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121.
Kioumars Aghapoor Hossein Reza Darabi Kourosh Tabar-Heydar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1183-1187
On the benzyl system, bearing various functional groups, have been carried out the Willgerodt-Kindler reaction to obtain thiobenzmorpholide ( 1 ). The reactions, under solvent-free conditions, were performed in both classical (reflux, room temperature) and nonclassical (microwave) conditions to attempt our elucidation of the reactions pathways. Unlike benzylamine and benzyl mercaptan, benzyl halides give poor result due to the type of amine. The experimental results suggest that the proposed reaction pathway involves the oxidation coupling of benzylic substrates, followed by a thiolation step and an attack of the amine on the thiolated product to give ( 1 ). 相似文献
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Hamid Reza Shaterian Asghar Hosseinian Majid Ghashang Fahimeh Khorami Neda Karimpoor 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2333-2338
An environmentally friendly procedure for the preparation of dihydropyrimidinone derivatives or their sulfur analogues under thermal solvent-free conditions in the presence of aluminium hydrogen sulfate [Al(HSO4)3] and alumina sulfuric acid (Al2O3-SO3H) as heterogeneous catalysts was developed. 相似文献
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Design and characterization of Dendrimer of MNPs as a novel,heterogeneous and reusable nanomagnetic organometallic catalyst for one‐pot synthesis of hydroxyl naphthalene‐1,4‐dione derivatives under solvent‐free conditions 下载免费PDF全文
A novel super acidic magnetic nanoparticle as catalyst was successfully synthesized. The preparation of this dendrimer sulfonic acid functionalized γ‐Fe2O3 magnetic core‐shell silica nanoparticles as a new recoverable and heterogeneous nanocatalyst was described. The new catalyst was characterized using various techniques such as scanning electron microscopy (SEM), energy dispersive spectrum (EDS), and thermo gravimetric synthesis (TGA). Moreover, we have examined the catalytic activity of the catalyst for one‐pot, efficient and facile synthesis of 2‐hydroxy‐1,4‐naphthoquinone derivatives via a three‐component condensation reaction of 2‐hydroxynaphthalene‐1,4‐dione, aromatic aldehydes and aniline derivatives. High yields of products, short reaction times, waste‐free, mild, ambient and solvent‐free reaction conditions are advantages of this protocol. Also, the catalyst can be easily recovered by an external magnetic and reused several times without significant loss of its catalytic activity. 相似文献
126.
Arefeh Dadras M. Reza Naimi‐Jamal Firouz Matloubi Moghaddam Seyed Ebrahim Ayati 《应用有机金属化学》2018,32(2)
Aryl halides and especially inactive aryl chlorides were coupled to benzenoid aromatic rings in a Suzuki–Miyaura coupling reaction in the absence of organic solvents and toxic phosphine ligands. The reaction was catalysed by a recoverable magnetic nanocatalyst, Pd@Fe3O4, in aqueous media. This method is green, and the catalyst is easily removed from the reaction media using an external magnetic field and can be re‐used at least 10 times without any considerable loss in its activity. The catalyst was characterized using scanning and transmission electron microscopies, thermogravimetric analysis, inductively coupled plasma spectroscopy, Fourier transform infrared spectroscopy, CHN analysis, X‐ray diffraction and vibrating sample magnetometry. 相似文献
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The multicomponent condensation of an aryl aldehyde,acetyl chloride,acetonitrile,and enolizable ketone as one-pot synthesis of β-acetamido ketones in high yields was investigated using commercial,non-corrosive,and environmentally benign Keggin and Wells-Dawson heteropolyacid catalysts.The best catalyst was H5PW10V2O40.The methodology used simple experimental conditions,and the short reaction times and high yields indicate it is a useful strategy for the large scale synthesis of β-acetamido ketones. 相似文献
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Zeinab Noroozi Tisseh Minoo Dabiri Mohsen Nobahar Hamid Reza Khavasi Ayoob Bazgir 《Tetrahedron》2012,68(6):1769-1773
An approach for the synthesis of new 5-substituted-tetrazoles via multi-component domino Knoevenagel condensation/1,3 dipolar cycloaddition reaction of carbonyl compounds, malononitrile and sodium azide in water without assistance of any catalyst has been reported. This general protocol provides a wide variety of 5-substituted 1H-tetrazoles in good yields under mild reaction conditions. 相似文献