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排序方式: 共有183条查询结果,搜索用时 902 毫秒
61.
Mahboubeh Rostami Ahmad R. Khosropour Valiollah Mirkhani Iraj Mohammadpoor-Baltork Majid Moghadam Shahram Tangestaninejad 《Journal of the Iranian Chemical Society》2014,11(5):1493-1501
Di[1,6-bis(3-methylimidazolium-1-yl)hexane] decatangstate ([C6(MIm)2]2W10O32) was found to be a novel, powerful and effective catalyst for the preparation of N-benzoylglycine carbamides as derivatives of AT-130 via one-pot multicomponent reaction performed under microwave irradiations. The products were obtained in high to excellent yields, thus providing a unique strategy to the large-scale synthesis of these compounds. 相似文献
62.
Chloromethylated polystyrene supported copper (II) bis–thiazole complex: Preparation,characterization and its application as a heterogeneous catalyst for chemoselective and homoselective synthesis of aryl azides 下载免费PDF全文
Zahra Dehbanipour Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Iraj Mohammadpoor‐Baltork 《应用有机金属化学》2018,32(9)
This work deals the synthesis of aryl azides catalyzed by heterogeneous copper (II) complex of 3,5–bis (2–benzothiazolyl) pyridine, [Cu (II)(BTP)(OTf)2], immobilized on chloromethylated polystyrene, [Cu (II)(BTP)(OTf)2]@CMP. The prepared catalyst was characterized by different analytical techniques such as X‐ray diffraction (XRD), thermogravimetric analysis (TGA), field emission scanning electron microscopy (SEM), energy dispersive X–ray spectroscopy (EDX), elemental analysis, and FT‐IR and UV–Vis spectroscopic methods. This catalytic system showed excellent activity in the synthesis of aryl azides by the reaction of aryl halides with sodium azide in the presence of catalytic amounts of [Cu (II)(BTP)(OTf)2]@CMP. Moreover, this unique catalyst could be recovered easily and reused several times without any considerable loss of its catalytic activity. 相似文献
63.
Dodecatungstocobaltate heteropolyanion encapsulation into MIL‐101(Cr) metal–organic framework scaffold provides a highly efficient heterogeneous catalyst for methanolysis of epoxides 下载免费PDF全文
Afsaneh Marandi Shahram Tangestaninejad Majid Moghadam Valiollah Mirkhani Adam Mechler Iraj Mohammadpoor‐Baltork Farnaz Zadehahmadi 《应用有机金属化学》2018,32(2)
A heterogeneous catalyst was synthesized by encapsulation of a Keggin‐type heteropolytungstate, potassium dodecatungstocobaltate trihydrate, K5[CoW12O40]·(Co‐POM), into chromium(III) terephthalate (MIL‐101). Encapsulation was achieved via a ‘build bottle around ship’ strategy in aqueous media, following a hydrothermal method. The structure of the resulting crystalline solid was characterized using X‐ray diffraction, correlated with Fourier transform infrared and UV–visible spectroscopy. The metal content was analysed using optical emission spectroscopy. Transmission electron microscopy was used to measure particle size and N2 adsorption in a Brunauer–Emmett–Teller instrument to characterize the specific surface area. The catalytic activity was investigated using methanolysis of epoxides under mild conditions as a test reaction. The turnover frequency of the heterogeneous Co‐POM@MIL‐101 catalyst was more than 20 times higher than that of the homogeneous Co‐POM catalyst. The Co‐POM@MIL‐101 catalyst was reused several times with negligible leaching of Co‐POM and with no considerable loss of its initial efficiency. The simplicity of preparation, extraordinary stability and high reactivity make Co‐POM@MIL‐101 an exceptional catalytic matrix that is easily separable from reaction media. 相似文献
64.
In this work, a penalization method is discussed in the context of vortex methods for incompressible flows around complex geometries. In particular, we illustrate the method in two cases: the flow around a rotating blade for Reynolds numbers 1000 and 10,000 and the flow past a semi‐circular body consisting of a porous layer surrounding a rigid body at Reynolds numbers 550 and 3000. In the latter example, the results are interpreted in terms of control strategy. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
65.
Mehdi Shafiee Ahmad Reza Khosropour Iraj Mohammadpoor-Baltork Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Hamid Reza Khavasi 《Molecular diversity》2012,16(4):727-735
An expeditious, straightforward and efficient synthesis of diversely naphtho[1,2-e][1,3]oxazines via one-pot condensation reaction of ??- naphthol, 3-amino-5-methylisoxazole and arylaldehydes catalyzed by bismuth(III) trifluoromethanesulfonate is described. The reaction preferentially afforded 1,3-trans oxazines. 相似文献
66.
A simple, efficient, and mild method for selective bromination of some activated aromatic compounds using potassium bromide in the presence of benzyltriphenylphosphonium peroxodisulfate in nonaqueous solution is reported. The results obtained revealed good to excellent selectivity between ortho and para positions of phenols and methoxyarenes. 相似文献
67.
Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Iraj Mohammadpoor-Baltork Saeedeh Gorjipoor Parvin Yazdani 《合成通讯》2013,43(3):552-561
Efficient ring opening of epoxides with aromatic amines catalyzed by ZrO(OTf)2 is reported, and the corresponding β amino (beta-amino acid) alcohols were obtained in high yields in CH3CN as solvent. The reactions were carried out at room temperature and in the presence of only 1.25 mol% of ZrO(OTf)2. This catalyst can be reused several times without loss of its activity. 相似文献
68.
Mohammad M. Khodaei Parvin Ghanbary Iraj Mohammadpoor‐Baltork Hamid R. Memarian Ahmad R. Khosropour Kobra Nikoofar 《Journal of heterocyclic chemistry》2008,45(2):377-381
A new, facile, efficient, “green” and chemoselective procedure for the synthesis of indole derivatives has been developed with pulverization‐activation method catalyzed by Bi(NO3)3·5H2O (PAMC‐ Bi(NO3)3·5H2O) through grinding of indoles with aldehydes or Michael acceptors in the presence of catalytic amounts of Bi(NO3)3·5H2O under solvent‐free conditions. 相似文献
69.
Base decomposition of 4‐(substituted phenyl)‐1,2,3‐selenadiazoles at room temperature resulted in 2‐(substituted phenyl)‐ethynylselenolate anions, which were immediately reacted with bromoacetonitrile to give a series of 2‐(substituted phenyl)ethynylselanylacetonitriles. 相似文献
70.
Elham Morteza Payam Moaveni Iraj Alahdadi Mohammad-Reza Bihamta Tahereh Hasanloo 《Natural product research》2015,29(7):663-666
In order to investigate the composition of borage (Borago officinalis L.) seed oil, this research was performed under the field conditions at Shahriyar and Garmsar zones, Iran during the 2012 planting year. The oil yield of borage was 31.46% and 33.7% at Shahriyar and Garmsar zone, respectively, and nine and eight fatty acids were identified in the seed oil of borage at Shahriyar and Garmsar, respectively – palmitic, linoleic, stearic and γ-linolenic acids were dominant in the seed oil of borage from both zones. Unsaturated fatty acid content was more than the saturated fatty acids in both zones. The ratio of linoleic acid and α-linolenic acid in the borage cultivated at Shahriyar and Garmsar zones was 2.13 and 2.29. The fatty acid profile of Garmsar borage, oleic and oleic/linoleic acid ratio, increased. Locations with different ecological conditions resulted in changes in both seed oil content and fatty acid profile of borage. 相似文献