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1.
Aluminium dodecyl sulfate trihydrate [Al(DS)3].3H2O is easily prepared and can be used as a Lewis acid surfactant catalyst in water to conduct the highly efficient Michael addition of indoles and pyrrole to alpha,beta-unsaturated electron-deficient compounds at room temperature. 相似文献
2.
[11C]Carbon monoxide at low concentrations, aryl halides and amines were used in the palladium-mediated synthesis of twenty 11C-amides. In the study several approaches to improve the radiochemical yield were explored. Eight of the selected amides were prepared by in situ activation of the amines using lithium bis(trimethylsilyl)amide and the radiochemical yields of these reactions were improved compared to utilising a previous reported method. In the synthesis of 1-[carbonyl-11C]benzoyl-3-methyl-1H-indole (11) from 3-methyl-1H-indole (25), the corresponding organotin-amine was prepared prior to the acylation reaction. In a typical experiment, N-(4-hydroxyphenyl)[carbonyl-11C]acetamide (5) was prepared in 15% radiochemical yield using 4-aminophenol (20) but the yield increased to 63% when the amine was activated by lithium bis(trimethylsilyl)amide. 相似文献
3.
Farhad Sattari Soghra Mirershadi 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(10):227
In this paper the transmission and the shot noise properties through the strain-inducedgraphene superlattices are studied. It is found that for the zigzag direction strain theFano factor shows a peak at new Dirac-like point and the position of the new Dirac pointvaries against the strain. Also, Fano factor has an oscillatory behavior with respect tostrain strength and the oscillation period decreases by increasing the number of barriers.However, for the armchair direction strain the transmission can be blocked by the electricbarrier and the Fano factor approaches 1, this is different from the zigzag directionstrain. 相似文献
4.
Nanocrystalline TiO2-HClO4,as newly reported catalyst,has been used as an efficient and reusable catalyst for the chemoselective N-Boc protection of amines.The clean,mild acidity condition, quantitative yields of products,short reaction time and low reaction temperature are attractive features of this reaction.In practice,this method is a combination of a satisfactory synthesis and more significantly easy product isolation and purification. 相似文献
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Farhad Shirini Manouchehr Mamaghani Seyyed Vahid Atghia 《Journal of the Iranian Chemical Society》2013,10(3):415-420
Nanoporous Na+-montmorillonite sulfonic acid was found to be an efficient and green catalyst for the synthesis of various 14-aryl-14H-dibenzo[a,j]xanthenes and 1,8-dioxo-dodecahydroxanthene derivatives by the reaction of aldehydes with 2-naphthol and 1,3-cyclohexanedione, respectively. This novel synthetic method has the advantages of high yields, short reaction times and recyclability of the catalyst, simplicity and easy workup compared to the conventional methods reported in the literature. 相似文献
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Smailii Parisa Pakroo Raziye Mohammadkhani Ramin Jafarian Vahab Kabiri Esfahani Farhad Hassani Leila 《Journal of the Iranian Chemical Society》2020,17(1):127-134
Journal of the Iranian Chemical Society - Herein, we investigated the interaction of cisplatin loaded on GO (GO@CDDP) with two regulatory sequences, BRCA1 and BRCA2, synthesized from ssDNA based on... 相似文献
10.
Farhad Shirini Somayeh Akbari-DadamahalehAli Mohammad-Khah 《Comptes Rendus Chimie》2013,16(10):945-955
Rice-husk-supported FeCl3 nano-particles (FeCl3–RiH) were prepared and used as an environmentally friendly catalyst in the synthesis of β-amino carbonyl compounds, 1,8-dioxo-octahydro xanthenes, and bis-indolyl methanes from simple and readily available precursor molecules. 相似文献