Nanochemistry
Hassan Karami; Mohammad Ali karimi; Ehsan Atin
Volume 4, Issue 4, pp. 359-490, Serial No. 13 , October 2016, , Pages 449-465
Abstract
This paper presents a new gel combustion method to synthesize palladium nanoparticles, palladium oxide (PdO) nanoparticles and palladium-palladium oxide nanocomposites. In the proposed method, there are some effective parameters including palladium chloride concentration, polyvinyl alcohol (PVA) concentration, ...
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This paper presents a new gel combustion method to synthesize palladium nanoparticles, palladium oxide (PdO) nanoparticles and palladium-palladium oxide nanocomposites. In the proposed method, there are some effective parameters including palladium chloride concentration, polyvinyl alcohol (PVA) concentration, acid concentration, solvent composition and combustion temperature that their values are investigated and optimized by the "one at a time" method. The experimental data shows that the combustion temperature is the main factor that controls the sample composition to obtain palladium, palladium oxide or palladium-palladium nanocomposites. Characterization of the synthesized samples is performed by SEM, TEM, XRD and BET specific surface area measurements. The optimized sample consisted of clusters; each cluster is composed of smaller nanoparticles with an average diameter of 25 mm and 10 m2. g-1 specific surface areas. The optimized Pd-PdO nanocomposite is successfully used as nanocatalyst for the hydrogen revolution.
Organic chemistry
Mehdi Forouzani; Navabeh Nami; Hassan Ghasemnejad-Bosra; Omid Khalilpour Tylami
Volume 3, Issue 3, pp. 180-282,Serial No. 8 , July 2015, , Pages 232-243
Abstract
One-pot reaction of aldehydes or ketons with aniline derivatives was performed using NaBH4 and Fe3O4 magnetic nanoparticles (MNPs). The optimum amount of Fe3O4 MNPs was 5 mol% under solvent free condition. The corresponding products were obtained in good to excellent yields. The magnetically recoverable ...
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One-pot reaction of aldehydes or ketons with aniline derivatives was performed using NaBH4 and Fe3O4 magnetic nanoparticles (MNPs). The optimum amount of Fe3O4 MNPs was 5 mol% under solvent free condition. The corresponding products were obtained in good to excellent yields. The magnetically recoverable iron oxide nanoparticles are found to be efficient for synthesis of amine derivatives. These nanoparticles are effective in green chemistry and could be successfully reuse. in addition to having the general advantages attributed to the inherent magnetic property of nanocatalyst, Fe3O4MNPs exhibited exceptionally high catalytic activity compared to other catalysts, to yield the desired products in short reaction time and mild reaction conditions.
Organic chemistry
Faraidon Ghaderi; Saadi Saaidpour
Volume 4, Issue 4, pp. 359-490, Serial No. 13 , October 2016, , Pages 466-475
Abstract
The quantitative structure–property relationship (QSPR) method is used to develop the correlation between structures of crude oil hydrocarbons (80 compounds) and their boiling point and water solubility. Sub-structural molecular fragments (SMF) calculated from structure alone were used to represent ...
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The quantitative structure–property relationship (QSPR) method is used to develop the correlation between structures of crude oil hydrocarbons (80 compounds) and their boiling point and water solubility. Sub-structural molecular fragments (SMF) calculated from structure alone were used to represent molecular structures. A subset of the calculated fragments selected using stepwise regression (forward and backward steps) (SR) was used in the QSPR model development. Multiple linear regressions (MLR) are utilized to construct the linear prediction model. The prediction results agrees well with the experimental values of these properties. The comparison results indicate the superiority of the presented models and reveal that it can be effectively used to predict the boiling point temperatures and water solubility values of crude oil hydrocarbons from the molecular structures alone. The stability and predictivity of the proposed models were validated using internal validation (leave one out and leave many out) and external validation. Application of the developed models to test set of 16 compounds demonstrates that the new models are reliable with good predictive accuracy and simple formulation.
Organic chemistry
Hadi Jabbari; Jabbar Khalafy; Peyman Najafi Moghadam
Volume 3, Issue 3, pp. 180-282,Serial No. 8 , July 2015, , Pages 244-253
Abstract
A most effective and less energy demanding method of producing fatty esters, diol esters, by esterifying fatty acids, with neopentyl and ethylenglycol alcohols in the presence of an acidic ion exchange resin catalyst(polyestyrendivinylbenzensulfated) was investigated at elevated temperature. In this ...
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A most effective and less energy demanding method of producing fatty esters, diol esters, by esterifying fatty acids, with neopentyl and ethylenglycol alcohols in the presence of an acidic ion exchange resin catalyst(polyestyrendivinylbenzensulfated) was investigated at elevated temperature. In this process an azeotroping agent, toluene, was used to facilitate continuous removal of water by distillation, formed as a by-product during the esterification reaction.The esterification reaction is completed within 4-5 hours and neopentyl and ethylenglycol esters produced with properties of lubricity and biodegradability One of the most important modifications of the carboxyl group of the fatty acid chain is the esterification of the fatty acids obtained by cleavage of such esters. Those processes are performed on large scale. Esterification reactions of neopentylpolyols are normally catalysed with acidic or basic catalysts.Typical homogeneous catalysts are p-toluene sulphonic acid, phosphoric acid, sulphuric acid, sodium hydroxide, sodium ethoxide and sodium methoxide[1-5]. In some cases, heterogeneous catalysts such as Sn-oxalate or cation exchange resins are used. Enzyme catalysed reactions are also known
Nanochemistry
Alireza Khorshidi; Shahab Shariati; Masoumeh Aboutalebi; Neda Mardazad
Volume 4, Issue 4, pp. 359-490, Serial No. 13 , October 2016, , Pages 476-482
Abstract
Fe3O4 magnetic nanoparticles were synthesized by co-precipitation of Fe2+ and Fe3+ in aqueous NaOH. Then silica was coated on the obtained nanoparticles and the whole composite was functionalized with chlorosulfonic acid in CH2Cl2. The obtained nanocomposite (Fe3O4@SiO2-SO3H) was characterized by FT-IR, ...
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Fe3O4 magnetic nanoparticles were synthesized by co-precipitation of Fe2+ and Fe3+ in aqueous NaOH. Then silica was coated on the obtained nanoparticles and the whole composite was functionalized with chlorosulfonic acid in CH2Cl2. The obtained nanocomposite (Fe3O4@SiO2-SO3H) was characterized by FT-IR, VSM and XRD techniques and was used as an efficient catalyst in condensation reaction of indoles and aldehydes, and excellent yields of the desired products were obtained. The catalyst was recycled and used for successive runs with no considerable loss of activity. The indole products in their conjugated form were capable of selective sensing of CN- anion in solution.
Physical chemistry
Nasrin Sohrabi; Maryam Dookheh
Volume 3, Issue 3, pp. 180-282,Serial No. 8 , July 2015, , Pages 254-265
Abstract
In this study at first , an azo dye, 2,7- naphthalenediol, 2-[(4-Bromophenyl)azo (BPAND) as a ligand has been synthesized by addition of p-Bromoaniline to the modified montomorillonite K10 clay. This ligand was characterized using 1H-NMR, UV-Vis and IR spectroscopies. Subsequently, its interaction with ...
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In this study at first , an azo dye, 2,7- naphthalenediol, 2-[(4-Bromophenyl)azo (BPAND) as a ligand has been synthesized by addition of p-Bromoaniline to the modified montomorillonite K10 clay. This ligand was characterized using 1H-NMR, UV-Vis and IR spectroscopies. Subsequently, its interaction with calf thymus deoxyribonucleicacid ,ct-DNA was investigated in 5 mM phosphate buffer solution, pH=7 using UV-Vis absorption, thermal denaturation and viscosity measurement. From spectrophotometric titration experiments, the binding constant of BPAND with ct-DNA was found to be (2.89±0.2)×107 M-1 at 25°C. In order to determine changes in thermodynamic properties such as binding constant, Gibbs free energy, binding enthalpy and binding entropy, this experiment was done at various temperatures. The enthalpy and entropy changes were -2.852±0.634 kJ/mol and -814.065 ±2.52 J/mol.K, respectively.Thermal denaturation experiments show the increasing of melting temperature of ct-DNA (about 0.06°C less than 0.6) due to binding of BPAND ligand. From these results the mechanism and the stoichiometry of binding were determined. The results revealed that this interaction is exothermic (negative enthalpy change) along with negative entropy change. Therefore, the driving force in these interactions is enthalpy and the process is enthalpy-driven and suggest that the main driving force for the ct-DNA-BPAND complex formation is being Van der Waals or hydrogen binding.
Physical chemistry
Bahram Hosseini nia; Azam Anaraki Firooz; Masoumeh Ghalkhani; Javad Beheshtian
Volume 4, Issue 4, pp. 359-490, Serial No. 13 , October 2016, , Pages 483-492
Abstract
In this study, undoped ZnO and doped with Fe and Mn nanostructures were synthesized by hydrothermal method. The morphology of nanostructures was characterized by Scanning Electron Microscope. The electrochemical response of the carbon paste electrode modified with nanoparticles of ZnO and also ZnO doped ...
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In this study, undoped ZnO and doped with Fe and Mn nanostructures were synthesized by hydrothermal method. The morphology of nanostructures was characterized by Scanning Electron Microscope. The electrochemical response of the carbon paste electrode modified with nanoparticles of ZnO and also ZnO doped with Fe and Mn toward levodopa (L-Dopa) was studied. Studies of cyclic voltammetry using provided modified electrode showed electro catalytic properties for electro-oxidation of L-Dopa and a significant reduction in anodic over voltage compared to bare electrode was observed. Best response was obtained in terms of the current enhancement, overvoltage reduction, and reversibility improvement of the L-Dopa oxidation reaction under experimental conditions by modified electrode with zinc oxide nanoparticles doped with iron.
Physical chemistry
Hossein Ghanadzadeh; Ali Ghanadzadeh; Behnam Hosseini nia; Adel Eftekhari
Volume 5, Issue 1, pp. 1-120, Serial No. 14 , January 2017, , Pages 7-15
Abstract
Liquid-Liquid equilibrium data for the (water + Lactic acid + 2-ethy-1-hexanol) ternary system in T=298.2K and P=1atm were determined and tie- lines related to equilibrium data has been drawn in the phases diagram . The reliability of the experimental tie-line data for this system was as confirmed by ...
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Liquid-Liquid equilibrium data for the (water + Lactic acid + 2-ethy-1-hexanol) ternary system in T=298.2K and P=1atm were determined and tie- lines related to equilibrium data has been drawn in the phases diagram . The reliability of the experimental tie-line data for this system was as confirmed by using the Hand and Othmer –Tobias correlations. The tie-line data were correlated by means of the UNIQUAC equation for this ternary system , The average root mean square deviation between the observed and calculated mass fractions was 0.66%. A comparison of the extracting capabilities of this solvent by 1-octanol was made with respect to distribution coefficients and separation factors bases. The results show that extraction of lactic acid from aqueous solutions by 2-Ethyl-1-hexanol is possible and 2-Ethyl-1-hexanol is more appropriate than the other octanol isomer.
Nanochemistry
Jamal Afzali; Sedigheh Sadegh Hassani
Volume 3, Issue 3, pp. 180-282,Serial No. 8 , July 2015, , Pages 266-275
Abstract
Magnetic force microscope ( MFM ) is a powerful technique for mapping the magnetic force gradient above the sample surface. Herein, single-wall carbon nanotubes (SWCNT) were used to fabricate MFM probe by dielectrophoresis method which is a reproducible and cost-effective technique. The effect of induced ...
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Magnetic force microscope ( MFM ) is a powerful technique for mapping the magnetic force gradient above the sample surface. Herein, single-wall carbon nanotubes (SWCNT) were used to fabricate MFM probe by dielectrophoresis method which is a reproducible and cost-effective technique. The effect of induced voltage on the deposition manner of carbon nanotubes (CNT) on the atomic force microscope ( AFM ) tip was investigated . The optimum voltage and frequency of SWCNT solution are obtained as 13 volts and 2 MHz, respectively. After coating theas-prepared CNT tips with a layer of cobalt,it can be used to obtain high resolution MFM images.
Applied Chemistry
Soleyman Hosseinzadeh; Shahryar Pashaei; Nazanin Moludpoor
Volume 5, Issue 1, pp. 1-120, Serial No. 14 , January 2017, , Pages 16-27
Abstract
A series of polystyrene hybrid nanocomposites have been fabricated with varying amounts of TiO2 viz., 0, 0.5 and 1 % w/w along with 3% TS by in-situ polymerization method. The influence of surface modified TiO2 nanoparticles on the thermal properties of PS matrix was examined using thermogravimetry and ...
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A series of polystyrene hybrid nanocomposites have been fabricated with varying amounts of TiO2 viz., 0, 0.5 and 1 % w/w along with 3% TS by in-situ polymerization method. The influence of surface modified TiO2 nanoparticles on the thermal properties of PS matrix was examined using thermogravimetry and differential scanning calorimetry. Thermal characteristics of the polystyrene/TS/TiO2 hybrid nanocomposites were evaluated by using differential scanning calorimetric (DSC), thermal analysis (DTA), thermogravimetric analysis (TGA) and dynamic mechanical thermal analysis (DMA). By comparison with the values obtained for the hybrid mixed composites, the thermal properties of 1wt. % TiO2 along with 3wt.% TS are increased. On the other hand, PS/TS/TiO2 nanocomposites have higher glass transition temperature and better thermal and thermo oxidative stability than the bare PS. The morphological behaviors of the prepared polystyrene/TS/TiO2 were analyzed using SEM.
Organic chemistry
Abdoulhossien Massoudi; Azam Louie; Omid Louie
Volume 3, Issue 3, pp. 180-282,Serial No. 8 , July 2015, , Pages 276-282
Abstract
Poly methyl methacrylate (PMMA) is the most common material used in Prosthodontics. Several studies indicate a breakdown of the number of very high resin bases after 2 to 3 years to avoid breaking bass and several attempts have been made, such as altering the chemical structure of resin by adding causes ...
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Poly methyl methacrylate (PMMA) is the most common material used in Prosthodontics. Several studies indicate a breakdown of the number of very high resin bases after 2 to 3 years to avoid breaking bass and several attempts have been made, such as altering the chemical structure of resin by adding causes cross linking or copolymerization. The innovative method for improving the physical properties of the prosthesis and increase its strength, a copolymer of styrene - methyl methacrylate was proposed. Tensile strength increased with the increase of styrene with methyl methacrylate in an amount determined to be the most resistant. Polystyrene and poly methyl methacrylate and copolymers characterized by FTIR, CNMR and Tg and tensile strength were measured according to ISO1567 standard.
Physical chemistry
Mehdi Ghambarian; Zahra Azizi; Mohammad Ghashghaee
Volume 5, Issue 1, pp. 1-120, Serial No. 14 , January 2017, , Pages 28-34
Abstract
Density-functional-based and ab initio calculations were implemented at different computational levels to estimate the binding energy of Zn2+ ion adsorbed on the available sites of a silicate MEL-type adsorbent. B3LYP and MP2 were used in combination with the 6-31G*, 6-31+G*, LanL2DZ, 6-311+G*, and Def2-TZVP ...
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Density-functional-based and ab initio calculations were implemented at different computational levels to estimate the binding energy of Zn2+ ion adsorbed on the available sites of a silicate MEL-type adsorbent. B3LYP and MP2 were used in combination with the 6-31G*, 6-31+G*, LanL2DZ, 6-311+G*, and Def2-TZVP basis sets. The zinc cation was found to preferentially occupy the 6MR sites followed by the cage-like positions. Nevertheles, all of the available sites exhibited negative amounts for the Gibbs free energy and enthalpy of adsorption with the corresponding population-averaged values of –160.84 and –169.53 kcal/mol at the B3LYP/Def2-TZVP level. Overall, the B3LYP/LanL2DZ method illustrated the highest deviation from the others both in trends and absolute values of binding energy. While the absolute binding energy ranged from 131.23 to 230.79 kcal/mol over different sites, the population-averaged binding energies altered from 146.08 to 162.54 kcal/mol depending on the method employed.
Organic chemistry
Asadollah Farhadi; Mohammad Ali Takassi; Lila Hejazi
Volume 5, Issue 1, pp. 1-120, Serial No. 14 , January 2017, , Pages 35-41
Abstract
The chemistry of 2-oxo-1,2,3,4-tetrahydropyrimidines began to develop toward the end of 1893 year, when the first representatives of this class compounds were reported by P. Biginelli. Despite prior reports of several really effective catalytic and non-catalytic approaches towards Biginelli-type products, ...
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The chemistry of 2-oxo-1,2,3,4-tetrahydropyrimidines began to develop toward the end of 1893 year, when the first representatives of this class compounds were reported by P. Biginelli. Despite prior reports of several really effective catalytic and non-catalytic approaches towards Biginelli-type products, an overwhelming number of new catalysts for the Biginelli reaction have been recently published. Most of the catalysts are somewhat exotic, expensive, harmful and even ineffective in the absence of acidic additives. This work reports on the preparation of 2-oxo-1,2,3,4-tetrahydropyrimidines using the NaF as catalyst. One-pot condensation reactions were carried out for various aryl aldehydes, ethyl acetoacetate, acetyl acetone and urea under solvent-free conditions at 100 °C and afforded the target molecules in good to excellent yields. The advantages of this method are high yield of product, short reaction time, and separation of this catalyst is very comfortable. Furthermore, according to the experimental data, we have proposed the suitable mechanism.
Analytical chemistry
Banafsheh Norouzi
Volume 5, Issue 1, pp. 1-120, Serial No. 14 , January 2017, , Pages 42-51
Abstract
A sodium dodecyl sulfate modified carbon paste electrode (SDS/CPE) was developed in this work based on the surface modification method. The modified electrode was prepared by immersing SDS/CPE in a nickel nitrate solution. This electrode showed a strong accumulation ability toward nickel ions. Then modified ...
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A sodium dodecyl sulfate modified carbon paste electrode (SDS/CPE) was developed in this work based on the surface modification method. The modified electrode was prepared by immersing SDS/CPE in a nickel nitrate solution. This electrode showed a strong accumulation ability toward nickel ions. Then modified electrode was conditioned by potential recycling in a potential range of 0.2–0.8 V (vs. Ag/AgCl/KCl) by cyclic voltammetry in alkaline medium. The results showed that the Ni/SDS on the electrode behaves as an efficient catalyst for the electrooxidation of methanol in alkaline medium via Ni (III) species formed on the electrode. Moreover, the effects of various parameters such as SDS concentration, methanol concentration, NaOH concentration and nickel nitrate concentration on the electrooxidation of methanol have also been investigated.
Organic chemistry
Rahimeh Hajinasiri; Sanaz Baravardeh; Sobhan Rezayati
Volume 5, Issue 1, pp. 1-120, Serial No. 14 , January 2017, , Pages 52-57
Abstract
Derivatives of thiazolidinone ring systems are known to act as anti-HIV infections , analgesic, anti-bacterial, anti-convulsant, anti parasitic, potential anti-inflammatory and herbicidal agents. Due biological activities of thiazolidinones ring, several methods for their synthesis have been illustrated ...
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Derivatives of thiazolidinone ring systems are known to act as anti-HIV infections , analgesic, anti-bacterial, anti-convulsant, anti parasitic, potential anti-inflammatory and herbicidal agents. Due biological activities of thiazolidinones ring, several methods for their synthesis have been illustrated in literature. Imidazolidine-2-thiones were synthesized by the oxidative cyclization of 1-benzoyl-3-aryl-thioureas with bromine and enolizable carbonyl compounds in the presence of excess triethylamine . A suitable method for the synthesis of fused thiazoles were described from the reaction of aroylphenyl thioureas with π-acceptor quinones. An efficient and one-pot method for the synthesis alkyl 2-(1-alkyl-5-oxo-3-phenyl-2-thioxotetrahydro-4H-imidazol-4-yliden) acetate derivatives via simple reaction between isoquinoline, dialkyl acetylenedicarboxylate and benzyl phenylthiourea under solvent-free conditions without using any additional catalyst, is described. The mild reaction conditions and good yields and exhibit the synthetic advantage of this method. Also this method is environmentally friendly.
Organic chemistry
Bozorg Maddah
Volume 5, Issue 1, pp. 1-120, Serial No. 14 , January 2017, , Pages 58-66
Abstract
A mild and efficient one-pot three-component and environmentally benign approach for the synthesis of a wide range of hydantoin annulated derivatives has been described. A multi-component reaction between a carbonyl compounds (ketone or aldehyde), potassium cyanide and ammonium carbonate (as cyanating ...
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A mild and efficient one-pot three-component and environmentally benign approach for the synthesis of a wide range of hydantoin annulated derivatives has been described. A multi-component reaction between a carbonyl compounds (ketone or aldehyde), potassium cyanide and ammonium carbonate (as cyanating agent and amine source, respectively leads to the formation of hydantoins. The proposed optimized reaction conditions ,i.e. solvent-free conditions under ambient temperature in the presence of low amount of ZnOnano-catalyst, were very efficient resulting in the formation of the desired products with good to excellent yields. Furthermore, the presented methodology is in accord with green chemistry principles.Keywords: Bucherer-Bergs; hydantoin derivatives; multicomponent reactions (MCRs); green chemistry.
Inorganic chemistry
Reza Ghiasi; Amir Hossein Hakimiounb
Volume 5, Issue 1, pp. 1-120, Serial No. 14 , January 2017, , Pages 67-78
Abstract
Equilibrium geometry, electronic structures, and vibrational modes of CoB8- were investigated in the PBEPBE/6-311+G(d,p) level of theory. The nucleus independent chemical shift (NICS) analysis and magnetizability values were used for studying of aromaticity in CoB8-. The effects of different solvents ...
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Equilibrium geometry, electronic structures, and vibrational modes of CoB8- were investigated in the PBEPBE/6-311+G(d,p) level of theory. The nucleus independent chemical shift (NICS) analysis and magnetizability values were used for studying of aromaticity in CoB8-. The effects of different solvents on the structure and frontier orbital energies were calculated using the polarizable continuum model (PCM). Quantum theory of atoms in molecules (QTAIM) was used for analysis of Co-B and BB bonds.Geometry optimization was performed using Perdew, Burke and Ernzerhof exchange functional and the gradient-corrected correlation functional of Perdew, Burke and Ernzerhof (PBEPBE) , and frequency calculation is done to confirm the status of the potential energy minimum.
Organic chemistry
Ghobad Mansouri
Abstract
Two polypyridyl copper(II) complexes, [Cu(phen)(phen-dione)Cl]Cl (1) and [Cu(bpy) (phen-dione)Cl]Cl (2), (where Phen =1,10-phenanthroline, bpy =2,2'-bipyridine and Phen-dione = 1,10-phenanthroline-5,6-dione), were used as efficient catalysts for the oxidation of benzyl alcohol to benzaldehyde. The effects ...
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Two polypyridyl copper(II) complexes, [Cu(phen)(phen-dione)Cl]Cl (1) and [Cu(bpy) (phen-dione)Cl]Cl (2), (where Phen =1,10-phenanthroline, bpy =2,2'-bipyridine and Phen-dione = 1,10-phenanthroline-5,6-dione), were used as efficient catalysts for the oxidation of benzyl alcohol to benzaldehyde. The effects of various parameters such as reaction temperature, reaction time, etc. were studied. The catalysts were stable at the operation conditions and recyclable. The conversion percentage for complex 1 was higher than the complex 2.
Analytical chemistry
Mehdi Nekoei
Volume 5, Issue 1, pp. 1-120, Serial No. 14 , January 2017, , Pages 79-98
Abstract
In this paper, the quantitative structure activity-relationship (QSAR) of the CCR2b receptor inhibitors was scrutinized. Firstly, the molecular descriptors were calculated using the Dragon package. Then, the stepwise multiple linear regressions (SW-MLR) and the genetic algorithm multiple linear regressions ...
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In this paper, the quantitative structure activity-relationship (QSAR) of the CCR2b receptor inhibitors was scrutinized. Firstly, the molecular descriptors were calculated using the Dragon package. Then, the stepwise multiple linear regressions (SW-MLR) and the genetic algorithm multiple linear regressions (GA-MLR) variable selection methods were subsequently employed to select and implement the prominent descriptors having the most significant contributions to the activities of the molecules. A combined data set including numerical values of inhibition activity data (IC50) of 103 CCR2b receptor derivatives was adopted for our simulations. This study revealed that both SW-MLR and GA-MLR methods consisted of six molecular descriptors. The adopted descriptors belong to topological, charge, RDF and atom-centered fragments classes. A comparison of results by the two methodologies indicated the superiority of GA-MLR over the SW-MLR method. The authenticity of the proposed model (GA-MLR) was further confirmed using the cross-validation, validation through an external test set and Y-randomization.
Organic chemistry
Abbas Mirzaie; Ahmad Afzalinia; Tahereh Musabeygi
Volume 5, Issue 1, pp. 1-120, Serial No. 14 , January 2017, , Pages 99-104
Abstract
Heteropoly acid promoted nanoparticle of nickel oxide samples were prepared by sol-gel method using heteropoly acids. Prepared composite was characterized by XRD, FT-IR and ICP technique. In this work, we have reported bromination of phenol, its derivatives and some aromatic compounds. The liquid phase ...
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Heteropoly acid promoted nanoparticle of nickel oxide samples were prepared by sol-gel method using heteropoly acids. Prepared composite was characterized by XRD, FT-IR and ICP technique. In this work, we have reported bromination of phenol, its derivatives and some aromatic compounds. The liquid phase bromination of phenol was Performed using heteropoly acids immobilized nanoparticle of nickel oxide as catalyst, KBr as brominating agent and hydrogen peroxide as an oxidant in acetonitrile at room temperature. The reaction proceeds through the formation of Br+ (bromonium ion), which attacks the phenol ring forming different brominated products. Prepared catalyst can be used several times without a significant decline in catalytic activity.
Organic chemistry
Hemant Chavan; Datta Survase; Sakharam Dongare; Vasant Helavi; Shreeram Ganapure
Volume 5, Issue 1, pp. 1-120, Serial No. 14 , January 2017, , Pages 105-114
Abstract
Regioselective synthesis of highly functionalized pyranopyrazoles was achieved in excellent yield from phenyl pyrazolone, substituted aromatic aldehyde with nitroketene-N,S-acetal in the presence of indium trichloride as a versatile catalyst under reflux condition in ethanol-water mixture. All reactions ...
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Regioselective synthesis of highly functionalized pyranopyrazoles was achieved in excellent yield from phenyl pyrazolone, substituted aromatic aldehyde with nitroketene-N,S-acetal in the presence of indium trichloride as a versatile catalyst under reflux condition in ethanol-water mixture. All reactions preceeded within a short period of time with excellent purity. All of the synthesized compounds were identified by IR, 1H NMR, 13C NMR and mass spectroscopy. Quantitative yields, inexpensive and environmentally friendly solvent system and simple work-up procedure are the attractive features of the present method. It is thus enviro-economic method without producing hazardous wastes. The formed pyranopyrazoles might find to possess important biological and pharmaceutical applications.
Sabah Shiri; Kamal Alizadeh; Naser Abbasi
Abstract
In the present research, salting out and vortex assisted dispersive liquid–liquid microextraction based on solidification of floating organic drop microextraction (SO-VADLLME-SFODME) for the extraction and determination of phenol and chlorophenols in water samples followed by HPLC have been ...
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In the present research, salting out and vortex assisted dispersive liquid–liquid microextraction based on solidification of floating organic drop microextraction (SO-VADLLME-SFODME) for the extraction and determination of phenol and chlorophenols in water samples followed by HPLC have been studied through a novel, simple, low-cost, selectable and environment friendly (so called green) method. Three approaches have been combined in a way that their advantages have been used while reducing their deficiencies. The effects of various empirical parameters such as pH, type and volume of dispersive solvent, the volume of extracted organic solvent, salt concentration, the condition of centrifuge, and mixing time were studied and optimal conditions were achieved by using Mini-Tab software and Respond Surface Methodology (RSM) based upon Box-Behnken Design (BBD) and Desirability Function (DF). Under the optimum conditions, calibration curves were linear in the range of 0.1 to 1000 μgL-1, limit of detections (LODs) were in the range of 0.06 to 0.34μgL-1 and r2>0.9916, respectively. The method was also utilized to measure phenol and chlorophenols in various water samples successfully resulted in extraction recoveries ranged from 92.8 to 103.9%.
Analytical chemistry
Ghobad Mansouri; Mohammd Bagher Gholivand; Zarrin Eshaghi
Abstract
A single-use electrochemical sensor using ionic liquid mediated hollow fiber-graphite working electrode was fabricated for the first time. The screening tool was developed by coupling this electrode with differential pulse voltammetry (DPV) for in-situ pre-concentration and determination of Zn(II) and ...
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A single-use electrochemical sensor using ionic liquid mediated hollow fiber-graphite working electrode was fabricated for the first time. The screening tool was developed by coupling this electrode with differential pulse voltammetry (DPV) for in-situ pre-concentration and determination of Zn(II) and Cu(II). In our plot, porous polypropylene hollow fiber membrane was divided into pieces of 2 cm, then fiber's lumen and pores were satiated with homogeneous mixture of reduced graphene oxide (rGO) and three types used ionic liquids:(1-ethyl-3-methylimidazolium tetrafuoroborate), (1-butyl-3-methylimidazoliumhexafluorophosphate) and (1-butyl-2,3-dimethylimidazolium hexafluorophosphate) individually. Thereafter, a pencil graphite rod was placed inside the fiber. Fabricated sensors were used for single-step simultaneous purification and determination of Zn(II) and Cu(II) ions from water samples. The response surface method (RSM) was used as the basis of the design and analysis of the experiments. Parameters that were mostly important in the separation part of the study, such as: molar mass of ionic liquids, amount of nanoparticle and sonication time have been investigated. Analysis of variance (ANOVA) and RSM contour plots were presented for effect of all factors (input parameters) on the maximum current of differential pulse voltammetry (DPV) peaks (output responses). The results disclosed that the metal removal was impressed by the molar mass of ionic liquids, amount of nanoparticle and sonication time respectively. The efficiency specifications of this procedure were evaluated by calculating precision and response linearity. Under the optimal experimental conditions linear concentration ranges of 0.9–550µgL-1 and 0.7–500 µgL-1 were obtained for Zn(II) and Cu(II) ions respectively. The reported limit of detection for Zn(II) and Cu(II) were 0.27 and 0.21µgL-1 with relative standard deviations (RSD) 3.2%, and 4.4%, respectively. In addition, this sensor was successfully applied to real water samples.
Organic chemistry
Mohammad Alikarami; Ahmad Nikseresht; Tayebeh Amoozadeh
Abstract
Benzimidazoles are among the most important nitrogen-containing heterocyclic compounds that have many pharmaceutical applications; including, antitumor, anticancer, anticorrosive, antibacterial, irritant and enzymatic interceptors. In this research, the synthesis of benzimidazoles using o-phenylenediamine ...
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Benzimidazoles are among the most important nitrogen-containing heterocyclic compounds that have many pharmaceutical applications; including, antitumor, anticancer, anticorrosive, antibacterial, irritant and enzymatic interceptors. In this research, the synthesis of benzimidazoles using o-phenylenediamine and aldehyde derivatives in the presence of the nano montemurillonite in solvent-free and room temperature conditions has been investigated. All products with relatively good yields were identified by spectral and physical methods.
Organic chemistry
Abdolkarim Zare; Manije Dianat; Nahid Varavi; Mina Aali-Hosaini; Hanafieh Deisi
Abstract
Nano-silica-bonded 3-n-propyl-1-sulfonic acid imidazolium chloride (nano-SB-[PSIM]Cl) was applied as a highly efficient, general and heterogeneous catalyst for one pot multi-component reaction of 2-naphthol, arylaldehydes, and thioacetamide leading to 1-thioamidolakyl-2-naphthols. All reactions proceeded ...
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Nano-silica-bonded 3-n-propyl-1-sulfonic acid imidazolium chloride (nano-SB-[PSIM]Cl) was applied as a highly efficient, general and heterogeneous catalyst for one pot multi-component reaction of 2-naphthol, arylaldehydes, and thioacetamide leading to 1-thioamidolakyl-2-naphthols. All reactions proceeded with excellent yields in short times under solvent-free conditions. Our protocol was superior than most of the reported methods for the preparation of 1-thioamidolakyl-2-naphthols in terms of some factors included relatively short reaction times, moderate to high yields, and absence of organic solvents.