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Carbon-Based Solid Acid as An Efficient and Reusable Catalyst for One-Pot Synthesis of Tetrasubstituted Imidazoles under Solvent-Free Conditions

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Chinese Journal of Chemistry 2011年第1期29卷 203-206页

作者： Tavakoli-Hoseini, Niloofar davoodnia, abolghasem Department of Chemistry Faculty of Sciences Islamic Azad University Mashhad Branch Mashhad lran

Carbon-based solid acid catalyst was found to be highly efficient, eco-friendly and recyclable heterogeneous catalyst for the multicomponent reaction of benzil, aromatic aldehyde, primary amine and ammonium acetate, giving rise to 1,2,4,5-tetrasubstituted imidazoles in good to excellent yields. The present methodology offers several advantages, such as high yields, short reaction time, mild reaction condition and a recyclable catalyst with a very easy work up.

关键词： carbon-based solid acid heterogeneous catalysis multicomponent reaction tetrasubstituted imidazole,solvent-free condition

PPA-SiO_2 catalyzed efficient synthesis of polyhydroquinoline derivatives through Hantzsch multicomponent condensation under solvent-free conditions

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Chinese Chemical Letters 2011年第7期22卷 807-810页

作者： Amir Khojastehnezhad Farid Moeinpour abolghasem davoodnia Department of Chemistry Faculty of SciencesIslamic Azad UniversityMashhad BranchMashhad 91735-413Iran Department of Chemistry Faculty of SciencesIslamic Azad UniversityBandar Abbas BranchIran

Silica gel-supported polyphosphoric acid （PPA-SiO2） was found to be an efficient catalyst for the one-pot four-component Hantzsch condensation reaction of aryl aldehydes, dimedone, ethyl acetoacetate and ammonium acetate to afford the corresponding polyhydroquinoline derivatives in high yields. The main advantages of the present approach are short reaction times, clean reaction profiles, simple experimental and workup procedures.

关键词： Multicomponent reaction One-pot synthesis Solvent-free Polyhydroquinoline derivatives Silica-supported polyphosphoric acid (PPA-SiO2)

Investigation into the Regiochemistry of Some Pyrazoles Derived from 1,3-Dipolar Cycloaddition of Methyl Meth- acrylate with Some Nitrilimines： A Combined Theoretical and Experimental Study

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Chinese Journal of Chemistry 2011年第6期29卷 1167-1172页

作者： Bakavoli, Mehdi Moeinpour, Farid davoodnia, abolghasem Morsali, Ali Department of Chemistry Islamic Azad University-Mashhad Branch Mashhad lran

1,3-Dipolar cycloaddition between methyl methacrylate as dipolarophile and some nitrilimines which were generated in situ afforded the new pyrazoles. The regiochemistry and reactivity of these reactions has been investigated on the basis of density functional theory （DFT）-based reactivity indexes and activation energy calculations. The theoretical 13C NMR chemical shifts of the cycloadducts which were obtained by GIAO method were comparable with the observed values.

关键词： regioselectivity cycloaddition density functional calculations

Synthesis of Pyrazolo[3,4-d]pyrimidin-4-ones Catalyzed by Brensted-acidic Ionic Liquids as Highly Efficient and Reusable Catalysts

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Chinese Journal of Chemistry 2011年第11期29卷 2421-2426页

作者： Tavakoli-Hoseini, Niloofar Moloudi, Raheleh davoodnia, abolghasem Shaker, Mohammad Department of Chemistry Mashhad Branch Islamic Azad University Mashhad Iran

A convenient and efficient method for the synthesis of pyrazolo[3,4-d]pyrimidin-4-ones via heterocyclization reaction of 5-amino-lH-pyrazole-4-carboxamides with triethyl orthoesters using two BrCnsted-acidic ionic liquids, 3-methyl-l-（4-sulfonic acid）butylimidazolium hydrogen sulfate [MIM＋（CH2）4SO3H][ HSO4 ] or N-（4-sulfonic acid）butyl triethylammonium hydrogen sulfate [Et3N＋（CH2）4SO3H][ HSO4 ], as efficient homogeneous catalysts under solvent-free conditions is described.

关键词： homogeneous catalysis ionic liquids pyrazolo[3,4-d]pyrimidin-4-ones solvent-free condition triethyl orthoesters

SO3H-Functionalized Ionic Liquids： Green, Efficient and Reusable Catalysts for the Facile Dehydration of Aldoximes into Nitriles

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Chinese Journal of Chemistry 2011年第5期29卷 978-982页

作者： davoodnia abolghasem Khojastehnezhad Amir Bakavoli Mehdi Tavakoli-Hoseini Niloofar Department of Chemistry Faculty of Sciences Mashhad Branch Islamic Azad University Mashhad Iran

Easily synthesized aldoximes have been converted to the corresponding nitriles under very mild conditions by a simple reaction using two halogen-free SO3H-functionalized ionic liquids, 3-methyl-l-（4-sulfonic acid）butylimidazolium hydrogen sulfate [MIM（CH2）aSO3H][HSO4] and 1-（4-sulfonic acid）butylpyridinium hydrogen sulfate [PY（CH2）4SO3H][HSO4], as catalyst and reaction medium without any additional organic solvent. The method was equally effective for aromatic aldoximes bearing electron-donating and electron-withdrawing substituents. Taking into account environmental and economical consideration, the protocol presented here has the merits of environmentally friendly, simple operation, easy work-up and very good yields. The catalysts could be recycled and reused for several times without noticeably decreasing in their catalytic activities.

关键词： ionic liquid aldoxime nitrile dehydration

Keplerate巨型纳米多孔聚氧钼酸盐作为可重复使用催化剂用于合成1,2,4,5-四取代咪唑(英文)

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催化学报 2014年第10期35卷 1761-1767页

作者： Ahmad Nakhaei abolghasem davoodnia Department of Chemistry Mashhad Branch Islamic Azad University

The Keplerate‐type giant nanoporous isopolyoxomolybdate (NH4)42[MoVI72MoV60O372‐(CH3COO)30(H2O)72], denoted {Mo132}, has been used as a catalyst for the synthesis of1,2,4,5‐tetrasubstituted imidazoles by the one‐pot, four‐component thermal reaction of benzil with aromatic aldehydes, primary amines, and ammonium acetate under solvent‐free conditions. The catalyst was prepared according to a previously published literature procedure using inexpensive and readily available starting materials, and subsequently characterized by FT‐IR, UV and X‐ray diffraction spectroscopy, as well as microanalysis. The results showed that {Mo132} exhibited high catalytic activity towards the synthesis of 1,2,4,5‐tetrasubstituted imidazoles, with the desired products being formed in good to high yields. Furthermore, the catalyst was recyclable and could be reused at least three times without any discernible loss in its catalytic activity. Overall, this new catalytic method for the synthesis of 1,2,4,5‐tetrasubstituted imidazoles provides rapid access to the desired compounds following a simple work‐up procedure, and avoids the use of harmful organic solvents. This method therefore represents a significant improvement over the methods currently available for the synthesis of tetrasubstituted imidazoles.

关键词：取代咪唑合成方法可重复使用纳米多孔催化剂 e型应用催化活性

微波辅助溶胶-凝胶法合成MgO纳米粒子及其催化合成Hantzsch1,4-二氢吡啶性能(英文)

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催化学报 2012年第9期33卷 1502-1507页

作者： Hakimeh MIRZAEI abolghasem davoodnia Department of Chemistry Mashhad BranchIslamic Azad University

A microwave-assisted sol-gel method was employed for the preparetion of nano-sized MgO particles using Mg(NO 3)2·6H2O as precursor and deionized water as *** sample calcined at 500℃ had a high specific surface area of 243.2m2/g and particles sizes from *** comparison,MgO nanoparticles were also synthesized without microwave irradiation.X-ray diffraction (XRD) characterization showed the formation of smaller particles after microwave *** structure and morphology of the MgO particles were analyzed by N2 adsorption-desorption,XRD,scanning electron microscopy,and transmission electron *** catalytic behavior was studied with the one-pot synthesis of Hantzsch1,4-dihydropyridines from the reaction of aromatic aldehydes,ethyl acetoacetate,and ammonium *** MgO nanoparticles have high catalytic activity and gave the desired products in good to high *** catalyst can be easily recovered by filtration and was used at least three times with only a slight reduction in its catalytic activity.

关键词： magnesium oxide microwave-assisted sol-gel method nanoparticle Hantzsch 1,4-dihydropyridine

无溶剂条件下可重复使用的担载的酸性离子液体催化剂高效催化酮和芳香醛选择性Cross-Aldol缩合反应(英文)

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催化学报 2012年第12期33卷 1950-1957页

作者： abolghasem davoodnia Ghazaleh YASSAGHI Department of Chemistry Mashhad BranchIslamic Azad University

A newly prepared catalyst consisting of acidic ionic liquid 1-(4-sulfonic acid)butylpyridinium hydrogen sulfate supported on silica was used to catalyze the cross-aldol condensation of ketones with aromatic aldehydes under solvent-free conditions. The highly active and selective catalyst gave good to excellent yields of the desired cross-aldol products without the occurrence of any self-condensation reactions. Reaction times were short, the procedure and work-up were simple, and no volatile or hazardous organic solvents were necessary. Moreover, the catalyst could be reused at least four times with only a slight reduction in activity.

关键词：化学燃烧原理催化

Silica Gel-Supported Polyphosphoric Acid （PPA/SiO2）： An Efficient and Reusable Heterogeneous Catalyst for Facile Synthesis of 14-Aryl-14H-dibenzo[aj]xanthenes under Solvent-free Conditions

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Chinese Journal of Chemistry 2011年第2期29卷 297-302页

作者： Khojastehnezhad Amir davoodnia abolghasem Bakavoli Mehdi Tavakoli-Hoseini Niloofar Zeinali-Dastmalbaf Mohsen Department of Chemistry Faculty of Sciences Islamic Azad University Mashhad Branch Mashhad Iran

A simple, efficient and green method for the synthesis of 14-aryl-14H-dibenzo[aj]xanthenes by a one-pot condensation reaction of β-naphthol and aryl aldehydes using silica gel-supported polyphosphoric acid （PPA/SiO2）, an effective and reusable catalyst, under solvent-free conditions is described. The present methodology offers several advantages, such as a simple procedure with an easy work-up, short reaction times, high yields, and the absence of any volatile and hazardous organic solvents.

关键词： 14-Aryl-14H-dibenzo[a,j]xanthenes PPA/SiO2 heterogeneous catalysis green chemistry solvent-flee conditions