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FENG Xiaoming 《高等学校化学研究》2001,17(3)
Chiral titanium complexes is very importance catalyst to asymmetric catalytic reactions. A series of catalytic systems based on titanium-chiral ligands complexes has been reported. This presentation will discuss some of our recent progress on asymmetric catalytic reactions catalyzed by chiral titanium complexes. 相似文献
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手性咪唑啉酮类有机催化剂催化的不对称反应 总被引:1,自引:0,他引:1
近年来,不对称有机催化过程日趋成熟,用于越来越多的实际应用。相对于金属催化过程有机胺催化剂具有许多潜在的优势:相对比较稳定,价格较低,容易得到,没有金属泄露到环境或产品中的风险以及对操作环境要求不高等,有机胺催化已被证明是实现不对称转化的有效手段。手性咪唑啉酮催化剂是有机胺催化剂中重要的一种类型。本文总结了手性咪唑啉酮催化剂在Diels-Alder反应、1,3-偶极环加成、Michael反应、Friedel-Crafts烷基化等不对称催化反应中的应用研究进展,并对未来手性咪唑啉酮在工业中的应用作了展望。 相似文献
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Chiral phosphines are versatile Lewis basic catalysts that are capable of promoting a wide range of asymmetric reactions. In particular, recently designed chiral phosphines based on the concept of bi‐/multifunctionality have been demonstrated to be effective catalysts for many types of asymmetric reactions, such as (aza)‐MBH reactions, cycloaddition reactions, and nucleophilic addition reactions. This short overview summarizes the recent advances in this field and highlights the most‐significant achievements. 相似文献
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不对称催化环氧化反应 总被引:5,自引:0,他引:5
本文综述了不对称催化环氧化体系的研究进展。重点评述了Sharpless-Kat-suki不对称环氧化反应的特点、机理、新进展与应用,综合分析了由手性(salen)Mn(Ⅲ)催化剂对非功能化烯烃所创建的突出成果与应用前景。 相似文献
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Chun‐Xiang Zhuo Prof. Dr. Wei Zhang Prof. Dr. Shu‐Li You 《Angewandte Chemie (International ed. in English)》2012,51(51):12662-12686
This Review summarizes the development of catalytic asymmetric dearomatization (CADA) reactions. The CADA reactions discussed herein include oxidative dearomatization reactions, dearomatization by Diels–Alder and related reactions, the alkylative dearomatization of electron‐rich arenes, transition‐metal‐catalyzed dearomatization reactions, cascade sequences involving asymmetric dearomatization as the key step, and nucleophilic dearomatization reactions of pyridinium derivatives. Asymmetric dearomatization reactions with chiral auxiliaries and catalytic asymmetric reactions of dearomatized substrates are also briefly introduced. This Review intends to provide a concept for catalytic asymmetric dearomatization. 相似文献
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We introduce here a strategy that enables effective addition of lithium enolates of acetates to aldimines. The new method depends strongly on the use of o-alkoxy (or o-fluoro) aniline-derived aldimines which have been found to have a potential effect on the enolate addition. This scope was expanded to the asymmetric process using the chiral acetate. A Lewis acid additive has a complementary role in the pronounced activation of imine functionalities. 相似文献
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手性高烯丙基醇类化合物是一类非常重要的有机合成中间体,被广泛应用于药物分子和天然产物的合成中,不对称羰基ene反应是构建此类化合物最有效的方法之一,近年来已经取得了巨大进展。目前,在不对称羰基ene反应中的手性催化剂主要有如Mg、Ca、Sc、Ti、Co、Ni、Cu、Rh、Pd、Pt等金属与手性配体络合形成的配合物,以及一些手性有机小分子,大部分都取得了较好的催化活性与对映选择性。本文就此评述了各类手性催化剂在不对称羰基ene反应中的应用,不对称诱导反应的机理,以及催化剂分子结构及反应条件对催化活性和对映选择性的影响。 相似文献
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LIYan-yun CHENJian-shan YANGChuan-bo DONGZhen-rong LIBao-zhu ZHANGHui GAOJing-xing TAKAOIkariya 《高等学校化学研究》2004,20(2):180-184
The efficient chiral Ru3(CO)12 systems were prepared in situ from Ru3(CO)12 and various chiral diiminoor diamino-diphosphine tetradentate ligands. The systems have been used for the asymmetric transfer hydrogenation of propiophenone in 2-propanol, leading to 1-phenyl-1-propanol in a 98% yield and 96% e.e. The IR study suggests that the carbonyl hydride anion [HRu3(CO)11]^- most probably exists as a principal species under the reaction conditions. The high chiral efficiency may be due to the synergetic effect produced by the neighboring ruthenium atoms and a special chiral micro-environment involving the polydentate ligand and the Ru3 framework. 相似文献
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本文综述了近年来在无溶剂条件下进行的一些不对称催化反应的进展, 着重介绍了无溶剂条件下的不对称Aldol反应、环氧化合物不对称开环反应、外消旋环氧化合物的拆分、不对称Diels-Alder反应、金属有机试剂对醛酮的不对称加成反应、不对称氢化反应、不对称氢甲酰化反应、不对称烯烃复分解反应、不对称Michael加成反应、不对称氧化反应、不对称Friedel-Crafts反应等, 同时展望了无溶剂不对称催化反应的研究前景。 相似文献
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