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本文介绍了手性铁催化体系在酮及亚胺的不对称还原、烯烃及硫醚的不对称氧化、不对称环加成、不对称环丙烷化以及不对称Friedel-Crafts烷基化等反应中的应用. 相似文献
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Jesus M. Rodilla Patricia P. Neves Sofia Pombal Vicente Rives Raquel Trujillano David Díez 《Natural product research》2016,30(7):834-840
The use of hydrotalcites for the synthesis of two chiral building blocks in a simple way is described as a new and green methodology. The synthesis of these compounds implies a regioselective Baeyer–Villiger reaction in a very selective way with ulterior opening and lactonisation. This methodology should be considered green for the use of hydrogen peroxide as the only oxidant and hydrotalcites as the catalyst, and because no residues are produced apart from water. The procedure is very adequate for using in gram scale, in order to increase the value of the obtained compounds. The conditions are excellent and can be applied for nonstable compounds, as they are very mild. The synthesised compounds are magnific starting materials for the synthesis of biologically active or natural compounds. The use of a cheap, commercial and chiral compound as carvone disposable in both enantiomeric forms adds an extra value to this methodology. 相似文献
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探讨R-3-奎宁醇的合成工艺。通过手性合成的方法,以3-奎宁酮盐酸盐为原料,经CBS催化剂催化还原得R-3-奎宁醇。收率可达到92%以上,ee值可达98%以上。该合成路线操作步骤简单、收率高,具有工业应用价值。 相似文献
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手性金属催化剂在不对称环丙烷化反应中的应用进展 总被引:1,自引:0,他引:1
手性金属催化剂在不对称环丙烷化反应中的应用一直是不对称合成领域的一个热点。对三十多年来的这一领域的手性金属催化剂的发展作了详细的归纳和评述。 相似文献
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Pengfei Yan Chunhong Nie Guangming Li Guangfeng Hou Wenbin Sun Jinsheng Gao 《应用有机金属化学》2006,20(5):338-343
Heterometallic [(THF)2Na]3[Ln(R‐Binolate)3(H2O)] [Ln = Sm ( 1 ) and Gd ( 2 )] has been synthesized by the reactions of either LnCl3 or LnBr3 with 3 equiv. Na(R‐HBinolate) and characterized by X‐ray crystallographic analysis. Structural analyses proposed that 1 and 2 are isomorphous complexes, crystallizing in the hexagonal space group P63 with C3 symmetry. The coordination geometry of the lanthanide ions in 1 and 2 can be best approximated as a mono‐capped triangle antiprism. When complexes 1 and 2 were employed as catalysts in the Meerwein–Ponndorf–Verley (MPV) reactions of acetophenone, the S‐phenylethanol was separated in 94 and 85% enantiomeric excess (e.e.) for 1 and 2 , respectively. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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介绍了双中心协同催化作用的概念以及A型和B型两类催化剂。综述了A型催化 剂在不对称硝基-类羟醛反应、迈克尔加成反应、亚胺和醛的氢膦酰化反应、曼尼 希反应、不对称醛酮羟醛反应以及环氧开环反应中的应用;同时简要介绍了B型催 化剂在不对称合成中的应用。 相似文献
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Gómez Arrayás R Adrio J Carretero JC 《Angewandte Chemie (International ed. in English)》2006,45(46):7674-7715
Despite the impressive progress achieved in asymmetric catalysis during the last decade, an increasing number of new catalysts, ligands, and applications are reported every year to satisfy the need to embrace a wider range of reactions and to improve the efficiency of existing processes. Because of their availability, unique stereochemical aspects, and wide variety of coordination modes and possibilities for the fine-tuning of the steric and electronic properties, ferrocene-based ligands constitute one of the most versatile ligand architectures in the current scenario of asymmetric catalysis. Over the last few years ferrocene catalysts have been successfully applied in an amazing variety of enantioselective processes. This Review documents these recent advances, with special emphasis on the most innovative asymmetric processes and the development of novel, efficient types of ferrocene ligands. 相似文献
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Trost BM Malhotra S Mino T Rajapaksa NS 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(25):7648-7657
The asymmetric acylation of meso-2-substituted-1,3-propanediols by using an amphoteric chiral dinuclear zinc catalyst is described. It is has been demonstrated that both 2-alkyl- and 2-aryl-1,3-propanediols can be desymmetrized in high yields and enantioselectivities by using the same family of ligands. Given that both antipodes of the chiral catalyst are available, both enantiomers of the desymmetrized product can be obtained from the same starting material. The synthetic utility of the desymmetrized products has been demonstrated by the synthesis of several chiral building blocks with high enantiomeric purities. 相似文献
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新型手性配体的设计合成是不对称催化研究的重要内容,其中手性胺膦配体因同时含有"软"的磷原子和"硬"的氮原子而具有丰富的配位化学性能和优秀的不对称诱导能力.本文总结了本研究组最近设计合成的手性环状胺膦配体的制备、表征及其在铁催化酮的不对称还原中的应用.手性1,2-环己二胺与双(2-甲酰基苯基)苯基膦通过[2+2]环缩合反应能够顺利获得手性22元环的亚胺膦配体21,该配体经Na BH4还原后生成大环胺膦配体22.利用手性大环胺膦配体22与Fe3(CO)12原位生成的催化体系,能够高活性、高对映选择性地实现包括杂环芳香酮在内50多种酮的不对称转移氢化和不对称氢化反应,其S/C(底物与催化剂的摩尔比)最高可达5000:1,产物手性芳香醇的光学纯度高达99%ee. 相似文献
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Naoyoshi Maezaki Suguru YagiShizuka Ohsawa Hirofumi OhishiTetsuaki Tanaka 《Tetrahedron》2003,59(50):9895-9906
Novel asymmetric sulfinylzincation of alkynoates has been accomplished via a Pd-catalyzed sulfinylzincation using 1-alkynyl sulfoxides bearing chiral auxiliaries as a sulfinylating reagent. The reaction proceeded in a highly syn-selective fashion, giving the (E)-β-sulfinyl α,β-unsaturated ester exclusively. Among the chiral sulfinylating reagents tested, an isoborneol-type compound (Rs)-4 showed the best results in terms of both yield and diastereoselectivity. As a result of optimization of the reaction, the selectivity was improved up to 92:8 dr, and stereochemistry of the newly formed sulfur stereogenic center was revealed as (Ss)-configuration. 相似文献
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Shinichi Itsuno Yosuke Hashimoto Naoki Haraguchi 《Journal of polymer science. Part A, Polymer chemistry》2014,52(21):3037-3044
This article details the enantioselective catalytic performance of crosslinked, polymer immobilized, Ir‐based, chiral complexes for transfer hydrogenation of cyclic imines to chiral amines. Polymerization of the achiral vinyl monomer, divinylbenzene, and a polymerizable chiral 1,2‐diamine monosulfonamide ligand followed by complexation with [IrCl2Cp*]2 affords the crosslinked polymeric chiral complex, which can be successfully applied to asymmetric transfer hydrogenation of cyclic imines. Polymeric catalysts prepared from amphiphilic achiral monomers have high catalytic activity in the reaction and can be used both in organic solvents and water to give chiral cyclic amines with a high level of enantioselectivity (up to 98% ee). The asymmetric reaction allows for reuse of the heterogeneous catalyst without any loss in activity or enantioselectivity over several runs. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3037–3044 相似文献
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Easily available D-(+)-camphor-derived chiral mercapto-alcohols 2 and 3 were employed for catalytic asymmetric borane reduction of aromatic ketones. Moderate enantioselectivities with e.e. 20.2-72.1% were obtained with 10 mol% catalyst. Opposite asymmetric induction was achieved when mercapto-alcohols 2 and 3 were used. 相似文献
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The asymmetric catalysis reaction is considered to be an important way by which chiral compounds are generated. Chiral 1,3,2-oxazaborolidine, as an effective asymmetric catalyst, is used widely in the enantioselective reduction of prochiral ketones, imines, and carbon-carbon double bonds[1—3]. Up to now, a number of quantum chemical modeling investigations of the en-antioselective reduction of prochiral ketones with borane catalyzed by chiral oxazaborolidines have been carried out[4—7]. Howe… 相似文献
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This article describes the generation of chiral palladium enolates and their application to several kinds of catalytic asymmetric reactions. Two methods to generate chiral enolates were developed using novel cationic palladium complexes 1 and 2 . In these processes, water or a hydroxo ligand on palladium metal plays an important role as a nucleophile to promote the transmetallation or as a Brønsted base to abstract an acidic α‐proton of the carbonyl group. These enolates showed sufficient reactivity with various electrophiles. Using a chiral Pd enolate as a key intermediate, highly enantioselective reactions such as catalytic aldol reactions, Mannich‐type reactions, Michael reactions, and fluorination reactions were developed. The unique structures of the palladium enolate complexes were elucidated and reaction mechanisms are proposed. © 2004 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 4: 231–242; 2004: Published online in Wiley InterScience ( www.interscience.wiley.com ) DOI 10.1002/tcr.20017 相似文献
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Ana Lúcia Cardoso Ana Matos Beja Jesús M. de los Santos Francisco Palacios 《Tetrahedron》2009,65(45):9116-7725
The synthesis of chiral functionalized β-amino esters via the hydride reductive amination of chiral allenes was explored. These compounds can be regarded as β-peptoids building blocks bearing a chiral side chain at the nitrogen and at the same time retaining the β-amino acid side chain. β-Enamino esters were obtained from the nucleophilic addition of α-amino esters (l-Ala, d-Ala, l-Phe, l-Leu, l-Trp and d-Trp methyl esters) to 2,3-allenoates bearing a chiral auxiliary, which determines the stereochemistry outcome of the subsequent reduction reaction. It was also demonstrated that in the reduction of β-enamino esters derived from l-Pro and d-Pro methyl esters the chirality of the new chiral center is controlled by the α-amino ester moiety. 相似文献
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Recent advances in asymmetric phase-transfer catalysis 总被引:1,自引:0,他引:1
The use of chiral nonracemic onium salts and crown ethers as effective phase-transfer catalysts have been studied intensively primarily for enantioselective carbon-carbon or carbon-heteroatom bond-forming reactions under mild biphasic conditions. An essential issue for optimal asymmetric catalysis is the rational design of catalysts for targeted reaction, which allows generation of a well-defined chiral ion pair that reacts with electrophiles in a highly efficient and stereoselective manner. This concept, together with the synthetic versatility of phase-transfer catalysis, provides a reliable and general strategy for the practical asymmetric synthesis of highly valuable organic compounds. 相似文献