precipitation method and used as an adsorbent for removal of cationic dyes, Reactive Red195, from aqueous solutions. The resulting products are characterized by scanning electron microscope (SEM) and FT-IR. The effects of solution pH value, adsorbent amount, adsorption time and capacity of the nanocomposites have been fully investigated. The particles were showed to capture 99.0 mg g-1 of the dye within less than 10 min of contact time. Also, the sorption of Reactive Red195 dye was pH dependent and the higher efficiency of dye concentration removal was at pH 3.0. Experiments were carried out to investigate adsorption kinetics, adsorption isotherms and adsorption capacity. Kinetic data were well fitted by a pseudo second-order model. In the aqueous solution of Reactive Red195 dye at 25 °C, the adsorption data could be fitted by the Langmuir equation with a maximum adsorption amount of 99.0 mg g-1. Moreover, the MNPs were recovered with over than 94% efficiency using methanol as elution agent.

In this investigation, new structures based on homoisoflavonoids were designed. Homoisoflavonoids are considered as an important class of flavonoids with various biological properties such as cytotoxicity. A new series of benzylidene-6,7-dihydro-8H-[1,3]dioxolo 4,5-g] chromen-8-one derivatives were developed and their cytotoxic activities evaluated for all compounds on three human breast cancer cell lines. Benzo[d][1,3]dioxol-5-ol was chosen as a substrate and reacted with 3-bromopropanoic acid to form an intermediate which turns to 6,7-dihydro-8H-[1,3]dioxolo[4,5-g]chromen-8-one after Feridel-Crafts reaction with oxalyl chloride. In the end, title compounds were produced by aldol condensation of later compound under acidic condition with aromatic aldehydes in moderate yields. Eight novel derivatives were tested for their activities against all human breast cancer cell lines including MCF- 7, T47-D and MDA-MB-231 using MTT assay. After all tests on synthesized products, we can reach to this point that (E)-7-(3-bromo-4,5-dimethoxybenzylidene)-6,7-dihydro-8H- 1,3] dioxolo[4,5-g]chromen-8-one 4a presents the highest cytotoxicity in all three cell lines as a result of its shorter aliphatic tail in benzylidene moiety.

This paper describes the aging behavior of the oil impregnated repulped cellulose and compares it with the aging behavior of the oil impregnated standard cellulose. In order to evaluate the reliability of using repulped cellulose in transformers, the accelerated aging process was applied to both types of cellulose by increasing the temperature to 150 °C and their aging behavior was studied and compared through measuring their viscometric degree of polymerization (DP) in consecutive aging periods. Results were fitted to estimate an aging relation respect to the initial DP and this was yield that the accelerated pyrolysis behavior of two survived types of cellulose are completely similar and obeys the same damping model. From the obtained results, it can be concluded that the moulded insulating parts made of repulped cellulose can be used in the insulation system of power transformers with a good and acceptable reliability. The reduction of DP to 30% of its initial value was estimated as a criterion for the end of life time of these celluloses.

In this research, the efficiency of electrocoagulation treatment process using iron and aluminum electrodes to treat synthetic wastewater containing Reactive Red 24 (RR 24) was studied. The effects of parameters such as current density, pH, type of electrolyte, initial dye concentration, electrolyte concentration, temperature, and inter electrode distance on dye removal efficiency were investigated. The results showed that dye and chemical oxygen demand removals were 99.6% and 91.5% by using iron and were 97.9% and 83.8%, by using aluminum electrodes. The removal of dye exhibited pseudo first order with good correlation coefficients (0.955 and 0.990 for Fe and Al electrodes respectively. It can be concluded that electrocoagulation process by Iron electrode is very efficient and clean process for reactive dye removal from colored wastewater.

Synthesis of enantiomerically pure isoxazolidine via an asymmetric 1,3- dipolar cycloaddition reaction of nitrone with electron-deficient dipolarophile was described. The process occurs at room temperature in aqueous ethanol as a green solvent and in the presence of a bidendate bis(imine)–Cu(II)triflate complex as catalyst. The reaction mechanism is discussed on the basis of the assignment of the absolute configuration of the cycloadducts.