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441.
An efficient and direct protocol for the preparation of amidoalkyl naphthols employing a multicomponent, one-pot condensation reaction of β-naphthol, aromatic aldehydes, and amides (acetamide, benzamide, and urea) in the presence of tetrakis(acetonitrile)copper(I) hexafluorophosphate [Cu(CH3CN)4PF6] under solvent-free conditions at 80 °C is described. Good yields, short reaction time, and easy workup are advantages of this procedure. 相似文献
442.
This review highlights the methods used for the synthesis of 3-oxo-N-(pyridin-2-yl)butanamide compounds. The reactivity and synthetic importance are investigated. In this context, recent progress in the synthesis and use of 3-oxo-N-(pyridin-2-yl)butanamide as precursors for heterocyclic compounds is reviewed. The synthetic routes for preparation of 3-oxo-N-(pyridin-2-yl)butanamide are based on the reaction of diketene with aromatic primary amine and reaction of 2-aminopyridine with β-keto-t-butylthioester or ethylacetoacetate. The bibliography includes 73 references. 相似文献
443.
Abbas Ali Esmaeili Hamid VesalipoorRahele Hosseinabadi Alireza Fakhari ZavarehMohammad Ali Naseri Ebrahim Ghiamati 《Tetrahedron letters》2011,52(38):4865-4867
The zwitterions generated from pyridine and dialkyl acetylenedicarboxylate (DAAD) reacted with benzofuran-2,3-diones to form highly substituted spiro pyrido[2,1-b][1,3]oxazines in good to high yields without using a catalyst. 相似文献
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Natural gas viscosity is an important parameter in many gas and petroleum engineering calculations.This study presents a new empirical model for quickly calculating the natural gas viscosity.The model was derived from 4089 experimental viscosity data with varieties ranging from 0.01 to 21,and 1 to 3 of pseudo reduced pressure and temperature,respectively.The accuracy of this new empirical correlation has been compared with commonly used empirical models,including Lee et al.,Heidaryan et al.,Carr et al.,and Adel Elsharkawy correlations.The comparison indicates that this new empirical model can predict viscosity of natural gas with average absolute relative deviation percentage AARD (%) of 2.173. 相似文献
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Mohammad Hossein Tavakoli Talaye Arjmand Abasi Ebrahim Haji Ali 《Crystal Research and Technology》2013,48(3):130-137
KCl alkali halide crystal with different nanodiamond impurity was grown by Czochralski method. X‐Ray diffraction of the outcome samples reveals that they are still single crystal. Also crystal hardness observation reveals that the hardness of KCl single crystal has been increased by adding different percentage of nanodiamond impurity. In addition, the study of FTIR spectrums of the pure and doped crystals represents that the KCl optical properties has not changed. 相似文献