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Xiu-Shuai Chen 《合成通讯》2016,46(11):917-941
Chiral phosphine-phosphoramidite ligands, featuring ready availability, easy modification, and stability towards air and moisture, have recently emerged as a new kind of robust ligands for asymmetric catalysis. They have been found to display wide utilities in various catalytic asymmetric reactions, giving excellent enantioselectivities in the Rh-, Ru-, and Ir-catalyzed asymmetric hydrogenation of C?C, C?O, and C?N double bonds; Rh-catalyzed asymmetric hydroformylation; Pd-catalyzed asymmetric hydrophosphorylation; Pd-catalyzed asymmetric allylic alkylation; Ag-catalyzed asymmetric [3 + 2] cycloaddition; and Cu-catalyzed conjugate addition and reduction. In this review, the progress on the development of chiral phosphine-phosphoramidite ligands in asymmetric catalysis has been summarized. 相似文献
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Chiral organobases are efficient catalysts used in asymmetric reactions. This review provided a summary of chiral organobases in the aspects of their properties and applications. 相似文献
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Cai F Pu X Qi X Lynch V Radha A Ready JM 《Journal of the American Chemical Society》2011,133(45):18066-18069
We demonstrate that allenes, chiral 1,2-dienes, appended with basic functionality can serve as ligands for transition metals. We describe an allene-containing bisphosphine that, when coordinated to Rh(I), promotes the asymmetric addition of arylboronic acids to α-keto esters with high enantioselectivity. Solution and solid-state structural analysis reveals that one olefin of the allene can coordinate to transition metals, generating bi- and tridentate ligands. 相似文献
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Asymmetric catalysis has always been the focus of attention for synthetic chemistry. In this review, we summarize recent advances in the synthesis and asymmetric catalysis application of chiral metal clusters, nanoclusters and nanoparticles. 相似文献
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<正>Asymmetric organocatalysis has been a robust tool for manufacturing optically active molecules, in addition to asymmetric metal and biocatalysis [1]. The development of new concepts and catalysts to enable the creation of efficient synthetic methods has been a longstanding activity in this field. During the last decades, a diverse spectrum of chiral organocatalysts, including ketones, amine, Br?nsted acids 相似文献
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Zijp EJ van der Vlugt JI Tooke DM Spek AL Vogt D 《Dalton transactions (Cambridge, England : 2003)》2005,(3):512-517
Chiral aminophosphines Ph2PN(R)(CH2)nN(R)PPh2 1-4 [n= 2, R = CH(CH3)(Ph) 1; n= 3, R = CH(CH2CH3)(Ph) 2, n= 2, R = CH(CH3)(1-naphthyl) 3; n= 2, R = CH(CH3)(C6H11) 4] were synthesized by the reaction of ClPPh2 with the appropriate easily accessible enantiopure amine building blocks. For compounds 1 and 2, the corresponding selenides 5 and 6 were prepared to determine the electronic character of the phosphine moieties. By reaction of 1 with either PdCl2(cod) or PdCl(CH3)(cod) the cis-complexes 7 and 8 were obtained. The molecular structure for complex 7, cis-[PdCl2(1)], was determined by X-ray crystallography. Reaction of PtCl2(cod) with 1 or 2 yielded the corresponding monomeric cis-isomers 9 and 10. The rhodium derivative [RhCl(CO)(1)] (11) was obtained as a mixture of cis and trans-isomers. Preliminary results in the rhodium catalyzed hydroformylation of styrene and vinyl acetate, with ee's up to 51% and high regioselectivities, showed the potential of these chiral aminophosphines for homogeneous catalysis. 相似文献
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Twelve new imidazole-based potential bi- and tridentate ligands were synthesized and characterized. Whereas in the first series the alpha-amino acid and imidazole moieties were linked by an amino bond, in the second series the tridentate ligands, containing two imidazole groups, were separated by an amide bond. The first series was obtained by the reductive amination of 2-phenylimidazole-4-carboxaldehyde with alpha-amino acid esters. The tridentate ligands were prepared from 2-phenylimidazole-4-carboxylic acid and chiral amines. In the Henry reaction, the amines were revealed as a more reactive species than the less nucleophilic amides, however the enantiomeric excesses were generally poor. 相似文献
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《Tetrahedron: Asymmetry》2003,14(8):951-961
Syntheses and applications of chiral N-heterocyclic carbenes are reviewed. The common features of successful enantioselective catalysts are identified, and the outlook for further investigations is discussed. 相似文献
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Defieber C Grützmacher H Carreira EM 《Angewandte Chemie (International ed. in English)》2008,47(24):4482-4502
Metal-catalyzed asymmetric processes offer one of the most straightforward ways to introduce stereogenic centers. Hence, the development of novel chiral ligands that can effectively induce asymmetry in reactions is crucial in modern organic synthesis. While many established chiral ligands bind to a metal through heteroatoms, structures that coordinate to metals through carbon atoms have received little attention so far. Here, we highlight the increasing number of such chiral chelating olefin ligands as well as their application in a variety of metal-catalyzed transformations. 相似文献
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合成对映体纯的药品、农用化学品及风味调料,对化学家来说是个巨大的挑战.目前采用多种不同的方法可以合成这些光学纯化合物,从工业化生产的角度来看,不对称催化反应作为获得光学纯化合物的一种手段,在众多方法中最具经济效益,同时也最具挑战性.该领域的大量出版物, 相似文献
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In recent years, N-heterocyclic carbenes (NHC) have proved to be a versatile class of spectator ligands in homogeneous catalysis. Being robust anchoring functions for late transition metals, their ligand donor capacity and their molecular shape is readily modified by variation of the substituents at the N-atoms and the structure of the cyclic backbone. After the first attempts to use chiral NHC ligands in asymmetric catalysis in the late 1990's, which initially met with limited success, several novel structural concepts have emerged during the past two years which have led literally to an explosion of the field. With a significant number of highly selective chiral catalysts based on chiral NHCs having been reported very recently, several general trends in the design of new NHC-containing molecular catalysts for stereoselective transformations in organic synthesis emerge. 相似文献
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Chelating chiral diphosphines are often used as ligands of organometallic complexes. However monophosphines, or more generally ligands with one phosphorus linked to one or several heteroatom, may also be useful. This review gives the main results obtained in that area, by considering the classes of monodentate chiral ligands bearing one P(III) atom and involved in asymmetric catalysis with organometallic complexes. 相似文献
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Covalent organic frameworks (COFs), covalently assembled from the condensation reactions of organic building blocks, are a fascinating class of functional porous materials with two- or three-dimensional crystalline organic structures. Generally, it is preferable to use symmetric and rigid building blocks to construct highly crystalline COFs with desired topology. On the other hand, the incorporation of chiral functional moieties in the building blocks would open up new applications such as asymmetric catalysis and chiral separation. This mini review highlights the principle strategies in the design and synthesis of chiral COFs. The interesting and potential applications of these chiral COFs for asymmetric catalysis and chiral separation are also summarized. This mini review aims to provide an up-to-date advancement of chiral COFs for asymmetric catalysis and chiral separation. 相似文献
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获得对映异构体纯的手性化合物在药物、农用化学品、香料等领域愈来愈引起了科学界和工业界的广泛关注.不对称催化反应作为获得光学纯化合物的一种有效手段,由于其手性增殖的突出优势而特别引人注目.不对称催化一般通过含有手性配体 相似文献
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《Tetrahedron: Asymmetry》2006,17(13):1944-1951
A series of macroporous copolymer beads were synthesized by THE free radical suspension copolymerization of (S)-glycidylmethacrylate (GMA), (S)-thiiranylmethylmethacrylate (TMA), or (R,R)-phenylglycidylmethacrylate (Ph-GMA) with ethyleneglycol dimethacrylate (EDMA) or divinylbenzene (DVB). This allowed for the evaluation of their chemical and physical properties (polymer matrix nature or the structure of the heterocyclopropane) and their influence on the catalytic efficiency. These chiral polymers were subsequently transformed into polyamino alcohol or polyamino thiol derivatives by the facile ring opening of the oxirane or thiirane group with benzylamine and methylamine. Complexed with [RuCl2(p-cymene)]2, these derivatives were shown to be effective in the asymmetric hydrogen transfer reduction of acetophenone. The best results (conversion: 94%, ee: 71%) were obtained with benzylamine grafted onto poly(GMA-co-EDMA) (30/70 % wt/wt). 相似文献