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酶-过渡金属配合物催化的动态动力学拆分研究进展 总被引:4,自引:1,他引:4
动态动力学拆分是合成具有光学活性化合物最方便和最有效的方法之一. 酶和金属配合物的结合扩展了这个方法的使用范围, 该方法的主要特征是用酶催化拆分和金属催化原位外消旋化未反应的底物, 克服了经典动力学拆分最高产率只有50%的缺陷. 概述了近几年这方面的研究进展. 相似文献
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郭庆君 《高等学校化学学报》2019,40(10):2104
以反式-1,2-二苯基乙二胺为原料合成了一系列磷酰胺类配体, 考察了该类配体在催化1,2-加成/内酯化串联反应合成手性3-取代苯酞化合物过程中的催化活性. 在最优条件下, 即在配体7d摩尔分数为20%时, 可以获得高达90%的收率及大于80% e.e.值的3-取代苯酞化合物; 该配体合成简单, 虽然作为催化剂使用量较大但较易回收再利用. 对反应机理进行了推测, 认为反应过程中形成的环状过渡态有助于提高反应的对映选择性. 相似文献
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开发了一种由金和钯催化π-活化由炔醇合成呋喃衍生物的集成方法.该合成策略是最显著的特点适用于带环辛基的底物,其适用范围比之前报道的有很大扩展.在Sonogashira反应条件下,由相应底物可直接得到环辛基呋喃.Pd在这些反应中起到2个重要作用:底物发生偶联反应的关键催化剂;通过π-活化促进炔醇中间体成环反应.该方法在一步合成3-碘呋喃反应中作用很突出,使通过偶联法进一步官能团化成为可能.我们还将AuBr_3用于多米诺成环/C-H键活化反应和无环前体的成环反应.本文结果表明,在该类成环反应中金和钯催化剂相辅相成. 相似文献
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本文简要介绍了2005年至今有机合成领域的进展,第一部份有机合成方法学的一些新进展中突出介绍了金属参与的有机合成反应、自由基介导的合成反应、"一个反应瓶"内的多步反应以及不对称反应四个方面;第二部份复杂天然产物全合成则以10个分子的为例介绍这方面的进展。 相似文献
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Dr. Sukalyan Bhadra Prof. Dr. Hisashi Yamamoto 《Angewandte Chemie (International ed. in English)》2016,55(42):13043-13046
Direct asymmetric synthesis of N‐chiral amine oxides was accomplished (up to 91:9 e.r.) by means of a bimetallic titanium catalyst. A hydroxy group situated at the γ‐position of the N stereocenter enables the desired N‐oxidation through dynamic kinetic resolution of the trivalent amine substrates. The method was further extended to the kinetic resolution of racemic γ‐amino alcohols with a preexisting stereocenter, giving an important class of enantioenriched (up to 99.9:0.1 e.r.) building blocks that are otherwise difficult to synthesize. 相似文献
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Gaoyuan Ma Prof. Dr. Mukund P. Sibi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(33):11644-11657
Biaryl compounds with axial chirality are very common in synthetic chemistry, especially in catalysis. Axially chiral biaryls are important due to their biological activities and extensive applications in asymmetric catalysis. Thus the development of efficient enantioselective methods for their synthesis has attracted considerable attention. This Minireview discusses the progress made in catalytic kinetic resolution of biaryl compounds and chronicles significant advances made recently in catalytic kinetic resolution of biaryl scaffolds. 相似文献
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Nicola Di Iorio Simone Crotti Giorgio Bencivenni 《Chemical record (New York, N.Y.)》2019,19(10):2095-2104
The enantioselective synthesis of atropisomers is an emerging field, that in recent years reached fundamental results and put the bases for innovative applications. Organocatalysis is playing a central role in the realization of original synthesis for novel atropisomeric scaffolds.[1] In this short review, we would like to highlight the results obtained by our group and others in the field of axially enantioselective desymmetrization reactions using organocatalysis as main strategy. 相似文献
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Synergistic Kinetic Resolution and Asymmetric Propargyl Claisen Rearrangement for the Synthesis of Chiral Allenes 下载免费PDF全文
Yangbin Liu Prof. Dr. Xiaohua Liu Haipeng Hu Jing Guo Yong Xia Dr. Lili Lin Prof. Dr. Xiaoming Feng 《Angewandte Chemie (International ed. in English)》2016,55(12):4054-4058
The asymmetric propargyl Claisen rearrangement provides a convenient entry to chiral allene motifs. Herein, we describe the development of a kinetic resolution and asymmetric rearrangement of racemic propargyl vinyl ethers. This transformation afforded chiral allene products along with the enantiomerically enriched substrate in good yields with excellent diastereo‐ and enantioselectivity. The complete chirality transfer and facially selective rearrangement enabled the simultaneous construction of an axially chiral allenic unit and a quaternary carbon stereocenter. 相似文献
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Gaoyuan Ma Dr. Jun Deng Prof. Dr. Mukund P. Sibi 《Angewandte Chemie (International ed. in English)》2014,53(44):11818-11821
Can organocatalysts that incorporate fluxional groups provide enhanced selectivity in asymmetric transformations? To address this issue, we have designed chiral 4‐dimethylaminopyridine (DMAP) catalysts with fluxional chirality. These catalysts were found to be efficient in promoting the acylative kinetic resolution of secondary alcohols and axially chiral biaryl compounds with selectivity factors of up to 37 and 51, respectively. 相似文献
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A short, elegant, and high yielding synthesis of ravoconazole is presented. The key step of this synthesis is an enantioselective palladium-catalyzed chiral zinc-allene addition reaction. The starting materials are 2-chloro-1-(2,4-difluorophenyl)-ethanone and (R)-4-phenylbutyn-2-ol obtained from enzymatic resolution of its racemate. 相似文献