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51.
Khalil Tabatabaeian Manouchehr Mamaghani Nosratollah Mahmoodi Alireza Khorshidi 《合成通讯》2013,43(11):1677-1684
Diastereoselective conjugate 1,4-addition of indoles to α,β-unsaturated carbonyl compounds (hormone steroids) using Ru(III) as catalyst is reported. It was found that RuCl3·nH2O catalyzes the Michael addition of indoles to hormone steroids, providing new 3-alkylated derivatives in good to excellent yields. 相似文献
52.
Nuran Asmafiliz Zeynel Kılıç Aslı Öztürk Yasemin Süzen Tuncer Hökelek Leyla Açık 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1723-1742
Abstract The condensation reactions of hexachlorocyclotriphosphazene (N3P3Cl6) with mono (1 and 2) and bisferrocenyldiamines (3–5 and 7) resulted in the formation of tetrachloro mono- (8 and 9) and bisferrocenylspirocyclotriphosphazenes (10–13). In addition the tetramorpholino mono- (8a and 9a) and bisferrocenylphosphazenes (10a–12a) were obtained from the reactions of the corresponding tetrachlorophosphazenes (8–12) with excess morpholine. The structures of all the phosphazenes were determined using FTIR, MS, 1H, 13C, and 31P NMR and 2-dimensional NMR techniques. The structures of 9a and 13 were determined by single crystal X-ray diffraction techniques. Cyclic voltammetric investigations of compounds 8a, 9a, and 11a revealed that ferrocene redox centers undergo reversible oxidation. These ferrocenylphosphazenes appear to be quite robust electrochemically. Interactions between the compounds 8a, 9a, 11a, and 12a and pBR322 plasmid DNA were investigated by agarose gel electrophoresis. [Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional text and figures.] 相似文献
53.
NaBH4/Ac2O/DOWEX(R)50WX4: A Convenient System for Fast Preparation of gem‐Diacetates from Aldehydes
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Reductive‐acylalation of aldehydes has been carried out by NaBH4/Ac2O/DOWEX(R)50WX4 system. A variety of aldehydes (1 mmol) have been reacted with Ac2O (0.5 mL) and NaBH4 (1 mmol) in the presence of DOWEX(R)50WX4 (0.5 g) for the preparation of their corresponding acylals within 1 min at room temperature with excellent yields of the products (90‐95%). Ketones do not react with this system. 相似文献
54.
Moona Mohsenimehr Manouchehr Mamaghani Farhad Shirini Mehdi Sheykhan Fatemeh Azimian Moghaddam 《中国化学快报》2014,25(10):1387-1391
Novel pyrido[2,3-d]pyrimidine derivatives were synthesized through a one-pot three-component approach using HAp-encapsulated-γ-Fe2O3[γ-Fe2O3@HAp-SO3H]catalyzed condensation of 6-arnino-2-(methylthio or ethylthio)pyrimidin-4(3H)-one,Meldrum's acid and aryl aldehydes at 60 ℃ and under solvent-free conditions.In this protocol the use of nanocatalyst provided a green,useful and rapid method to generate the products in short reaction times and excellent yields(88%-94%). 相似文献
55.
An efficient and convenient method for the synthesis of 1,4-dihydropyridines from β-dicarbonyl compounds, aldehydes, and ammonium acetate and the synthesis of fused 1,4-dihydropyridines from dimedone in the presence of Preyssler heteropolyacid catalyst are reported under reflux conditions with good to excellent yields. Preyssler heteropolyacid catalyst is easily prepared, stable (up to 300 °C), reusable, efficient, green and inexpensive. 相似文献
56.
Manouchehr Zaker 《Discrete Applied Mathematics》2007,155(18):2567-2572
The Grundy (or First-Fit) chromatic number of a graph G is the maximum number of colors used by the First-Fit coloring of the graph G. In this paper we give upper bounds for the Grundy number of graphs in terms of vertex degrees, girth, clique partition number and for the line graphs. Next we show that if the Grundy number of a graph is large enough then the graph contains a subgraph of prescribed large girth and Grundy number. 相似文献
57.
-Azidophenyl -alkyl ketones in ethanolic potassium hydroxide at room temperature cyclise in high yield to 2,2-dialkylindoxyls. 相似文献
58.
An Expedient Synthesis of Novel Derivatives of Pyrido[2,3‐d]pyrimidines Using Magnetically Supported ZrO2 Nanocatalyst
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Leila Kheirkhah Manouchehr Mamaghani Nosrat Ollah Mahmoodi Asieh Yahyazadeh Abdollah Fallah Shojaei Yaseman Rostamli 《中国化学会会志》2016,63(5):410-416
An efficient synthesis of pyrido[2,3‐d]pyrimidine derivatives via one‐pot multicomponent reactions of 6‐amino‐2‐(alkylthio)pyrimidin‐4(3H)‐one, 3‐cyanoacetylindole and arylaldehydes using [Fe3O4@ZrO2] as magnetically recyclable nanocatalyst is reported. This protocol furnished the desired products in good to excellent yields (70–93 %) and lower reaction times. The catalyst could be easily and efficiently separated from the final product solution by an external magnet and be reused in 5 consecutive runs without any significant activity decrease. 相似文献
59.
Basic Ionic Liquid as Catalyst and Reaction Media for the One‐pot Three‐component Regioselective Synthesis of Various Thiazol‐2‐imine Derivatives
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Jafar Abbasi Shiran Asieh Yahyazadeh Bohari M. Yamin Manouchehr Mamaghani Jalal Albadi 《Journal of heterocyclic chemistry》2016,53(4):1009-1016
Thiazol‐2‐imine derivatives were synthesized in an easy and efficient route from the regioselective one‐pot three‐component reaction of aryl amine, alkylisothiocyanate, and various α‐haloketones in [omim][OH] basic ionic liquid. Recyclable reaction media, catalyst free, and short reaction times are the main advantages of this protocol. This method produces the products at room temperature in excellent yields (68–96%). Furthermore, the target compound 6b was determined by X‐ray crystallographic analysis. 相似文献
60.
Seyed Heidar Mirjahanmardi Faramarz Afshar Taromi Roya Zahedi Mehdi Nekoomanesh Haghighi Roghayeh Jamjah Gholamali Jafari Asl 《Polymer Science Series B》2016,58(6):619-628
The multi-ether compounds with different numbers of methoxy groups containing 1,3-dimethoxy-2,2-bis(methoxymethyl)propane and 1-methoxy-2,2-bis(methoxymethyl)butane were synthesized using the Williamson reaction from pentaerythritol and 1,1,1-tris(hydroxymethyl)propane, respectively, in the presence of sodium hydride and methyl iodide in tetrahydrofuran and they were characterized by 1H NMR, 13C NMR, and FTIR spectroscopy. These compounds were employed as external donors in the polymerization of propylene using the industrial Ziegler-Natta catalyst. A commercial spherical MgCl2-supported Ziegler-Natta catalyst containing diisobutyl phthalate as the internal donor was used for the polymerization of propylene. The role of ether compounds and industrial alkoxysilanes on the properties of polypropylene were studied using the xylene solubility method, melt flow index, gel permeation chromatography, scanning electron microscopy, and differential scanning calorimetry. The addition of the electron donors has led to improvements in the activity and selectivity of the Ziegler-Natta catalyst system. 相似文献