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In the last decade, planar chiral ferrocenes have attracted a growing interest in several fields, particularly in asymmetric catalysis, medicinal chemistry, chiroptical spectroscopy and electrochemistry. In this frame, the access to pure or enriched enantiomers of planar chiral ferrocenes has become essential, relying on the availability of efficient asymmetric synthesis procedures and enantioseparation methods. Despite this, in enantioseparation science, these metallocenes were not comprehensively explored, and very few systematic analytical studies were reported in this field so far. On the other hand, enantioselective high-performance liquid chromatography has been frequently used by organic and organometallic chemists in order to measure the enantiomeric purity of planar chiral ferrocenes prepared by asymmetric synthesis. On these bases, this review aims to provide the reader with a comprehensive overview on the enantioseparation of planar chiral ferrocenes by discussing liquid-phase enantioseparation methods developed over time, integrating this main topic with the most relevant aspects of ferrocene chemistry. Thus, the main structural features of ferrocenes and the methods to model this class of metallocenes will be briefly summarized. In addition, planar chiral ferrocenes of applicative interest as well as the limits of asymmetric synthesis for the preparation of some classes of planar chiral ferrocenes will also be discussed with the aim to orient analytical scientists towards ‘hot topics’ and issues which are still open for accessing enantiomers of ferrocenes featured by planar chirality. 相似文献
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Ma JA 《Chemical Society reviews》2006,35(7):630-636
Catalytic asymmetric reactions provide one of the most powerful and economical synthetic approaches to a variety of enantiomerically enriched compounds. As being analogues of the corresponding alpha- and beta-amino acids, optically active alpha- and beta-amino phosphonic acid derivatives have found widespread use in medicinal chemistry and the pharmaceutical sciences. Using catalytic amounts of chiral materials, asymmetric synthesis of enantiomerically enriched alpha- and beta-amino phosphonates has been a subject of growing interest. This tutorial review contains a compilation of the catalytic asymmetric synthetic methods developed to date and highlights their utility for obtaining these target compounds. 相似文献
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In the age of high-throughput biology, novel genes and proteins are emerging quickly. The need for developing organic synthesis-derived methods that allow rapid access to polyfunctional, complex natural product-like compounds is growing constantly, largely because these small-molecule-based compounds serve as smart, powerful tools both in understanding the roles and functions of emerging biological targets and in validating their biological responses. Developing asymmetric synthesis-derived organic reactions on solid phase allows the synthesis of complex natural product-like compounds in a high-throughput manner. Solid phase organic synthesis is now commonly utilized in the library synthesis of rather simple compounds (i.e., compounds with no multiple stereogenic centers). With few exceptions, the synthesis of complex natural product-like derivatives is still in its infancy. Some recent efforts made in this area indicate opportunities yet to be explored. 相似文献
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(R)-α-硫辛酸可用于预防和治疗糖尿病及相关并发症,也可以作为保健品使用,用途广泛,因而其高效合成方法长期以来受到广泛关注。 目前,合成(R)-α-硫辛酸的方法主要有酶和化学方法催化的不对称合成、消旋体的手性拆分以及手性底物控制的不对称合成。 本文将以此为分类标准,对目前所报道的(R)-α-硫辛酸合成方法进行总结归纳和展望。 相似文献
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Dr. Sreekumar Vellalath Prof. Dr. Daniel Romo 《Angewandte Chemie (International ed. in English)》2016,55(45):13934-13943
Although acylammonium salts are well‐studied, chiral α,β‐unsaturated acylammonium salts have received much less attention. While these intermediates are convenient synthons, which are readily available from several commodity unsaturated acids and acid chlorides, and possess three reactive sites, their application in organic synthesis has been limited because of the lack of appropriate chiral Lewis bases for their generation. In recent years, the utility of chiral, unsaturated acylammonium salts has expanded considerably, thus demonstrating the unique reactivity of this intermediate leading to the development of a diverse array of catalytic, asymmetric transformations including organocascade processes. This Minireview highlights the recent and growing interest in these intermediates which might spark further research into their untapped potential for asymmetric organocascade catalysis. A cursory comparison is made to related unsaturated iminium and acylazolium intermediates. 相似文献
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Giovanni Centonze Chiara Portolani Prof. Paolo Righi Prof. Giorgio Bencivenni 《Angewandte Chemie (International ed. in English)》2023,62(31):e202303966
Axially chiral compounds have been always considered a laboratory curiosity with rare prospects of being applied in asymmetric synthesis. Things have changed very quickly in the last twenty years when it was understood the important role and the enormous impact that these compounds have in medicinal, biological and material chemistry. The asymmetric synthesis of atropisomers became a rapidly expanding field and recent reports on the development of N−N atropisomers strongly prove how this research field is a hot topic open to new challenges and frontiers of asymmetric synthesis. This review focuses on the recent advances in the enantioselective synthesis of N−N atropisomers highlighting the strategies and breakthroughs to obtain this novel and stimulating atropisomeric framework. 相似文献
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Michael D. Gróning Bradley J. Rowe Christopher D. Spilling 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract Chiral α-hydroxyphosphonates are biologically active2 and are flexible precursors for other α and γ substituted phosphonates 3 The fact that the biological activity is oRen dependent on the absolute configuration of the a-position has resulted in a growing interest in methods for the asymmetric synthesis of hydroxyphosphonates 1Potentially, the most efficient and economic route to these compounds involves enantioselective catalvsis. 相似文献
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A new enzymatic method for the preparation of optically active alpha-substituted carboxylic acids is reported. This technique is called deracemization reaction, which provides us with a route to obtain the enantiomerically pure compounds, theoretically in 100% yield starting from the racemic mixture. This means that the synthesis of a racemate is almost equal to the synthesis of the optically active compound, and this concept is entirely different from the commonly accepted one in the asymmetric synthesis. Using the growing cell system of Nocardia diaphanozonaria JCM3208, racemates of 2-aryl- and 2-aryloxypropanoic acid are deracemized smoothly and (R)-form-enriched products are recovered in high chemical yield (>50%). In addition, using optically active starting compounds and deuterated derivatives as well as inhibitors, we have disclosed the fact that a new type of enzyme takes part in this biotransformation, and that the reaction proceeds probably via the same mechanism as that in rat liver. 相似文献
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近年来,用聚合物负载的手性催化剂和手性试剂完成的不对称合成反应主要集中在潜手性酮的不对称还原反应;烯烃的不对称双羟基化反应;烯烃的不对称环氧化反应;不对称Diels-Alder反应和饱和碳原子上的不对称取代反应。就近十年来聚合物负载手性催化剂和手性试剂的合成及应用进行了讨论。 相似文献
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有机锡在不对称合成中的应用研究进展 总被引:7,自引:0,他引:7
金属有机化合物是不对称合成中常用的有机试剂。有机锡试剂易于制备,而且碳-锡键又易于断开,因此它们被广泛应用于有机合成中,当然也是不对称合成常用的试剂之一,是制备某些手性天然产物必备的试剂。由于锡的结构特点,它可以形成四配位、五配位甚至六配位的配合物,这些配合物作为路易斯酸可用作不对称合成中的催化剂、助催化剂。从已报道的文献看,大多数反应的产率及对映体选择性都在中等或中等以上水平,某些已达到了优良的水平。本文综述了有机锡作为反应试剂、催化剂、助催化剂在不对称合成中的应用。 相似文献
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Patricia Rodríguez-Salamanca Prof. Rosario Fernández Dr. Valentín Hornillos Prof. José M. Lassaletta 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(28):e202104442
Molecules with restricted rotation around a single bond or atropisomers are found in a wide number of natural products and bioactive molecules as well as in chiral ligands for asymmetric catalysis and smart materials. Although most of these compounds are biaryls and heterobiaryls displaying a C−C stereogenic axis, there is a growing interest in less common and more challenging axially chiral C−N atropisomers. This review offers an overview of the various methodologies available for their asymmetric synthesis. A brief introduction is initially given to contextualize these axially chiral skeletons, including a historical background and examples of natural products containing axially chiral C−N axes. The preparation of different families of C−N based atropisomers is then presented from anilides to chiral five- and six-membered ring heterocycles. Special emphasis has been given to modern catalytic asymmetric strategies over the past decade for the synthesis of these chiral scaffolds. Applications of these methods to the preparation of natural products and biologically active molecules will be highlighted along the text. 相似文献
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4-(2'-Naphthoxy)-2-butenolide, readily available with high enantiopurity by a dynamic kinetic asymmetric transformation (DYKAT) of racemic 4-acyloxybutenolides (available in two steps from furfural), serves as an excellent chiral building block where the naphthoxy group strongly directs the stereochemistry of cycloadditions to the double bond. Notably, the cycloadditions of trimethylenemethanepalladium intermediates which do not exhibit good diastereoselectivity in additions to acceptors that possess many common and important chiral auxiliaries undergo cycloadditions with excellent regio- and stereocontrol. The utility of this process set the stage for an efficient new synthesis of (+)-brefeldin A, a compound of growing pharmacological significance. This synthesis also highlights the Pd-catalyzed DYKAT of crotyl carbonate to create the remote stereocenter. A new two-step method to convert aldehydes to delta-hydroxy-E-alpha,beta-enoates is also outlined. 相似文献
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糖类化合物价廉易得,具有天然手性结构,糖环上的多个羟基经过修饰,可以连接多种官能团。近年来手性糖类化合物的合成与应用研究引起了人们的广泛关注,尤其是在不对称合成和催化中的应用研究已成为有机化学中非常活跃的领域。碳水化合物含磷手性配体在不对称催化反应中的应用研究进展十分迅速,本文综述了近年来碳水化合物含磷手性配体与金属形成络合物作为催化剂,在不对称催化氢化、不对称烯丙位取代和不对称氢甲酰化等反应中的研究进展。 相似文献