Journal of Applied Research in Chemistry
Year:2010 | Volume:4 | Issue:14|Papers Count:20

Simple and improved conditions have been found to carry out the Biginelli reaction for the synthesis of 3, 4-dihydropyrimidin-2 (1H) - one derivatives. This synthesis was performed in the presence of 12-molybdophosphoric acid (H3PMo12O40) as catalyst. These reactions were performed under solvent free conditions with microwave irradiation as the energy source. Compared with the classical Biginelli reaction conditions, this new method has the advantage of excellent yields (76–96%). The advantages of this novel protocol include the excellent yield, operational simplicity, short time, and the avoidance of the use of organic solvents and friendly preparation. Products were identified using physical and spectroscopic data.

In this study, iodide salts and carbonyl complexes of specific metals used as promoters in carbonylation of methanol in iridium/iodide based catalyst. The iridium catalyzed carbonylation of methanol to acetic acid is promoted by two distinct classes of promoters; simple iodide salts of zinc, cadmium, mercury, indium and gallium and carbonyl or halocarbonyl complexes of tungsten, rhenium, osmium and ruthenium. All of these promoters are led to increase the rate of methanol carbonylation. In this experimental research, it has been observed that the effect of ruthenium promoter in rate of methanol carbonylation and high reaction rate is achieved by increasing the ruthenium concentration. The experimental tests are carried out to identify the effect of different promoters. In the presence of ruthenium and iridium, it has been observed that the maximum activity is achieved between 5 to 6 weight percent of water concentration.

In this study, organically modified nanoclay (organoclay) prepared by exchanging of the hexadecyltrimethylammonium bromide (HDTMA) with sodium ions in montmorillonite structure was tested for petroleum hydrocarbon adsorption. The effectiveness of the sorbent materials for sorption of a range of products that are likely to be involved in oily wastewaters and land-based oil spills was investigated using crude oil, kerosene, gasoline and toluene. The process parameters such as sorbent dosage and contact time were reported. Results showed that adsorption capacity of the organoclay was clearly higher than of the unmodified clay. The obtained results in a batch wise process also showed that depending on the hydrocarbons the adsorption capacity was in the range of 4 to 10 gram per gram of adsorbent. Also adsorption equilibrium was attained within 1 h.

This paper describes an investigation into usefulness of some instrumental methods (GLC and UV Spectroscopy) in the detection of adulteration of Olive oil with Olive-Pomace oil (it is relatively cheap oil mixed as adulterants with olive oil) in the admixture of Virgin Olive oil and Canola oil (0 up to 30% Virgin Olive Oil). It was observed that 5% Pomace is detectable with sterol separation using GLC analysis. Erythrodiol and Uvaol is two compounds which are recognized in admixture containing Pomace oil. The limit of detection (LOD) and limit of quantification (LOQ) of GLC method are 0.09% and 0.3% respectively. There is good correlation between UV absorption coefficient (K270) and extent of Pomace oil in admixture (r=0.9721).

3-arylhydrazono-2, 4-dioxo-4-phenylbutanoates has been prepared by the coupling of benzoyl pyruvic ester with aryldiazonium chlorides.3-Arylhydrazono-2, 4-dioxo-4-phenylbutanoates reacts with 1, 2-phenylenediamine, 2-aminophenol, and 2-aminothiophenol, to form the corresponding quinoxaline, 1, 4-benzoxazine, and 1, 4-benzothiazine derivatives. Interaction of 3-arylhydrazono-2, 4-dioxo-4-phenylbutanoates with 2, 3-diaminopyridine, 1, 2-ethelenediamine, and 1, 2-diaminohexane results in pyrazine products The structure of the resulted products were confirmed by determination of the melting point and spectrophotometric techniques such as IR and 1H NMR and in some cases by using 13C-NMR spectroscopy.

Nitrophenols 2a-j were synthesized in moderate to high yields via nitration of phenols by antimony nitrate, Sb (NO3) 3.5H2O, as an efficient nitrating reagent. The reactions were carried out at room temperature by grinding equimolar amounts of phenol compound and Sb (NO3) 3.5H2O in an ice-water bath.

Cadmium oxide film is synthesized via solvothermal method which benefits from simple low temperature technique. A uniform and crack free film of CdO is coated on a glass substrate. The synthesized film is annealed at 350° C for 1 hour in order to produce pure phase of CdO with good adherence. Films are characterized by X-ray diffraction, scanning electron microscopy (SEM), thermogravimetric (TGA) - differential thermal (DTA) analysis, Fourier Transform Infrared (FT-IR) and Photoluminesence (PL) spectroscopy. Grain size of the annealed film is proved to be about 30-100 nm. Band gap was also calculated using UV-Visible spectroscopy.

The heteronuclear [Hg (SCN) 3Cu (en) 2] NO3 complex (en=1, 2-ethandiamine (en) and 1, 10-phenanthroline (phen)), has been synthesized by reaction of HgCl2, KSCN, en and Cu (NO3) 2.3H2O in molar ratios of 1: 4: 2: 1. [Hg (SCN) 3Ni (en) 2] Cl complex, has been prepared by reaction of HgCl2, KSCN, en and NiCl2.6H2O in molar ratios of 1: 4: 2: 1. The synthesized complexes have been characterized by FT-IR spectroscopy, elemental analysis (CHN) and thermo gravimetric analysis (TGA). The UV-Vis spectra and luminescent properties of these complexes have also been investigated.

Much research is currently focused on the use of starch as an industrial raw material, which can reduce dependence on non-renewable resources. Pure starches of plants includes 20 -30% of amylose, this value might become to 80% in some starches scarcely, 70-90% amylopectin, approximately 1% fat, protein and minerals. Starches from various sources contain different amounts of amylose and amylopectin, which influence physicochemical properties such as gelatinization, water absorption and paste viscosity. Therefore, amylose/amylopectin (Am/Ap) ratio in starch would effect on physico-mechanical properties of the material which produced from it. The determination of Am/Ap ratio in several samples of starch by a simple modified method was described in this paper and the samples with different Am/Ap ratio were applied as filler in rubber compounds. The physico-mechanical properties of obtaind cure rubbers were investigated. The results showed that the physico-mechanical properties of Natural rubber (NR) compounds filled by various starches are mainly correlated with Am/Ap ratio in the starch samples.

A spectrophotometric method for simultaneous analysis of triamterene and hydrochlorothiazide is proposed by application of continuous wavelet transform on the spectral data without time-consuming extraction step.Different wavelets families were tested and Coiflets wavelet family (coif1) and Reverse birothogonal wavelets family (rbio 2.8) were selected and applied under the optimal conditions for simultaneous analysis.The validation of the developed methods was confirmed by analyzing various synthetic mixtures of the investigated drugs.Triamterene and hydrochlorothiazide could be determined simultaneously in the range of 0.75-5.0 mg ml-1 and 1.0– 6.0 mg. ml-1 respectively and LOD for triamterene and hydrochlorothiazide was less than 1.07 mg. ml-1 and 0.89 mg. ml-1 respectively.The experimental results obtained from the continuous wavelet transform approach were statistically compared with those obtained by derivative spectrophotometry and successful results were reported.