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温控相转移催化——水/有机两相催化新进展 总被引:14,自引:0,他引:14
综述了“温控相转移催化”的原理,温控膦配体的设计、合成及其在水溶性极小的底物高碳烯烃的水/有机两相氢甲酰化反应中的应用效果. 相似文献
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Nonionic water soluble complex Ru 3(CO) 9(PETPP) 3 with the function of thermoregulated phase transfer catalysis was prepared. The catalytic activity and the recycle effect of Ru 3(CO) 9(PETPP) 3 for hydrogenation of styrene in aqueous/organic biphase catalysis system were studied. In addition, effects of reaction temperature, hydrogen pressure and reaction time were also investigated. The results showed that the reaction takes place mainly in organic phase at higher temperature (80 ℃). Under the conditions of θ =80 ℃, p (H 2)=2 MPa and t =3 h, both the PhCH∶CH 2 conversion and PhC 2H 5 selectivity are 100%. The PhCH∶CH 2 conversion is still 98 2% after reuse of the catalyst for 20 times. The catalytic performance of Ru 3(CO) 9(TPPTS) 3, Ru 3(CO) 9(PETPP) 3, Ru 3(CO) 9(TPPMS) 3 and Ru 3(CO) 9(TPP) 3 for biphase hydrogenation of styrene was compared. The experimental results for Ru 3(CO) 9(PETPP) 3 verified that there is a thermoregulated phase transfer catalysis process in the reaction system. 相似文献
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首次将具有"温控相转移催化"功能的非离子表面活性水溶性膦/铑配合物用于以CO为还原剂的水/有机两相芳香硝基物选择还原反应.以邻氯硝基苯为底物考察了反应温度、CO压力、底物浓度、催化剂浓度和水/有机两相体积比等对反应转化率和选择性的影响.结果表明,当反应条件为150℃和4MPa,反应32h时,邻氯硝基苯的转化率为98%,邻氯苯胺的选择性接近100%.动力学研究表明,底物浓度和催化剂浓度分别对反应速率呈一级,反应的表观活化能Ea=131.13kJ/mol. 相似文献
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将具有“高温混溶、室温分相”特征的温控PEG(聚乙二醇)两相催化体系用于三聚丙烯氢甲酰化反应.系统研究了以Rh(acac)(CO)2/TMPGP(TMPGP:P[O(CH2CH2O)nCH3]3,n=8)为催化剂时各种反应条件对三聚丙烯氢甲酰化反应的影响,并考察了催化剂的循环使用效果.在合成气压力6MPa(CO/H2体积比为1)及温度为130℃的反应条件下,三聚丙烯氢甲酰化反应的转化率和醛收率可分别达77%和75%.室温下分离得到的含催化剂的PEG相循环使用11次,催化剂活性基本保持不变,第一次循环的铑流失率为1.5%(质量分数),11次循环的平均铑流失率为0.69%.于-20℃下分相得到的催化剂相可循环使用15次,其催化活性保持不变,第一次循环的铑流失率可降至0.16%. 相似文献
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本文以作者在温控水/有机两相及温控非水液/液两相催化领域的研究工作为主线,对这一领域的研究进展作一评述,重点是环绕经典水/有机两相催化体系存在“应用范围受底物水溶性限制”的根本问题展开。特别是对“温控相转移催化”作了较为详细的介绍,同时,按体系介质不同,对氟两相体系、PEG两相体系、离子液体两相体系等非水液/液两相体系以及温控相分离催化分别作了阐述。 相似文献
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温控非水液/液两相催化,是指一类由两种或多种液态有机物组成的催化反应体系,其特点是体系的相态变化可通过温度来调控,即体系在高温时相互混溶呈均相,低温不溶分成两相,催化剂和产物分别处于两相,从而为解决均相催化剂分离难的问题开拓了一个新方向,是液/液两相催化研究领域最引人注目的进展之一.首次以"温控"为主线将氟两相催化作为温控液/液两相催化的一个特定类型纳入"温控非水液/液两相催化"范畴,并与其它通过温度来调控的有机液/液两相和作者提出的温控相分离催化串在一起作一较为详细的评述. 相似文献
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A brief overview of our recent research results of thermoregulated liquid/liquid biphasic catalysis is presented. Emphasis is given to the general principles of thermoregulated phase-transfer catalysis (TRPTC) and thermoregulated phase-separable catalysis (TPSC). In addition, the applications of TRPTC and TPSC in biphasic catalysis are also discussed. The introduction of TRPTC to biphasic system is free from the shortcomings of classical aqueous/organic two-phase catalysis, in which the application scope is restrained by the water solubility of the substrate. Meanwhile, TPSC provides a very simple and reliable way to deal with the separation of catalyst in homogeneous catalysis. The common advantages of TRPTC and TPSC are characterized by homogeneous catalysis coupled with convenient biphasic separation. 相似文献
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Ya Dong LU Yan Hua WANG Zi Lin JIN 《中国化学快报》2006,17(2):255-257
Liquid/liquid biphasic catalysis is a great success, which was successfully used in severallarge-scale industrial applications1-3. However, in liquid/liquid biphasic catalysis thecatalyst is usually immobilized in one of the two phases. A basic problem is… 相似文献
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温控配体与液/液两相催化 总被引:2,自引:2,他引:2
以作者近年的研究工作为主,对液/液两相催化研究领域取得的进展做一综述.着重介绍了以温控配体为基础的新型液/液两相催化过程温控相转移催化(thermoregulatedphasetransfercatalysis,TRPTC)和温控相分离催化(thermoregulatedphase-separablecatalysis,TPSC)的基本原理及其在高碳烯烃氢甲酰化、芳香硝基化合物的CO选择性还原及烯烃加氢等反应中的应用.基于温控配体在水中的“浊点”特性而提出的温控相转移催化概念,为从根本上解决水/有机两相催化
的适用范围受底物水溶性限制的问题提供了一条新途径.而利用温控配体在某些有机溶剂中存在临界溶解温度(CST)的特性而实现的温控相分离催化,则使在高于临界溶解温度的反应温度时为均相的反应体系,在低温(<CST)时则分成两相,催化剂自成一相,形成一种具有“均相反应、两相分离”特色的液/液两相催化新体系. 相似文献
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The aqueous/organic biphasic hydroformylation of 1‐octene catalyzed by Co2(CO)8/Ph2P(CH2CH2O)nMe, an in situ formed thermoregulated phase‐transfer cobalt catalyst, has been developed. The catalyst activity in this biphasic system was as high as that in the homogeneous system. The yield of oxo‐products was 93% when the reaction was carried out at 180 °C and under 4.0 MPa syngas pressure for 20 h. The catalyst could be easily recovered in the aqueous phase by decanting after the reaction system was cooled, and reused in consecutive reaction without any treatment. The loss of Co in the organic phase was less than 1% on average of five successive runs. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献