Original Research Article
Organic chemistry
Mohammad Reza Poor Heravi; Hassan Karami; Bagher Mohammadi; Vahid Azizkhani
Abstract
An efficient and convenient synthesis of novel tetrahydrobenzo[c]acridin-8(7H)-one derivatives is described using the electrogenerated anion of acetonitriles as the base in the presence of tetrabutylammonium fluoride as an effective supporting electrolyte in a one-pot, three-component condensation of ...
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An efficient and convenient synthesis of novel tetrahydrobenzo[c]acridin-8(7H)-one derivatives is described using the electrogenerated anion of acetonitriles as the base in the presence of tetrabutylammonium fluoride as an effective supporting electrolyte in a one-pot, three-component condensation of aromatic aldehyde, dimedone and 1-naphthyl amine. The reaction is carried out in an undivided cell containing an iron cathode and a graphite anode under a constant current density of 5 mA/cm2 (I=20 mA, electrode surface=5 cm2) in CH3CN at room temperature was found to be optimum for the electrochemically induced chain process and resulted in the highest yield. An efficient and convenient synthesis of novel tetrahydrobenzo[c]acridin-8(7H)-one derivatives is described using the electrogenerated anion of acetonitriles as the base in the presence of tetrabutylammonium fluoride as an effective supporting electrolyte in a one-pot, three-component condensation of aromatic aldehyde, dimedone and 1-naphthyl amine. The reaction is carried out in an undivided cell containing an iron cathode and a graphite anode under a constant current density of 5 mA/cm2 (I=20 mA, electrode surface=5 cm2) in CH3CN at room temperature was found to be optimum for the electrochemically induced chain process and resulted in the highest yield.
![Electrocatalytic multicomponent assembling of aldehydes, dimedone and 1-naphthylamine for synthesis of novel tetrahydrobenzo[c]acridin-8(7H)-one derivatives](data/icc/coversheet/781508583888.jpg)
Original Research Article
Organic chemistry
Sayed Hossein Banitaba
Abstract
An improved rapid one-pot and green synthesis of substituted pyranopyranes by condensing Kojic acid, malononitrile, and different aldehydes and using a catalytic amount of cobalt nanoparticles as green and reusable catalyst is reported for the first time. The reaction proceeds in aqueous media at ambient ...
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An improved rapid one-pot and green synthesis of substituted pyranopyranes by condensing Kojic acid, malononitrile, and different aldehydes and using a catalytic amount of cobalt nanoparticles as green and reusable catalyst is reported for the first time. The reaction proceeds in aqueous media at ambient temperature. Furthermore, the structural and morphological study of the cobalt nanoparticles was carried out using scanning electron microscopy (SEM), energy dispersive X-ray spectrum (EDS), and Dynamic light scattering (DLS) techniques. Utilization of simple procedure, high yields and the ease of separation of pure product, ease of catalyst separation by an external magnet and convenient manipulation, that makes this methodology as an interesting option for green synthesis of 2-amino-dihydropyranopyran-3-carbonitriles.
![A mild protocol for the preparation of 2-amino-dihydropyrano[3,2-b] pyran-3-carbonitriles via cobalt nanoparticles-catalyzed multi-component reaction in water](data/icc/coversheet/271508660737.jpg)
Original Research Article
Organic chemistry
Masoud Mohammadi Zeydi; Mahdi Fouladi; Mahnaz Shamsi-Sani; Nosrat Ollah Mahmoodi
Abstract
In this work, Nano TiO2@KSF used as an efficient, homogeneous and reusable catalyst for the synthesis of pyrano[2,3-d]-pyrimidinone derivatives via three-component reactions between malononitrile, barbituric acid and various aldehydes in water. The products were formed in high yields within short reaction ...
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In this work, Nano TiO2@KSF used as an efficient, homogeneous and reusable catalyst for the synthesis of pyrano[2,3-d]-pyrimidinone derivatives via three-component reactions between malononitrile, barbituric acid and various aldehydes in water. The products were formed in high yields within short reaction times. Also, this catalyst can be reused several times without loss of its catalytic activity. All the products were characterized using melting point and a variety of techniques, including infrared spectra (FT-IR) and were compared with trusty references. This method a simple, efficient and green for the preparation of pyrano[2,3-d]pyrimidinone (4a-4l) derivatives using TiO2@KSF under mild conditions. The promising reasons for the presented method is efficiency, generality reaction profile, mild and green reaction conditions, easy work-up procedure, short reaction times and high yields of the products, ease of preparation.
Original Research Article
Organic chemistry
Hamid Saeidian; Masomeh Faghfori; Morteza Abdoli
Abstract
A one pot green three‐component coupling reaction of aldehyde, phenylacetylene, and amine derivatives in the presence of copper (II)–thioamide combination as a novel and efficient heterogeneous catalyst under solvent–free conditions is reported. The catalyst displayed high activity and ...
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A one pot green three‐component coupling reaction of aldehyde, phenylacetylene, and amine derivatives in the presence of copper (II)–thioamide combination as a novel and efficient heterogeneous catalyst under solvent–free conditions is reported. The catalyst displayed high activity and afforded the corresponding propargylamines in good to high yields. The key to this procedure was the generation of Cu (I) required for the A3 coupling reaction, which was achieved by in situ reduction of Cu (II) using thiobenzanilide as reduction agent and ligand. The structure of the products was confirmed by 1H NMR, 13C NMR and EI-MS and comparison with authentic samples prepared by reported methods
Original Research Article
Analytical chemistry
Fatemeh Moeinpour; Zarrin Eshaghi
Volume 7, Issue 2, pp. 90-159, Serial No. 23 , April 2019, Pages 126-138
Abstract
The objective of this study is to design a simple, fast, sensitive and single-use electrode with the simultaneous capability of preconcentration and measuring, for application in a three-electrode voltammetry system to identify and measure the heavy metal cadmium. The design process of this sensor consists ...
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The objective of this study is to design a simple, fast, sensitive and single-use electrode with the simultaneous capability of preconcentration and measuring, for application in a three-electrode voltammetry system to identify and measure the heavy metal cadmium. The design process of this sensor consists of several stages. The polyurethane foam and multi walled carbon nanotubes nanoparticles were functionalized and the new nanocomposite was synthesized that with the help of an organic solvent, established on the pencil graphite electrode that was covered with hollow fiber. In this work, for the first time, the organic solvent was employed instead of ionic liquid. The designed sensor was used to detect and measure heavy metal cadmium through differential pulse voltammetry technique, which appearance of a sharp peak at -0.82 V indicates the presence of cadmium. It was found that the presence of air molecules as the analyte carrier (between hollow fiber cavities and in fixed nanocomposite on the graphite) instead of organic solvents or ionic liquids was desirable. All the synthesis stages of nanocomposite were analyzed by infrared spectroscopy. Finally, the nanocomposite morphology was obtained with a Scanning Electron Microscope. A calibration curve was drawn and linear response with a range of 2.39 to 47.6 µM was plotted. The LOD of the designed sensor was 0.399 µM for cadmium. The mentioned sensor was used to recognize and analyte measurement in real biological samples of urine, nail, and wastewater of the laboratory.
Original Research Article
Organic chemistry
Abdolkarim Zare; Jalal Sanjideh
Abstract
Two highly efficient protocols for the production of bis-coumarins under solvent-free conditions have been introduced. The reaction of 4-hydroxycoumarin (2 eq.) with arylaldehydes (1 eq.) using phthalimide-N-sulfonic acid (PhtSA) or isatin-N-sulfonic acid (IsSA), as solid-acid catalysts, afforded the ...
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Two highly efficient protocols for the production of bis-coumarins under solvent-free conditions have been introduced. The reaction of 4-hydroxycoumarin (2 eq.) with arylaldehydes (1 eq.) using phthalimide-N-sulfonic acid (PhtSA) or isatin-N-sulfonic acid (IsSA), as solid-acid catalysts, afforded the mentioned compounds with good to excellent yields in short times.Briefly, we have introduced two new SO3H-bearing solid-acid catalysts, entitled phthalimide-N-sulfonic acid and isatin-N-sulfonic acid, for the preparation of bis-coumarins. The advantages of the presented protocols include: high effectuality and generality of the catalysts, high to excellent yields, short reaction times, simple synthesis of the catalysts from available and inexpensive starting materials, easy work-up and purification of the products, relatively mild conditions, application of solvent-free technique, and good compliance with the green chemistry protocols.
Original Research Article
Organic chemistry
Milad Edraki; Issa Mousazadeh Moghadam; Mohammad Banimahd Keivani; Mohammad Hossein Fekri
Abstract
Corrosion inhibitory impacts of turmeric with concentrations of 200-800 ppm on the electrochemical behavior of mild steel were studied in the medium of NaCl 3.5% using several techniques such as electrochemical impedance spectroscopy (EIS) and polarization. Scanning electron microscopy (SEM) was used ...
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Corrosion inhibitory impacts of turmeric with concentrations of 200-800 ppm on the electrochemical behavior of mild steel were studied in the medium of NaCl 3.5% using several techniques such as electrochemical impedance spectroscopy (EIS) and polarization. Scanning electron microscopy (SEM) was used for analyzing the surface of mild steel after 24 hours of immersion in the electrolyte solution, with and without turmeric. The results of polarization and EIS demonstrated that for the steel sample immersed in a salt solution containing 800 ppm of turmeric extract, the corrosion current density was decreased and the corrosion potential was shifted to positive values. On the other hand, the electric capacitance of the double-layer was decreased and the charge transfer resistance and inhibition efficiency were increased, confirming an improved corrosion resistance compared to the other sample concentrations. SEM results for the mentioned inhibitor with 800 ppm concentration showed a more even and continuous film formed on the surface of mild steel and no corrosion products was observed.
![Electrocatalytic multicomponent assembling of aldehydes, dimedone and 1-naphthylamine for synthesis of novel tetrahydrobenzo[c]acridin-8(7H)-one derivatives](javascript:loadModal('Electrocatalytic multicomponent assembling of alde ... ', 'data/icc/coversheet/781508583888.jpg'))
![A mild protocol for the preparation of 2-amino-dihydropyrano[3,2-b] pyran-3-carbonitriles via cobalt nanoparticles-catalyzed multi-component reaction in water](javascript:loadModal('A mild protocol for the preparation of 2-amino-dih ... ', 'data/icc/coversheet/271508660737.jpg'))
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