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1.
那格列奈的合成研究   总被引:2,自引:0,他引:2  
报道了抗糖尿病新药那格列标的全合成及工艺改进。  相似文献   
2.
采用Raney Ni为催化剂,考察了反应温度、压力、时间和溶剂对二亚糠基丙酮加氢制取长链烷烃前驱体催化性能的影响。结果表明,Raney Ni对二亚糠基丙酮具有很好的低温加氢性能,升高反应温度和压力均有利于加氢反应的进行,但过高的温度反而不利于加氢反应。在50℃和2.5 MPa下反应2 h,二亚糠基丙酮转化率达99.5%以上,饱和加氢产物的总选择性达到80.8%。此外,加氢中间产物的变化结果表明,二亚糠基丙酮的双键加氢容易程度为,烯键>呋喃环双键>C=O双键。Raney Ni 在甲醇溶剂中的加氢性能明显高于在四氢呋喃、环己烷或水溶剂中的加氢性能。  相似文献   
3.
Aryl ketones are readily deoxygenated to their corresponding aryl alkanes upon treatment with Raney nickel catalyst in boiling 2-propanol.

Additional information

ACKNOWLEDGMENTS

The authors gratefully acknowledge financial support from the Covenant College Kaleo Center. In addition, we are indebted to the W. R. Grace Company, Chattanooga, for the generous donation of Raney nickel catalyst.  相似文献   
4.
Raney nickel in refluxing 2‐propanol containing a trace of HCl is an effective catalytic system for the reduction of ketones to secondary alcohols.  相似文献   
5.
Aldoximes are readily dehydrated to nitriles with Raney nickel in refluxing 2-propanol.  相似文献   
6.
本文采用XRD、XPS、及H_2—TPD技术对不同Cu/Co比的几个RaneyCu-Co催化剂进行了表征.并与反应醇选择性进行了关联.结果表明:RaneyCu-Co催化剂均由不同Cu/Co比的两个Cu-Co固溶体相组成,还原(H_2,563K,2h)前,表面除有Cu ̄0和Co ̄0外,尚有少量Cu ̄(+1)和显著量的Co ̄(+2)存在,还原后,Cu ̄(+1)几乎消失,Co ̄(+2)仍有一定量存在,在反应温度下(563K),CO和CO_2均能使表面Co ̄0部分氧化,且CO_2氧化能力大于CO,而合成气(H_2/CO=2)表现为还原的性质。三种气氛对Cu ̄0无明显影响。催化剂表面Cu/Co比高于体相Cu/Co比,表面Cu富集显著.RaneyCu-Co催化剂表面有四种吸氢中心:Cu(弱吸氢中心),高配位Co(弱吸氢中心),低配位Co(活化吸氢中心),及强吸氢中心;对不同催化剂,表面低配位Co中心的比例与醇选择性有一致的变化规律。基于上述结果,就CO播入中心进行了讨论。  相似文献   
7.
A Raney-Ag catalyst was prepared by leaching out aluminium from a Raney Ag-Al alloy with NaOH solution. The kinetics of leaching has been investigated in a stirred-batch-reactor at various temperatures by using alloy particles of different sizes. The kinetic model best fitting the experimental results has been determined. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
8.
A general synthetic strategy for the rapid construction of poly(ether imine) dendrons and dendrimers with a nitrogen core, originating from 3-amino-propan-1-ol, is described. A new trifunctional monomer, namely, 3-[bis-(3-hydroxypropyl)amino]propan-1-ol, was used in a divergent synthesis of dendrimers up to the third generation. This method permitted installation of, either alcohol, amine, nitrile, ester or carboxylic acid groups at the peripheries the dendrimers. Cytotoxicity studies on water-soluble carboxylic acid terminated dendrimers were conducted and these studies revealed that poly(ether imine) dendrimers were non-toxic. These results illustrate that poly(ether imine) dendrimers are useful for biological studies.  相似文献   
9.
Structural characteristics and electrocatalytic activity in the methanol oxidation reaction in an alkaline solution of the Raney nickel promoted by a platinum-ruthenium mixture are studied with the aid of methods of scanning electron microscopy, x-ray diffraction microanalysis, BET, and measurements of cyclic voltamograms and polarization curves. Distributions of all components of the system under investigation (Al, Ni, Pt, Ru, O) at the surface of the catalyst, the average size of whose particles amounts to 20–30 μm, are established. It is shown that a number of parameters (composition and quantity of the promoting mixture, temperature and concentration of methanol and alkali, amount of the active mass of the electrode) exert an influence on the methanol oxidation rate. The catalyst on the basis of the Raney nickel promoted by 10 wt % Pt/Ru (1/9 at. %) exhibits maximum activity in the methanol electrooxidation reaction in a solution that contains 4 M CH3OH in 6 M KOH. Upon elevating temperature by 20°C in the temperature interval 40 to 80°C the reaction accelerates by 2–3 times. __________ Translated from Elektrokhimiya, Vol. 41, No. 12, 2005, pp. 1422–1430. Original Russian Text Copyright ? 2005 by Karichev, Tarasevich, Efremov, Bogdanovskaya, Kapustin.  相似文献   
10.
生物质衍生物糠醛还原胺化是合成糠胺的一种有效方法。本文以糠醛为原料、氨水为氨源,使用商业Raney Ni催化糠醛还原胺化合成糠胺,考察了氢压、温度、n(糠醛)/n(氨水)、溶剂、催化剂用量等条件对反应的影响。实验结果表明:在1,4-二氧六环溶剂中,0.03 g Raney Ni、n(糠醛)/n(氨水)=1/2、130 ℃、2.0 MPa H2条件下反应3 h,糠醛转化率100%,糠胺选择性96.3%。与传统方法相比,该工艺实现了非贵金属催化剂作用下高选择性反应,具有操作简单、低成本、收率高等优点。   相似文献   
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