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1.
Prof. Dr. Yujiro Hayashi Akira Takikawa Seitaro Koshino Keiichi Ishida 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(44):10319-10322
A three-pot synthetic method that features the use of an organocatalyst as the key step was developed for the preparation of biaryl atropisomers. The first reaction is an asymmetric domino Michael–Henry reaction catalyzed by diphenylprolinol silyl ether to afford the substituted nitrocyclohexanecarbaldehyde with four stereogenic centers and one defined configuration of a stereogenic axis with excellent enantioselectivity. Removal of the central chirality from the domino products afforded biaryl atropisomers having axial chirality with excellent enantioselectivity. 相似文献
2.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(51):16526-16530
The first phosphoric acid catalyzed direct arylation of 2‐naphthylamines with iminoquinones for the atroposelective synthesis of axially chiral biaryl amino alcohols has been developed. This reaction constitutes a highly functional‐group‐tolerant route for the rapid construction of enantioenriched axially chiral biaryl amino alcohols, and is a rare example of 2‐naphthylamines acting as nucleophiles in an organocatalytic enantioselective transformation. Furthermore, the products, which feature various halogen atoms, provide access to structurally diverse axially chiral amino alcohols through further transformations. 相似文献
3.
Access to P‐ and Axially Chiral Biaryl Phosphine Oxides by Enantioselective CpxIrIII‐Catalyzed C−H Arylations 下载免费PDF全文
Yun‐Suk Jang Dr. Łukasz Woźniak Dr. Julia Pedroni Prof. Dr. Nicolai Cramer 《Angewandte Chemie (International ed. in English)》2018,57(39):12901-12905
An enantioselective C?H arylation of phosphine oxides with o‐quinone diazides catalyzed by an iridium(III) complex bearing an atropchiral cyclopentadienyl (Cpx) ligand and phthaloyl tert‐leucine as co‐catalyst is reported. The method allows access to a) P‐chiral biaryl phosphine oxides, b) atropo‐enantioselective construction of sterically demanding biaryl backbones, and also c) selective assembly of axial and P‐chiral compounds in excellent yields and diastereo‐ and enantioselectivities. Enantiospecific reductions provide monodentate chiral phosphorus(III) compounds having structures and biaryl backbones with proven importance as ligands in asymmetric catalysis. 相似文献
4.
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
5.
《中国化学》2018,36(2):153-156
A series of structurally novel P‐chiral biaryl bisphosphorus ligands L1‐L5 (BABIBOPs) are developed, providing high efficiency for the first time in palladium‐catalyzed asymmetric hydrogenation of β‐aryl and β‐alkyl substituted β‐keto esters. With the Pd‐ L3 (iPr‐BABIBOP) catalyst, a series of chiral β‐hydroxyl carboxylic esters are formed in excellent enantioselectivities (up to>99% ee) and yields at catalyst loading as low as 0.01 mol%. 相似文献
6.
Biocatalytic Dynamic Kinetic Resolution for the Synthesis of Atropisomeric Biaryl N‐Oxide Lewis Base Catalysts 下载免费PDF全文
Dr. Samantha Staniland Dr. Ralph W. Adams Dr. Joseph J. W. McDouall Dr. Irene Maffucci Dr. Alessandro Contini Dr. Damian M. Grainger Prof. Nicholas J. Turner Prof. Jonathan Clayden 《Angewandte Chemie (International ed. in English)》2016,55(36):10755-10759
Atropisomeric biaryl pyridine and isoquinoline N‐oxides were synthesized enantioselectively by dynamic kinetic resolution (DKR) of rapidly racemizing precursors exhibiting free bond rotation. The DKR was achieved by ketoreductase (KRED) catalyzed reduction of an aldehyde to form a configurationally stable atropisomeric alcohol, with the substantial increase in rotational barrier arising from the loss of a bonding interaction between the N‐oxide and the aldehyde. Use of different KREDs allowed either the M or P enantiomer to be synthesized in excellent enantiopurity. The enantioenriched biaryl N‐oxide compounds catalyze the asymmetric allylation of benzaldehyde derivatives with allyltrichlorosilane. 相似文献
7.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(17):4855-4859
The palladium‐catalyzed asymmetric synthesis of enone‐based atropisomers from 2‐iodo‐3‐methylcyclohex‐2‐enones and aryl boronic acid is reported. BoPhoz‐type phosphine–aminophosphine ligands showed superior enantioselectivity over other ligands. These cyclohexenone‐based atropisomers are useful compounds for further elaboration. The divergent synthesis of biaryl atropisomers with different ortho substituents was demonstrated. 相似文献
8.
Jia-Hong Wu Dr. Jian-Ping Tan Jia-Yan Zheng Jiajia He Prof. Dr. Zhenlei Song Prof. Dr. Zhishan Su Prof. Dr. Tianli Wang 《Angewandte Chemie (International ed. in English)》2023,62(13):e202215720
Given the comparatively lower rotational barriers, the catalytic asymmetric construction of axially chiral biaryl structures, especially those containing a five-membered heterocycle, still remains a challenge. Herein, we described a general and modular protocol to access atropisomeric arylpyrazole scaffolds containing a phosphorus unit by a dipeptide phosphonium salt catalyzed reaction involving an oxidative central-to-axial chirality conversion. This reaction features excellent yields and enantioselectivities, broad substrate scope, and a low catalyst loading, delivering axially chiral phosphine compounds. 相似文献
9.
Aromatic Amide‐Derived Non‐Biaryl Atropisomers as Highly Efficient Ligands in Silver‐Catalyzed Asymmetric Cycloaddition Reactions 下载免费PDF全文
Xing‐Feng Bai Tao Song Dr. Zheng Xu Prof. Chun‐Gu Xia Wei‐Sheng Huang Prof. Dr. Li‐Wen Xu 《Angewandte Chemie (International ed. in English)》2015,54(17):5255-5259
The synthesis of a series of aromatic amide‐derived non‐biaryl atropisomers with a phosphine group and multiple stereogenic centers is reported. The novel phosphine ligands exhibit high diastereo‐ and enantioselectivities (up to >99:1 d.r., 95–99 % ee) as well as yields in the silver‐catalyzed asymmetric [3+2] cycloaddition of aldiminoesters with nitroalkenes, which provides a highly enantioselective strategy for the synthesis of optically pure nitro‐substituted pyrrolidines. In addition, the experimental results with regard to the carbon stereogenic center as well as the amide stereochemistry confirmed the potential of hemilabile atropisomers as chiral ligand in catalytic asymmetric [3+2] cycloaddition reaction. 相似文献
10.
Enantiodivergent Atroposelective Synthesis of Chiral Biaryls by Asymmetric Transfer Hydrogenation: Chiral Phosphoric Acid Catalyzed Dynamic Kinetic Resolution 下载免费PDF全文
Prof. Dr. Keiji Mori Tsubasa Itakura Prof. Dr. Takahiko Akiyama 《Angewandte Chemie (International ed. in English)》2016,55(38):11642-11646
Reported herein is an enantiodivergent synthesis of chiral biaryls by a chiral phosphoric acid catalyzed asymmetric transfer hydrogenation reaction. Upon treatment of biaryl lactols with aromatic amines and a Hantzsch ester in the presence of chiral phosphoric acid, dynamic kinetic resolution (DKR) involving a reductive amination reaction proceeded smoothly to furnish both R and S isomers of chiral biaryls with excellent enantioselectivities by proper choice of hydroxyaniline derivative. This trend was observed in wide variety of substrates, and various chiral biphenyl and phenyl naphthyl adducts were synthesized with satisfactory enantioselectivities in enantiodivergent fashion. The enantiodivergent synthesis of synthetically challenging, chiral o‐tetrasubstituted biaryls were also accomplished, and suggests high synthetic potential of the present method. 相似文献
11.
Gerhard Bringmann Rainer Walter Ralf Weirich 《Angewandte Chemie (International ed. in English)》1990,29(9):977-991
The preparation and utilization of specific biaryl systems, particularly those which suffer hindered rotation, is a demanding goal not only in the synthesis of natural products and Pharmaceuticals, but also for example in the discovery of new reagents for asymmetric synthesis. This article will attempt to provide a topical review of modern, efficient processes for the specific preparation of biaryls. This appears to be of particular urgency, since, under the pressure of continually increasing demand, a wealth of new or modified synthetic approaches to the ever more important biaryl systems has been realized in recent years. The high standard which has been reached in this field is impressively demonstrated by regio- and stereoselective syntheses of important biaryl natural products such as steganone, ancistrocladine, ancistrocladisine, and dioncophylline A. Besides the utilization of asymmetric induction in the actual coupling step, the thermodynamically or kinetically controlled torsion of biaryl axes belongs to the most important concepts discussed. 相似文献
12.
Construction of Axial Chirality by Rhodium‐Catalyzed Asymmetric Dehydrogenative Heck Coupling of Biaryl Compounds with Alkenes 下载免费PDF全文
Jun Zheng Prof. Dr. Shu‐Li You 《Angewandte Chemie (International ed. in English)》2014,53(48):13244-13247
Enantioselective construction of axially chiral biaryls by direct C? H bond functionalization reactions has been realized. Novel axially chiral biaryls were synthesized by the direct C? H bond olefination of biaryl compounds, using a chiral [Cp*RhIII] catalyst, in good to excellent yields and enantioselectivities. The obtained axially chiral biaryls were found as suitable ligands for rhodium‐catalyzed asymmetric conjugate additions. 相似文献
13.
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
14.
Heterogeneous Rhodium‐Catalyzed Aerobic Oxidative Dehydrogenative Cross‐Coupling: Nonsymmetrical Biaryl Amines 下载免费PDF全文
Dr. Kenji Matsumoto Prof. Masahiro Yoshida Prof. Mitsuru Shindo 《Angewandte Chemie (International ed. in English)》2016,55(17):5272-5276
The first heterogeneously catalyzed oxidative dehydrogenative cross‐coupling of aryl amines is reported herein. 2‐Naphthylamine analogues were reacted with various electron‐rich arenes using a heterogeneous Rh/C catalyst under mild aerobic conditions, thus affording nonsymmetrical biaryl amines in excellent yields with high selectivities. This reaction provides a mild, operationally simple, and efficient approach for the synthesis of biaryls which are important to pharmaceutical and materials chemistry. 相似文献
15.
Asymmetric Suzuki–Miyaura Cross‐Coupling for the Synthesis of Chiral Biaryl Compounds as Potential Monophosphine Ligands 下载免费PDF全文
Yan‐Na Ma Prof. Shang‐Dong Yang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(18):6673-6677
Efficient asymmetric Suzuki–Miyaura coupling reactions have been employed for the first time to synthesize chiral biaryl compounds with phosphinate groups as chiral auxiliaries. A series of functionalized chiral biaryls are thereby synthesized in excellent yields and good diastereoselectivities (up to >95:5 d.r.) and axially chiral monophosphorus ligands are obtained through further functionalizations. 相似文献
16.
Mitsuhiro Okimoto Takashi Yoshida Masayuki Hoshi Tomohito Chiba Kei Maeo 《合成通讯》2013,43(21):3134-3139
Various biaryl methanols were electrooxidized into the corresponding biaryl ketones in good yields and under very mild reaction conditions. Because of the relatively high oxidation potential, bulky structure, and somewhat poor solubility, biaryl methanols do not readily undergo direct electrooxidative transformations as a synthetic step toward the corresponding biaryl ketones. Herein, we report the successful indirect electrooxidation of secondary biaryl methanols featuring the use of a slight excess amount of KI (1.2 equivalents, relative to the substrate) in MeOH. 相似文献
17.
Jeffrey Buter Dorus Heijnen Carlos Vila Valentín Hornillos Edwin Otten Massimo Giannerini Adriaan J. Minnaard Ben L. Feringa 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(11):3684-3688
A palladium‐catalyzed direct synthesis of symmetric biaryl compounds from aryl halides in the presence of tBuLi is described. In situ lithium–halogen exchange generates the corresponding aryl lithium reagent, which undergoes a homocoupling reaction with a second molecule of the aryl halide in the presence of the palladium catalyst (1 mol %). The reaction takes place at room temperature, is fast (1 h), and affords the corresponding biaryl compounds in good to excellent yields. The application of the method is demonstrated in an efficient asymmetric total synthesis of mastigophorene A. The chiral biaryl axis is constructed with an atropselectivity of 9:1 owing to catalyst‐induced remote point‐to‐axial chirality transfer. 相似文献
18.
Palladium‐Catalyzed,tert‐Butyllithium‐Mediated Dimerization of Aryl Halides and Its Application in the Atropselective Total Synthesis of Mastigophorene A 下载免费PDF全文
Jeffrey Buter Dorus Heijnen Dr. Carlos Vila Dr. Valentín Hornillos Dr. Edwin Otten Dr. Massimo Giannerini Prof. Dr. Adriaan J. Minnaard Prof. Dr. Ben L. Feringa 《Angewandte Chemie (International ed. in English)》2016,55(11):3620-3624
A palladium‐catalyzed direct synthesis of symmetric biaryl compounds from aryl halides in the presence of tBuLi is described. In situ lithium–halogen exchange generates the corresponding aryl lithium reagent, which undergoes a homocoupling reaction with a second molecule of the aryl halide in the presence of the palladium catalyst (1 mol %). The reaction takes place at room temperature, is fast (1 h), and affords the corresponding biaryl compounds in good to excellent yields. The application of the method is demonstrated in an efficient asymmetric total synthesis of mastigophorene A. The chiral biaryl axis is constructed with an atropselectivity of 9:1 owing to catalyst‐induced remote point‐to‐axial chirality transfer. 相似文献
19.
Isoplagiochin D is a ring‐strained macrocyclic bisbibenzylis, which showed stable axial chirality in one biaryl structure, and semistable axial chirality in the other biaryl moiety. We reported here an unprecedented example for the catalytically asymmetric synthesis of ring‐strained atropisomers via Pd‐catalyzed macrocyclization between benzyl halides and carbenes. This newly developed Pd‐catalyzed asymmetric macrocyclization protocol enabled us a quick synthesis of isoplagiochin D in a highly enantioselective manner. 相似文献
20.
The design of new chiral ligands is the key in the development of transition metal catalyzed asymmetric synthesis. Many chiral diphosphine ligands have been prepared and applied in asymmetric catalytic reactions with excellent enantioselectivities. Among the chiral diphosphine ligands that have been reported, the atropisomeric C2-symmetric phosphines with a biaryl scaffold initiated by Noyori and co-workers with BINAP were found to have the widest application in the transition metal catalyze… 相似文献