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Abolghasem Davoodnia Amir Khojastehnezhad Mehdi Bakavoli Niloofar Tavakoli‐Hoseini 《中国化学》2011,29(5):978-982
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‐1‐(4‐sulfonic acid)butylimi‐ dazolium hydrogen sulfate [MIM(CH2)4SO3H][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. 相似文献
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Russian Journal of Organic Chemistry - Two fluorescent heterocyclic ligands were obtained by reduction of imidazo[4,5-e][2,1]benzoxazole derivatives with Fe/HCl. New fluorescent nickel(II)... 相似文献
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Abolghasem Davoodnia Mohammad Rahimizadeh Hoda Atapour‐Mashhad Niloofar Tavakoli‐Hoseini 《Heteroatom Chemistry》2009,20(6):346-349
The reaction of 2‐amino‐4,5‐dimethyl‐ thiophene‐3‐carboxamide with iso(and isothio) cyanates for the synthesis of thieno[2,3‐d]pyrimidines has been investigated. The reactions under microwave irradiation in the presence of N,N‐dimethyl acetamide as solvent gave 5,6‐dimethylthieno[2,3‐d]pyrimidine‐2,4(1H,3H)‐dione, 5,6‐dimethyl‐2‐thioxo‐2,3‐dihy‐ drothieno[2,3‐d]pyrimidin‐4(1H)‐one, and 2‐aryla‐ mino‐5,6‐dimethylthieno[2,3‐d]pyrimidin‐4(3H)‐one derivatives. These reactions probably proceed through intermediates 4,5‐dimethyl‐2‐substitutedcarbamoth‐ ioylaminothiophene‐3‐carboxamides. Two of these intermediates were isolated. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:346–349, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20557 相似文献
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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. 相似文献
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Dorostkar-Ahmadi N Bakavoli M Moeinpour F Davoodnia A 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,79(5):1375-1380
Reaction of 4-nitrobenzonitrile oxide (2) which was generated in situ with acrylo nitrile (3), methyl methacrylate (4) and allyl bromide (5) as dipolarphile afforded the new 7a, 8a and 9a compounds respectively. Reactivity and regiochemistry of these reactions were investigated using activation energy calculations and density functional theory (DFT)-based reactivity indexes. The theoretical 13C NMR chemical shifts of the cycloadducts which were obtained by GIAO method were comparable with the observed values. 相似文献
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M. Roshani A. Davoodnia M. Sh. Hedayat M. Bakavoli 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1153-1157
New derivatives of 2-substituted pyrido[3′,2′:4,5]thieno[3,2-d]pyri-midin-4(3H) ones and 3-substituted pyrido[3′,2′:4,5]thieno[3,2-d]pyri-midin-2,4(1H,3H) diones have been prepared by base catalyzed cyclocondensation of ethyl-3-aminothieno[3,2-b]pyridine-2-carboxylate with aryl nitriles and aryl- or alkyl isocyanates respectively. 相似文献
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An efficient, environmentally friendly procedure for the synthesis of amidoalkyl naphthols through the one‐pot, three‐component reaction of β‐naphthol, aryl aldehydes, and acetamide in the presence of a carbon‐based solid acid under thermal solvent‐free conditions is described. The beneficial fea-tures of this new synthetic approach include short reaction time, high yields, clean reaction profiles, and a simple work‐up procedure. Furthermore, the catalyst can be readily recycled and reused four times without obvious significant loss of activity. The structure of the catalyst was confirmed by Fourier transform infrared spectroscopy, N2 adsorption/desorption analysis, and X‐ray diffraction. 相似文献
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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. 相似文献