reusable catalyst

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1 - Brønsted Acidic Ionic Liquid: An Efficient and Reusable Catalyst for the Multi-Component Synthesis of Dihydropyrimidinones under Solvent-Free Conditions
Heshmatollah Alinezhad Neda Ghobadi

An efficient and convenient procedure for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones and thiones by condensation of 1,3-dicarbonyl compounds, Aromatic and aliphatic aldehydes, and urea or thiourea in the presence of catalytic amount of Brønsted acidic ionic أکثر

An efficient and convenient procedure for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones and thiones by condensation of 1,3-dicarbonyl compounds, Aromatic and aliphatic aldehydes, and urea or thiourea in the presence of catalytic amount of Brønsted acidic ionic liquid 3-methyl-1-sulfonic acid imidazolium chloride {[Msim]Cl} under thermal solvent-free conditions reacted easily to afford the corresponding 3,4-dihydropyrimidin-2(1H)-ones and thiones. Straightforward and clean workup, short reaction time, good to excellent yields and reusability of the catalyst are the advantages of this method. تفاصيل المقالة

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2 - Bronsted Acidic Ionic Liquid: An Efficient and Reusable Catalyst for the Multi-Component Solvent-Free Synthesis of Dihydropyrimidinones
Heshmatollah Alinezhad Neda Ghobadi

An efficient and convenient procedure for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones and thiones by condensation of 1,3-dicarbonyl compounds, Aromatic and aliphatic aldehydes, and urea or thiourea in the presence of catalytic amount of Brønsted acidic ionic أکثر

An efficient and convenient procedure for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones and thiones by condensation of 1,3-dicarbonyl compounds, Aromatic and aliphatic aldehydes, and urea or thiourea in the presence of catalytic amount of Brønsted acidic ionic liquid 3-methyl-1-sulfonic acid imidazolium chloride {[Msim]Cl} under thermal solvent-free conditions reacted easily to afford the corresponding 3,4-dihydropyrimidin-2(1H)-ones and thiones. Straightforward and clean workup, short reaction time, good to excellent yields and reusability of the catalyst are the advantages of this method تفاصيل المقالة

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3 - 1-(1-Propylsulfonic)-3-methylimidazolium chloride Brønsted acidic ionic liquid catalyzed one-pot synthesis of 14-aryl-14H-dibenzo[a,j]xanthene derivatives under solvent-free conditions
Sima Abbaspour Mogharab Torabi Jafroudi Shima Haghi Sohan Rezayati

A rapid, green and efficient method for the synthesis of 14-aryl-14H-dibenzo[a,j]xanthene derivatives through a one-pot condensation of 2-naphthol with various aromatic aldehydes in the presences of several acidic ionic liquids including [PSMIM]Cl, [BMIM]HSO4, [BMIM]Cl, أکثر

A rapid, green and efficient method for the synthesis of 14-aryl-14H-dibenzo[a,j]xanthene derivatives through a one-pot condensation of 2-naphthol with various aromatic aldehydes in the presences of several acidic ionic liquids including [PSMIM]Cl, [BMIM]HSO4, [BMIM]Cl, [BMIM]Br, and [BMIM]BF4 as organocatalysts and task-specific acidic ionic liquids (AILs) under solvent-free conditions is described. Compared with other synthetic methods, this new method has the advantages such as milder reaction conditions, good to excellent yields, short reaction times, and environmentally benign procedure. Also, 1-(1-Propylsulfonic)-3-methylimidazolium chloride [PSMIM]Cl acts as a catalyst under solvent-free conditions and can be recovered and reused six times without apparent loss of its catalytic activity. تفاصيل المقالة

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4 - Synthesis of pyrazolopyranopyrimidines catalyzed by caffeine supported on boehmite nanoparticles and their evaluation for anti-bacterial activities
Mohammad Bakherad Rahele Doosti Mahdi Mirzaee Khosrow Jadidi

The reaction of 3-chloropropyl boehmite nanoparticles with caffeine and sulfuric acid afforded BNPs-3-propyl-imidazolopyridinium hydrogen sulfate [BNPs-Caff]HSO4 as a new BNPs-supported ionic liquid (IL) catalyst. [BNPs-Caff]HSO4 proved to be an efficient heterogeneous أکثر

The reaction of 3-chloropropyl boehmite nanoparticles with caffeine and sulfuric acid afforded BNPs-3-propyl-imidazolopyridinium hydrogen sulfate [BNPs-Caff]HSO4 as a new BNPs-supported ionic liquid (IL) catalyst. [BNPs-Caff]HSO4 proved to be an efficient heterogeneous catalyst for the synthesis of pyrazolopyranopyrimidines via a one-pot four-component reaction of hydrazine hydrate, ethyl acetoacetate, barbituric acid, and an aldehyde. The attractive features of this method are simple procedure, clean reaction, use of a reusable catalyst, easy workup, and performing a multi-component reaction (MCR) in water. A number of synthesized compounds were screened for their in vitro anti-bacterial activities against the Gram-positive and Gram-negative bacteria using a well-diffusion method. تفاصيل المقالة

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5 - Synthesis of dihydrofurans using biosynthesized CuO nanoparticles
Javad Safaei-Ghomi Hossein Shahbazi-Alavi

The preparation of trans-dihydrofurans has been achieved by a one-pot condensation reaction of 4-bromophenacyl bromide, aromatic aldehydes and 5,5-dimethyl-1,3-cyclohexanedione using biosynthesized CuO nanoparticles under reflux conditions in ethanol. CuO nanoparticles أکثر

The preparation of trans-dihydrofurans has been achieved by a one-pot condensation reaction of 4-bromophenacyl bromide, aromatic aldehydes and 5,5-dimethyl-1,3-cyclohexanedione using biosynthesized CuO nanoparticles under reflux conditions in ethanol. CuO nanoparticles (CuO NPs) were prepared using extractof leaves of Ajuga chamaecistus Subsp. Scoparia. The key advantages of this process are the diastereoselective synthesis, reusability of the catalyst, low catalyst loading, excellent yields, short reaction times, simple workup and environmentally benign. Fully optimized structures of trans and cis dihydrofurans were obtained by B3LYP/6-31G(d,p) method. The structures of the prepared trans-2,3-dihydrofurans were fully characterized by 1H and 13C NMR spectra, IR spectra, and elemental analysis. تفاصيل المقالة

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6 - ZrP2O7 nanoparticles as a robust and efficient catalyst for the synthesis of 2-aryl-5-methyl-2,3-dihydro-1H-3-pyrazolones under microwave irradiation
Javad Safaei-Ghomi Esmaeil Afkhami Hossein Shahbazi-Alavi Abolfazl Ziarati

ZrP2O7 nanoparticles have been used as an efficient catalyst for the preparation of 2-aryl-5-methyl-2,3-dihydro-1H-3-pyrazolones by a simple one-pot four-component reaction of phenyl hydrazines, ethyl acetoacetate ,β-naphthol and benzaldehydes under microwave irrad أکثر

ZrP2O7 nanoparticles have been used as an efficient catalyst for the preparation of 2-aryl-5-methyl-2,3-dihydro-1H-3-pyrazolones by a simple one-pot four-component reaction of phenyl hydrazines, ethyl acetoacetate ,β-naphthol and benzaldehydes under microwave irradiation in good to excellent yields. When the reaction was carried out using ZrOCl2.8H2O, ZrO2 and ZrP2O7 NPs as the catalyst, the product were obtained in moderate to good yield. The highest yield 92% was reached when the reaction was performed with 0.6 mol% of catalyst loading. Atom economy, green reaction, short reaction times, easy isolation of the targeted molecules, recovery and reusability of the catalyst are some of the important features of this protocol. تفاصيل المقالة

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7 - Li(OHCH2CH2NH2)(CF3OAC): A novel and homogeneous acidic ionic liquid catalyst for efficient synthesis of 2-amino-4H-chromene derivatives
Esmayeel Abbaspour-Gilandeh Seyyedeh Cobra Azimi

The ionic liquid Li(OHCH2CH2NH2)(CF3OAC) was found to efficiently catalyze the three-component reaction between different enols, aldehydes, and malononitrile , leading to rapid synthesis of 2-amino-4H-chromene derivatives in fairly high yields. The catalyst is easily pr أکثر

The ionic liquid Li(OHCH2CH2NH2)(CF3OAC) was found to efficiently catalyze the three-component reaction between different enols, aldehydes, and malononitrile , leading to rapid synthesis of 2-amino-4H-chromene derivatives in fairly high yields. The catalyst is easily prepared, highly stable, simple to handle and recycled for several times without significant loss of activity. The method is simple, starts from readily accessible commercial starting materials, and provides biologically interesting products in good yields and short reaction times. The desired ionic liquids, for aromatic aldehyde leads to get the products. Heating was very effective in increasing the efficiency of the product and in the presence of heat, the desired products were created in a shorter time. تفاصيل المقالة

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8 - Nano-SiO2/hexamethylenetetramine promoted synthesis of pyrano[2,3-c] pyrazoles under solvent-free conditions
Bi Bi Fatemeh Mirjalili Mina Keihanfar

In this study, the nano-SiO2/hexamethylenetetramine as a new basic heterogeneous nanocatalyst was prepared and used for the synthesis of pyranopyrazole via the four-component reaction. Various aldehydes, hydrazine hydrate, ethyl acetoacetate and malononitrile were react أکثر

In this study, the nano-SiO2/hexamethylenetetramine as a new basic heterogeneous nanocatalyst was prepared and used for the synthesis of pyranopyrazole via the four-component reaction. Various aldehydes, hydrazine hydrate, ethyl acetoacetate and malononitrile were reacted at room temperature under solvent-free and grinding conditions. The morphology and structure of nano-catalyst were investigated by techniques such as FT-IR spectroscopy, FESEM, TEM, XRD, CHNS elemental analyzer and TGA. The structure of pyranopyrazoles was determined by spectroscopic data of FTIR and NMR. The principal affairs of this procedure are easy work-up, high yields, mild conditions and short reaction times. تفاصيل المقالة

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9 - Fe3O4@SiO2@IL‐PVP magnetic nanoparticles: Effective synthesis of spirooxindoles
Shahla Veysipour Masoud Nasr-Esfahani Zahra Rafiee Behrouz Eftekhari far

Various magnetite heterogeneous catalysts for the organic reaction are increasingly recognized while their stability still is a critical challenge. In this regard, SiO2, ionic liquid (IL), and polyvinyl pyrrolidone (PVP) were applied as a three-layer stabilization syste أکثر

Various magnetite heterogeneous catalysts for the organic reaction are increasingly recognized while their stability still is a critical challenge. In this regard, SiO2, ionic liquid (IL), and polyvinyl pyrrolidone (PVP) were applied as a three-layer stabilization system for modifying magnetic Fe3O4 to produce Fe3O4@SiO2@IL‐PVP as a novel nanocatalyst. The Fe3O4@SiO2@IL‐PVP as stabilized heterogeneous catalysts were utilized in a robust, and environmentally friendly strategy for the preparation of the spirooxindole derivatives by the one-pot condensation of isatin, malononitrile, and 1,3-dicarbonyl in a water solvent. The proposed method revealed a high yield spirooxindole derivatives preparation (99%) at short reaction times (1.0 min), low catalyst mass (0.002 g), and satisfactory temperature (30 °C) which confirm the lack of any tedious challenge and promising applicability and reusability. This work introduces a rational core-shell nanosystem design with a facile and novel construction strategy to arrive at nonexquisite metal-based composite catalysts with superior catalytic proficiency and prominent long-term stability. تفاصيل المقالة

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10 - Brønsted acidic ionic liquid ([BMIm]HSO4) as an efficient catalysts for the one-pot synthesis of 2H-indazolo[2,1-b]phthalazine-trione derivatives
Esmayeel Abbaspour-Gilandeh Seyyedeh Cobra Azimi

The Brønsted acidic ionic liquid ([BMIm]HSO4) catalyzed three-component synthesis of 2H-indazolo[2,1-b]phthalazine-trione derivatives at room temperature. The integrity of the ionic liquid remains reasonably unchanged when it is separated from the reaction mixtur أکثر

The Brønsted acidic ionic liquid ([BMIm]HSO4) catalyzed three-component synthesis of 2H-indazolo[2,1-b]phthalazine-trione derivatives at room temperature. The integrity of the ionic liquid remains reasonably unchanged when it is separated from the reaction mixture by water extraction, as it can be recycled several times without any loss of activity in each of the title syntheses. The products and ionic liquid could be conveniently separated from the reaction mixture, indicating that the whole process was performed as a green chemical transformation. The salient features of this one pot protocol are short reaction times, cleaner reaction profiles and simple workup. تفاصيل المقالة

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11 - Synthesis of tri and four substituted imidazoles derivatives using zinc oxid nanotubes modified by SiO2 as a powerful and reusable catalyst
Bijan Mombeni Godajdar Ebrahim Niknam

In recent years, zinc oxid nanotubes have attracted much attention. The direct use of , zinc oxidnanotubes modified by SiO2 as recoverable catalysts for organic reactions is very rare. The catalystswere characterized by XRD. The average particle size of ZnO catalysts is أکثر

In recent years, zinc oxid nanotubes have attracted much attention. The direct use of , zinc oxidnanotubes modified by SiO2 as recoverable catalysts for organic reactions is very rare. The catalystswere characterized by XRD. The average particle size of ZnO catalysts is 57 nm and there are highdensitydefects on nanotubes surfaces . A simple and efficient method for the imidazol derivativessynthesis from the condensation benzil and ammonium acetate with substituted aromatic aldehydesin the presence of a catalytic amount zinc oxid nanotubes modified by SiO2 is described. The reasonproposed for higher catalytic activity of zinc oxid nanotubes modified by SiO2 is a combinationeffect of the small particle size and high-density surface defects. The practical and simple methodled to excellent yields of the tri and four substituted imidazoles derivatives under mild conditionsand within short times. تفاصيل المقالة

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