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手性叔醇结构广泛存在于生物活性物质、天然产物和药物分子中,实现其高效不对称催化合成具有重要意义.消旋醇的动力学拆分是一种合成高光学纯度手性醇的重要方法,然而由于叔醇α-碳上带三个不同的非氢取代基团,手性识别难度较大,因而发展高效且具有广泛底物适用性的叔醇动力学拆分方法具有较大的挑战.尽管如此,近年来非酶催化的叔醇的动力学拆分领域取得了快速的发展,一些新颖的不对称催化反应、催化体系被成功应用于叔醇的动力学拆分反应中.对叔醇动力学拆分反应进行了系统总结,分类介绍了这些反应的底物适用性、特点、机理以及局限等,并对该领域的未来发展进行展望. 相似文献
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《有机化学》2015,(3):742
<正>J.Am.Chem.Soc.2014,136,17426~17429链状手性脂肪醇结构广泛存在于天然产物分子中,也是许多手性药物的重要结构组成部分.尽管化学家们在过去几十年中已经发展了许多不对称合成方法,但手性脂肪醇的高效、高选择性合成仍然是一个挑战.例如,羰基化合物的不对称催化氢化反应目前仅适用于具有大位阻烷基的手性脂肪醇的合成.因此,从消旋的手性脂肪醇进行动力学拆分仍然是获取光学活性手性脂肪醇的主要方法.然而,在目前已报道的消旋手性脂肪醇的动力学拆分中,一个对映异构体的羟基被转变成其它官能团,因而损失了一半的底物.最近,南开大学元素有机化学研究所周其林、谢建 相似文献
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论述了动态动力学拆分的原理,介绍了化学酶法拆分消旋体胺类化合物的反应和近年来的研究进展;指出手性胺是构成许多中间体的基础化合物,化学酶法动态动力学拆分是制备单一手性胺类化合物的重要方法. 相似文献
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最近,酶催化不对称还原反应和消旋动力学拆分,在合成光学活性物质的方法上,有较大进展,有些反应已有实用价值。酶催化反应中,所用的酶往往直接利用生物体本身,来源方便,价格低廉,操作简便。目前,在酶催化反应中,以羰基的不对称还原应用最广。与此有关的酶催化消旋动力学拆分的研究也日益增多。本文对这两方面的最新研究情况作一简要介绍。 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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Lisa K. Thalén Dongbo Zhao Dr. Jean‐Baptiste Sortais Dr. Jens Paetzold Dr. Christine Hoben Dr. Jan‐E. Bäckvall Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(14):3403-3410
Dynamic transformation : A racemization catalyst and the enzyme Candida antarctica lipase B (CALB) were combined in a one‐pot dynamic kinetic resolution (DKR) of primary amines, which were transformed to their corresponding amides in up to 95 % yield and >99 % ee. This chemoenzymatic DKR was also applied to the synthesis of norsertraline (see scheme).
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Dr. Jingyun Ren Dr. Xu Ban Dr. Xin Zhang Dr. Siu Min Tan Dr. Richmond Lee Prof. Dr. Choon-Hong Tan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(23):9140-9143
We have developed a method to afford enantiomerically enriched tertiary azides and bromides through pentanidium-catalyzed kinetic resolution (KR) of racemic tertiary bromides under base-free conditions. We found that the absence of water is crucial to attain a high selectivity factor (s). On the other hand, new experimental observations and DFT modeling led us to propose that enantioconvergent azidation of tertiary bromides proceeded through dynamic kinetic resolution (DKR). The investigations particularly identified the crucial roles of base and water in the enantioconvergent process, thus supporting the proposal that the tertiary bromide isomerizes in the presence of base and water through a SN2X pathway. 相似文献
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Stereochemically Rich Polycyclic Amines from the Kinetic Resolution of Indolines through Intramolecular Povarov Reactions 下载免费PDF全文
Chang Min Prof. Dr. Daniel Seidel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(31):10817-10820
Under control of a chiral Brønsted acid catalyst, racemic indolines undergo intramolecular Povarov reactions with achiral aromatic aldehydes bearing a pendent dienophile. One enantiomer of the indoline reacts preferentially, resulting in the highly enantio‐ and diastereoselective formation of polycyclic heterocycles with four stereogenic centers. This kinetic resolution approach exploits the differential formation/reactivity of diastereomeric ion pairs. 相似文献
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Lu Ran Yu Chen Yanqiu Zhu Huanyu Cai Huaji Pang Dingce Yan Prof. Yonggang Xiang Prof. Huailong Teng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(16):e202319732
Bio-catalysis represents a highly efficient and stereoselective method for the synthesis of valuable chiral compounds, however, the poor stability and limited reaction types of free enzymes restrict their wide application in industrial production. In this work, to overcome these problems, a multifunctional photoenzymatic nanoreactor CALB@COF-Ir was developed through the encapsulation of Candida antarctica lipase B (CALB) in a photosensitive covalent organic framework COF-Ir . This bio-nanocluster serves as efficient catalysts in asymmetric dynamic kinetic resolution (DKR) of secondary amines to give a series of chiral amines in high yields (up to 99 %) and enantioselectivities (up to 99 % ee). The well-designed COF-Ir not only acts as safety cover to prevent CALB from deactivation but promotes racemization of secondary amines via photo-induced hydrogen atom transfer (HAT) process. Photoelectric characterization and TDDFT calculation revealed that (ppy)2Ir units in COF-Ir play crucial role in this photocatalytic system which enhance its photo-redox properties through facilitating the separation between photoelectrons (e−) and holes (h+). Furthermore, the heterogeneous photoenzymatic nanoreactor could be recycled for five rounds with slight decline of catalytic reactivity. 相似文献
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Chiral Phosphoric Acid Catalyzed Asymmetric Ugi Reaction by Dynamic Kinetic Resolution of the Primary Multicomponent Adduct 下载免费PDF全文
Yun Zhang Dr. Yu‐Fei Ao Prof. Dr. Zhi‐Tang Huang Prof. Dr. De‐Xian Wang Prof. Dr. Mei‐Xiang Wang Prof. Dr. Jieping Zhu 《Angewandte Chemie (International ed. in English)》2016,55(17):5282-5285
Reaction of isonitriles with 3‐(arylamino)isobenzofuran‐1(3H)‐ones in the presence of a catalytic amount of an octahydro (R)‐binol‐derived chiral phosphoric acid afforded 3‐oxo‐2‐arylisoindoline‐1‐carboxamides in high yields with good to high enantioselectivities. An enantioselective Ugi four‐center three‐component reaction of 2‐formylbenzoic acids, anilines, and isonitriles was subsequently developed for the synthesis of the same heterocycle. Mechanistic studies indicate that the enantioselectivity results from the dynamic kinetic resolution of the primary Ugi adduct, rather than from the C?C bond‐forming process. The resulting heterocycle products are of significant medicinal importance. 相似文献
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Jingyun Ren Xu Ban Xin Zhang Siu Min Tan Richmond Lee Choon‐Hong Tan 《Angewandte Chemie (International ed. in English)》2020,59(23):9055-9058
We have developed a method to afford enantiomerically enriched tertiary azides and bromides through pentanidium‐catalyzed kinetic resolution (KR) of racemic tertiary bromides under base‐free conditions. We found that the absence of water is crucial to attain a high selectivity factor (s). On the other hand, new experimental observations and DFT modeling led us to propose that enantioconvergent azidation of tertiary bromides proceeded through dynamic kinetic resolution (DKR). The investigations particularly identified the crucial roles of base and water in the enantioconvergent process, thus supporting the proposal that the tertiary bromide isomerizes in the presence of base and water through a SN2X pathway. 相似文献
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Dr. Anthony Choi Dr. Ashraf El-Tunsi Yuhang Wang Prof. Anthony J. H. M. Meijer Jia Li Dr. Xiabing Li Dr. Ilaria Proietti Silvestri Prof. Iain Coldham 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(45):11670-11675
Kinetic resolution of 2-arylindolines (2,3-dihydroindoles) was achieved by treatment of their N-tert-butoxycarbonyl (Boc) derivatives with n-butyllithium and sparteine in toluene at −78 °C followed by electrophilic quench. The unreacted starting materials together with the 2,2-disubstituted products could be isolated with high enantiomer ratios. Variable temperature NMR spectroscopy showed that the rate of Boc rotation was fast (ΔG≠≈57 kJ/mol at 195 K). This was corroborated by DFT studies and by in situ ReactIR spectroscopy. The enantioenriched N-Boc-2-arylindolines were converted to 2,2-disubstituted products without significant loss in enantiopurity. Hence, either enantiomer of the 2,2-disubstituted products could be obtained with high selectivity from the same enantiomer of the chiral ligand sparteine (one from the kinetic resolution and the other from subsequent lithiation-trapping of the recovered starting material). Secondary amine products were prepared by removing the Boc group with acid to provide a way to access highly enantioenriched 2-aryl and 2,2-disubstituted indolines. 相似文献