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21.
Mahboubeh Rostami Ahmad R. Khosropour Valiollah Mirkhani Iraj Mohammadpoor-Baltork Majid Moghadam Shahram Tangestaninejad 《Comptes Rendus Chimie》2011,14(10):869-877
Di[1,6-bis(3-methylimidazolium-1-yl)hexane] decatungstate dihydrate ([C6(MIm)2]2W10O32. 2H2O) as a new family of polyoxometalate-based dicationic ionic liquids (POM-DIL) is synthesized and employed as a novel and powerful heterogeneous catalyst in the synthesis of 4-arylidene-2-phenyl-5(4)-oxazolones (azlactones) under ultrasound-assisted solvent-free condition. On the basis of the results, the products were obtained in excellent yields under mild condition. Utilization of easy work-up and purification make it very interesting from an economic perspective. Moreover, a recycling study confirmed that the catalyst can be reused multiple times without significant loss of its activity. 相似文献
22.
Iraj Mohammadpoor‐Baltork Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Zohre Eskandari 《Journal of heterocyclic chemistry》2011,48(2):479-483
An efficient method for the selective synthesis of 2‐substituted oxazines and tetrahydropyrimidines by the reaction of arylnitriles with 3‐amino‐1‐propanol and 1,3‐diaminopropane in the presence of montmorillonite K‐10 and KSF as inexpensive, environmentally benign, and reusable catalysts under classical heating conditions and microwave irradiation is reported. J. Heterocyclic Chem., (2011). 相似文献
23.
Oxidative deprotection of a variety of trimethylsilyl ethers were performed by Fe(NO3)3.9H2O in the presence of H3PMo12O40.xH2O as catalyst at room temperature in good to high yields under solvent‐free conditions. 相似文献
24.
Majid Moghadam Iraj Mohammadpoor-Baltork Valiollah Mirkhani Shahram Tangestaninejad Mohammad Abdollahi-Alibeik Behrooz H. Yousefi Hadi Kargar 《Monatshefte für Chemie / Chemical Monthly》2007,33(3):579-583
Small assemblies of 2-imidazolines and bisimidazolines from appropriate nitriles and ethylenediamine with catalytic amounts
of P2S5 employing a microwave assisted protocol were prepared. Sonication of this system also led to successful synthesis of 2-imidazolines
and bisimidazolines. Another advantage of these systems is the ability to carry out large scale reactions. 相似文献
25.
Iraj Lalezari Abbas Shafiee Shahnaz Sadeghi-Milani 《Journal of heterocyclic chemistry》1979,16(7):1405-1407
A series of 4-aryl (or heteroeyclic)-3-buten-2-one semicarbazones as well as 6-phenyl-3,5-hexadien-2-one semicarbazone were reacted with selenium dioxide to give the corresponding 4-substituted vinyl and 4-phenyl-1,2-butadienyl-1,2,3-selenadiazoles. The selenadiazoles were converted to the corresponding 1,4-diselenafulvenes. Pyrolysis of 4-styryl-1,2,3-selenadiazole gave 2,5-distyrylselenophene. 相似文献
26.
Tangestaninejad S Moghadam M Mirkhani V Mohammadpoor-Baltork I Salavati H 《Ultrasonics sonochemistry》2008,15(5):815-822
Na5PV2Mo10O40 supported on nanoporous anatase TiO2 particles, TiO2–PVMo, was used as an efficient photocatalyst for photocatalytic degradation of different dyes by visible light using oxygen as oxidant. This catalyst showed a good catalytic activity in the sonocatalytic and sonophotocatalytic decomposition of different dyes in aqueous solutions. The TiO2–PVMo composite showed higher photocatalytic and sonocatalytic activity than pure polyoxometalate or pure TiO2. 相似文献
27.
Mona Ghoorchibeigi Kambiz Larijani Parviz A. Azar Karim Zare Iraj Mehregan 《Journal of heterocyclic chemistry》2020,57(10):3612-3621
The preparation of pyrazolo pyrimidinone derivatives was performed by using five component reactions of phthalaldehyde, cyanomethylamine, electron deficient acetylenic compounds, isocyanate, hydrazine, and catalytic amounts of ZnO/Fe3O4-magnetic nanoparticles as a high performance catalyst under ultrasonic conditions at ambient temperature in aquause media at room temperature. It should be mentioned that this catalyst was prepared using Spinacia oleracea water extract. In addition, for investigation of antioxidant ability, radical trapping by DPPH and reducing power of ferric ion experiments was performed. As a result, synthesized compounds show excellent radical trapping by DPPH and good reducing ability of ferric ion. The current procedure has the benefits for instance excellent yield of reaction, green media, and easy separation of product and catalyst. 相似文献
28.
Teimuri-Mofrad Reza Ahadzadeh Iraj Gholamhosseini-Nazari Mahdi Esmati Somayeh Shahrisa Aziz 《Research on Chemical Intermediates》2018,44(4):2913-2927
Research on Chemical Intermediates - In this research, for the first time, aminonaphthol derivatives were introduced as efficient corrosion inhibitors. A linear polarization method was employed to... 相似文献
29.
Iraj Salimikia Rouhollah Heydari Fatemeh Yazdankhah 《Journal of the Iranian Chemical Society》2018,15(7):1593-1601
A solid-phase microextraction fiber was prepared by polyaniline/graphene oxide nanocomposite as sorbent on the surface of a platinized stainless steel wire using electrospinning technique. The nanocomposite structure was characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. The polyaniline/graphene oxide nanocomposite fiber was used for the determination of nicotine from tobacco samples using headspace solid-phase microextraction method and gas chromatography–flame ionization detection. Influential experimental variables on the extraction efficiency of nicotine, such as extraction time and temperature, humidity and desorption conditions, were evaluated and optimized. Under the optimal experimental conditions? the limit of detection, linear dynamic range, intraday and inter-days precisions were found to be 0.01 μg g?1, 0.05–700 µg g?1 (R2?=?0.996), 6.9 and 8.1%, respectively. Comparison of the polyaniline/graphene oxide nanocomposite sorbent with polyaniline and commercial fibers shows longer durability, larger capacity and higher extraction efficiency. The polyaniline/graphene oxide nanocomposite fiber was successfully applied for the determination of nicotine in tobacco samples. 相似文献
30.
Bahman Kalantari Iraj Kalantari Rahim Zaare-Nahandi 《Journal of Computational and Applied Mathematics》1997,80(2):233-226
Let p(x) be a polynomial of degree n?2 with coefficients in a subfield K of the complex numbers. For each natural number m?2, let Lm(x) be the m×m lower triangular matrix whose diagonal entries are p(x) and for each j=1,…,m−1, its jth subdiagonal entries are . For i=1,2, let Lmi)(x) be the matrix obtained from Lm(x) by deleting its first i rows and its last i columns. L1(1)(x)≡1. Then, the function Bm(x)=x−p(x) defines a fixed-point iteration function having mth order convergence rate for simple roots of p(x). For m=2 and 3, Bm(x) coincides with Newton's and Halley's, respectively. The function Bm(x) is a member of S(m,m+n−2), where for any M?m, S(m,M) is the set of all rational iteration functions g(x) ∈ K(x) such that for all roots θ of p(x), then g(x)=θ+∑i=mMγi(x)(θ−x)i, with γi(x) ∈ K(x) and well-defined at any simple root θ. Given g ∈ S(m,M), and a simple root θ of p(x), gi(θ)=0, i=1, …, m−1 and the asymptotic constant of convergence of the corresponding fixed-point iteration is . For Bm(x) we obtain . If all roots of p(x) are simple, Bm(x) is the unique member of S(m,m + n − 2). By making use of the identity , we arrive at two recursive formulas for constructing iteration functions within the S(m,M) family. In particular, the family of Bm(x) can be generated using one of these formulas. Moreover, the other formula gives a simple scheme for constructing a family of iteration functions credited to Euler as well as Schröder, whose mth order member belongs to S(m,mn), m>2. The iteration functions within S(m,M) can be extended to any arbitrary smooth function f, with the uniform replacement of p(j) with f(j) in g as well as in γm(θ). 相似文献