Download or read book Development of Effective Chiral Ligands for Catalytic Asymmetric Hydrogenation written by Weicheng Zhang and published by . This book was released on 2009 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Chiral Ligands written by Montserrat Diéguez and published by CRC Press. This book was released on 2021-05-12 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many new drugs on the market are chiral compounds, that is, they can exist in two non-superimposable mirror-image forms. Asymmetric catalysis encompasses a large variety of processes for obtaining such compounds. The performance of the catalyst in those processes largely depends on the ligand that makes up the catalyst. This book describes the most relevant ligand libraries for some key processes, including an overview of the state of art and the key mechanistic aspects that favor a high catalytic performance. Key Features: The book presents historical content from the time of discovery for each family of ligands. Provides a description of the synthetic route and the ligand library's application in various catalytic asymmetric reactions Suitable as supplementary reading for courses targeting the design, synthesis and application of chiral catalysts, asymmetric catalysis and sustainable production Edited by a distinguished scientist in the field, the book has a diverse audience including research groups in homogeneous catalysis, particularly asymmetric transformations

Download or read book Privileged Chiral Ligands and Catalysts written by Qi-Lin Zhou and published by John Wiley & Sons. This book was released on 2011-02-10 with total page 670 pages. Available in PDF, EPUB and Kindle. Book excerpt: Catalytic asymmetric synthesis has been one of the most active research areas in chemistry (Nobel Prize in 2001). The development of efficient chiral catalysts plays a crucial role in asymmetric catalysis. Although many chiral ligands/catalysts have been developed in the past decades, the most efficient catalysts are derived from a few core structures, called "privileged chiral catalysts". This ultimate "must have" and long awaited reference for every chemist working in the field of asymmetric catalysis starts with the core structure of the catalysts, explaining why a certain ligand or catalyst is so successful. It describes in detail the history, the basic structural characteristics, and the applications of these "privileged catalysts". This novel presentation provides readers with a much deeper insight into the topic and makes it a must-have for organic chemists, catalytic chemists, chemists working with/on organometallics, chemists in industry, and libraries. From the contents: * BINAP * Bisphosphacycles - From DuPhos and BPE to a Diverse Set of Broadly Applied Ligands * Josiphos Ligands: From Discovery to Technical Applications * Chiral Spiro Ligands * Chiral Bisoxazoline Ligands * PHOX Ligands * Chiral Salen Complexes * BINOL * TADDOLate Ligands * Cinchona Alkaloids * Proline Derivatives

Download or read book Catalytic Asymmetric Synthesis written by Iwao Ojima and published by John Wiley & Sons. This book was released on 2013-03-14 with total page 1043 pages. Available in PDF, EPUB and Kindle. Book excerpt: Praise for the previous editions "An excellent text . . . will no doubt provide the benchmark for comparative works for many years." —Journal of the American Chemical Society "An excellent state-of-the-art compilation of catalytic asymmetric chemistry . . . should be included in any chemistry reference collection." —Choice "This is a tremendous resource and an excellent read. I recommend immediate purchase." —Perkin Transactions Since this important work was first published in 1993, the field of catalytic asymmetric synthesis has grown explosively, spawning effective new methods for obtaining enantiomerically pure compounds on a large scale and stimulating new applications in diverse fields—from medicine to materials science. Catalytic Asymmetric Synthesis, Third Edition addresses these rapid changes through contributions from highly recognized world leaders in the field. This seminal text presents detailed accounts of the most important catalytic asymmetric reactions known today, and discusses recent advances and essential information on the initial development of certain processes. An excellent working resource for academic researchers and industrial chemists alike, the Third Edition features: Six entirely new chapters focusing on novel approaches to catalytic asymmetric synthesis including non-conventional media/conditions, organocatalysis, chiral Lewis and Bronsted acids, CH activation, carbon-heteroatom bond-forming reactions, and enzyme-catalyzed asymmetric synthesis A new section focusing on the important new reaction, asymmetric metathesis, in carbon-carbon bond-forming reactions Updated chapters on hydrogenation, carbon-carbon bond-forming reactions, hydrosilylations, carbonylations, oxidations, amplifications and autocatalysis, and polymerization reactions Retaining the best of its predecessors but now thoroughly up to date, Catalytic Asymmetric Synthesis, Third Edition serves as an excellent desktop reference and text for researchers and students from the upper-level undergraduates through experienced professionals in industry or academia.

Download or read book Asymmetric Catalysis from a Chinese Perspective written by Shengming Ma and published by Springer Science & Business Media. This book was released on 2011-07-06 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: Qi-Lin Zhou and Jian-Hua Xie: Chiral Spiro Catalysts.- Fuk Loi Lam, Fuk Yee Kwong and Albert S. C. Chan: Chiral Phosphorus Ligands with Interesting Properties and Practical Applications.- Jiang Pan, Hui-Lei Yu, Jian-He Xu, Guo-Qiang Lin: Advances in Biocatalysis: Enzymatic Reactions and Their Applications.- Mei-Xiang Wang: Enantioselective Biotransformations of Nitriles.- Man Kin Wong, Yiu Chung Yip and Dan Yang: Asymmetric Epoxidation Catalyzed by Chiral Ketones.- W. J. Liu, N. Li and L. Z. Gong: Asymmetric Organocatalysis.- Qing-Hua Fan and Kuiling Ding: Enantioselective Catalysis with Structurally Tunable Immobilized Catalysts.- Chang-Hua Ding, Xue-Long Hou: Transition Metal-Catalyzed Asymmetric Allylation.- Jian Zhou and Yong Tang: Enantioselective Reactions with Trisoxazolines.- Xiang-Ping Hu, Duo-Sheng Wang, Chang-Bin Yu, Yong-Gui Zhou, and Zhuo Zheng: Adventure in Asymmetric Hydrogenation: Synthesis of Chiral Phosphorus Ligands and Asymmetric Hydrogenation of Heteroaromtics.

Download or read book Handbook of Asymmetric Heterogeneous Catalysis written by Kuiling Ding and published by John Wiley & Sons. This book was released on 2008-10-20 with total page 467 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this most up-to-date handbook each chapter contains a general introduction, followed by the principles of the immobilization and, finally, applications. In this way, it covers the most important approaches currently employed for the heterogenization of chiral catalysts, including data tables, applications, reaction types and literature citations. For chemists in both academia and industry as well as those working in the fine chemical and pharmaceutical industry.

Download or read book Chiral Ferrocenes in Asymmetric Catalysis written by Li-Xin Dai and published by John Wiley & Sons. This book was released on 2010-02-01 with total page 433 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book meets the long-felt need for a reference on ferrocenes with the focus on catalysis. It provides a thorough overview of the synthesis and characterization of different types of chiral ferrocene ligands, their application to various catalytic asymmetric reactions, and versatile chiral materials as well as drug intermediates synthesized from them. Written by the "who's who" of ferrocene catalysis, this is a guide to the design of new ferrocene ligands and synthesis of chiral synthetic intermediates, and will thus be useful for organic, catalytic and synthetic chemists working in academia, industrial research or process development.

Download or read book Asymmetric Hydrogenation and Transfer Hydrogenation written by Virginie Ratovelomanana-Vidal and published by John Wiley & Sons. This book was released on 2021-04-06 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Asymmetric Hydrogenation and Transfer Hydrogenation Discover the latest developments in homogeneous asymmetric (transfer) hydrogenation with this up-to-date resource Asymmetric Hydrogenation and Transfer Hydrogenation delivers a current and cutting-edge investigation of homogenous asymmetric hydrogenation and transfer hydrogenation reactions of prochiral substrates by using organometallic catalysts (like ruthenium, rhodium, iridium, iron, and copper) and organic catalysts. Distinguished researchers and editors Virginie Ratovelomanana-Vidal and Phannarath Phansavath also offer readers a comprehensive walkthrough of substituted ketones through dynamic kinetic resolution, as well a presentation of the mechanisms and application of asymmetric hydrogenation reactions to the synthesis of biologically relevant compounds. The book comprehensively details its complex subject matter clearly and plainly and covers everything from catalyst development and reactions to mechanisms and applications in academia and industry. The papers included within come from many of the leading voices in their respective fields and represent the newest and best research available today. Compiled for researchers and private-industry chemists alike, Asymmetric Hydrogenation and Transfer Hydrogenation also discusses a wide variety of other topics like: A discussion of the development of chiral metal catalysts for asymmetric transfer hydrogenation Several examinations of asymmetric transfer hydrogenation of a variety of chemical groups, including ketones, aryl and heteroaryl ketones, substituted ketones, and heteroaromatic compounds, alkenes, and imines An exploration of the mechanism of asymmetric hydrogenation and continuous flow asymmetric hydrogenation A full and thorough treatment of the industrial applications of asymmetric hydrogenation Perfect for catalytic chemists, chemists working on or with organometallics, organic chemists, natural product chemists, pharmaceutical chemists, medicinal chemists, and industrial chemists, Asymmetric Hydrogenation and Transfer Hydrogenation also belongs on the bookshelves of research and university institutes and libraries who wish to expand their selection on a topic fundamental to organic synthesis.

Download or read book The Design of New Substrates and Ligands for Rhodium Catalyzed Asymmetric Hydrogenation written by Tian Sun and published by . This book was released on 2013 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: Asymmetric hydrogenation is a significant research field in modern catalytic organic synthesis. In the past 50 years, the design of catalysts and substrates has been widely studied. A great number of phosphorus ligands for asymmetric hydrogenation have been developed. Three generations of catalysts have been reported by a number of scientists. The asymmetric hydrogenation becomes more and more efficient and applicable. High enantioselectivities and activities have been achieved. The design of substrates also makes significant progresses. Many successful examples have been reported in asymmetric hydrogenation of olefins, ketones, and imines. In chapter one, the development of phosphorus ligands is reported. The characters of phosphorus ligands are discussed and compared. Examples of representative catalysts are listed. The asymmetric hydrogenation of different substrates is also summarized and discussed. In chapter two, asymmetric hydrogenation of Îł-dehydroamino ketones catalyzed by a rhodium-chiral phosphorus ligand complex (up to 99% ee, 1000 TON) is reported. This reaction represents an efficient approach to chiral Îł-amino ketones. The reduction of Îł-amino ketones catalyzed by Palladium on carbon (Pd/C) leads to amphetamine precursors with quantitative yield and no significant enantioselectivity loss. In chapter three, high enantioselectivities (up to 99% ee) have been observed for the catalytic asymmetric hydrogenation of the Îł-ketone enol acetates. DuanPhos has been proved to be the most effective ligand for this reaction. High yield and enantioselectivity of the asymmetric hydrogenation of the Îł-ketone enol acetates demonstrates a feasible synthetic route to important pharmaceutical building blocks: Îł-hydroxy ketones. In chapter four, a series of new chiral secondary phosphine oxide (SPO) ligands are reported. Compared with traditional bisphosphine ligands, the SPO ligands are air stable, and have shorter synthetic routes. However, poor to moderate results are obtained using the new chiral SPO ligands. The study of SPO ligands still has many unsolved problems. The potential applications and challenges of SPO ligands are also discussed in chapter four.

Download or read book Metal Catalyzed Asymmetric Hydrogenation Evolution and Prospect written by and published by Academic Press. This book was released on 2021-11-23 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal-Catalyzed Asymmetric Hydrogenation, Volume 68 in the Advances in Catalysis series, fills the gap between journal papers and textbooks across diverse areas of catalysis research. For more than 60 years, this series has recorded and presented the latest progress in the field of catalysis, giving the scientific community comprehensive and authoritative reviews. Chapters in this new release include Asymmetric hydrogenation of functionalized olefins, Asymmetric hydrogenation of unfunctionalized olefins or with poorly coordinative groups, Asymmetric hydrogenation of imines, Asymmetric hydrogenation of ketones, Asymmetric hydrogenation in industry, and Computational insights into metal-catalyzed asymmetric hydrogenation. This series is an invaluable and comprehensive resource for chemical engineers and chemists working in the field of catalysis in both academia and industry, with this release focusing on solid acids, surface acidity and heterogeneous acid catalysis. Contains authoritative reviews written by experts in the field Explores topics that reflect progress in the field, such as catalyst synthesis, catalyst characterization, catalytic chemistry, reaction engineering, computational chemistry and physics Provides insightful and critical articles that are fully edited to suit various backgrounds

Download or read book Development and Evaluation of Chiral Catalysts for Asymmetric C C and C H Bond forming Reactions written by Christian Ebner and published by Cuvillier Verlag. This book was released on 2012-03-05 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work was dedicated to the development and evaluation of new chiral catalysts for asymmetric C-C and C-H bond forming reactions. In the first part of the thesis an ESI-MS screening method is described, which allows the determination of a chiral catalyst´s selectivity in the palladium catalyzed asymmetric allylic alkylation by testing its racemic form. The value of this new method was demonstrated when different new aryl-PHOX-type ligands, which are not easily accessible in their enantiopure form, were evaluated. In the second part new PHOX-type ligands were tested in the iridium-catalyzed asymmetric hydrogenation of different unsaturated compounds. Although low activities and selectivities were found in most cases, one ligand showed promising results in the hydrogenation of allylic alcohols and imines. Furthermore air- and moisture-stable secondary phosphine oxide (SPO) containing bidentate ligands were tested in the palladium-catalyzed asymmetric allylic alkylation reaction. SPO,N-ligands bearing a PHOX type backbone were inactive in this transformation as they tend to form inactive palladium-bis-ligand complexes. SPO,P ligands however, were able to promote the desired reaction in a highly selective fashion although only low activities were found. During this work as well a new organo-catalyst, based on the structure of 2,3-dihydrobenzo[1,4]oxazine, was developed which allows for the asymmetric organo-catalyzed transfer-hydrogenation of α,β-unsaturated aldehydes. This catalyst was able to reduce for the first time β, β-diaryl acrylaldehydes with very good activities and high enantioselectivities. Moreover an ESI-MS based mechanistic study on the tripeptide catalyzed conjugate addition reaction of aldehydes to nitroolefins was carried out. By this all reaction intermediates postulated for an enamine mechanism have been detected. Furthermore the attack of the enamine onto the nitroolefin was found to be the selectivity determining step in this process. The last part of this work aimed for the asymmetric α -allylation of carbonyl compounds by a tandem-catalysis approach. An intensive screening of both the organo-catalyst and the palladium-ligand led to reaction conditions which allowed for the selective mono-allylation of ketones in high yields. The formation of a quaternary center by α -allylation of α -branched aldehydes was also achieved. However, only low enantiomeric excesses were obtained in this transformation for the different catalyst systems tested.

Download or read book Fundamentals of Asymmetric Catalysis written by Patrick J. Walsh and published by University Science Books. This book was released on 2009-01-02 with total page 692 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work describes the essential aspects of enantioselective catalysis, with chapters organised by concept rather than by reaction type. Each concept is supported by examples to give the reader broad exposure to a wide range of catalysts, reactions and reaction mechanisms.

Download or read book New Subtrate Classes in Iridium Catalyzed Asymmetric Hydrogenation written by Maurizio Bernasconi and published by Cuvillier Verlag. This book was released on 2014-01-30 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main aim of the research presented in this thesis was to expand the substrate scope of the iridium-catalyzed asymmetric hydrogenation, which represents an extremely useful methodology for the enantioselective synthesis of chiral molecules.While this chemistry has been developed and investigated mainly for the hydrogenation of unfunctionalized olefins, so far only little attention has been given to functionalized olefins. Therefore, the different research projects presented in this thesis dealt with the application of iridium catalysts to the reduction of particularly valuable substrates that are difficult to hydrogenate enantioselectively with other methods. The first chapter of this thesis gives a general introduction on asymmetric hydrogenation and the role of iridium catalysts in this context. The following two chapters deal with the investigation of new substrates in the iridium-catalyzed asymmetric hydrogenation using various N,Pligands developed in the Pfaltz group,and give an account of the superior results that have been obtained with such catalysts compared to thoserepresenting the state-of-the-art. In particular, chapter twoconcerns the reduction of vinylsilanes, for which the judicious choice of the best catalyst for each specific substrate was required to achieve good results in term of both chemical and optical yield. On the contrary, a pyridinyl phosphitine bearing a 2,6-difluorophenyl group on the oxazoline ringwas best suited for a broad array of 2-alkyl- and aryl- substituted maleic acid dimethyldiester, as reported in chapter three. Such process turned out to be enantioconvergent, allowing the hydrogenation of mixtures of maleates and fumarates in high enantiomeric excesses. In chapter fourthe deployment of environmentally friendly solvents such as THF and 2-MeTHF in the iridium-catalyzed asymmetric hydrogenation of 3,3-disubstituted allylic alcohols is described. Finally, chapter five of this dissertation deals with the development of new NHC ligands for the iridium-catalyzed asymmetric hydrogenation of acid-labile substrates such as tert-butyloxycarbonyl protected allylic alcohols. Experimental details and characterization of the substances discussed in the main body of this manuscript is reported in the experimental section that constitutes chapter six.

Download or read book Chiral Sulfur Ligands written by Hélène Pellissier and published by Royal Society of Chemistry. This book was released on 2009 with total page 403 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this book is to show the high potential of chiral sulfur-containing ligands to promote numerous asymmetric catalytic transformations. These ligands can now be recognised as real competitors to the more usual phosphorus- or nitrogen-containing ligands.

Download or read book Chiral Phosphorous Based Ligands in Earth Abundant Transition Metal Catalysis written by Junliang Zhang and published by Elsevier. This book was released on 2023-05-27 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chiral Phosphorous Based Ligands in Earth-Abundant Transition Metal Catalysis summarizes the most significant progress in the field of chiral phosphine ligand chemistry and a broad range of earth-abundant transition metal/chiral phosphine ligand-catalyzed enantioselective transformations. The book provides an authoritative and in-depth understanding of important topics about asymmetric catalysis based on earth-abundant transition metals/chiral phosphine ligands, making it ideal for organic chemistry researchers working in the field of asymmetric catalysis, synthetic methodologies and total synthesis.The development of new chiral phosphine ligands to achieve precise stereo control in many earth-abundant transition metal-catalyzed reactions is a very important field in organic synthesis, materials science and medicinal chemistry. The asymmetric synthesis promoted by transition metal/chiral phosphine ligands provides one of the most ideal ways to produce valuable optically active chemicals. Includes a discussion of state-of-the-art asymmetric organic reactions mediated by earth-abundant transition metals and chiral phosphine ligands Features the progress and the prospect of chiral phosphine ligands in asymmetric transition metal catalysis Covers the asymmetric reactivity modes of earth-abundant transition metals and phosphine ligands

Download or read book Developing P Stereogenic Phosphine Ligand for Transition Metal Catalyzed Asymmetric Hydrogenation written by Heng Wang and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation focusses on the discussion of how empirical ligand design works on the development of chiral pincer ligands in the field of asymmetric hydrogenation. Although the design art of bisphosphine ligands was well-established, this empirical guide for pincer ligand design is still ambiguous. Developing a ligand design guide based on the nature of metals enables synthetic chemists to improve the catalytic performance without investing large numbers of time, develop highly efficient catalysts for industrial uses, or explore new areas and mechanistic insights. Learning from the history of chiral pincer ligand development, over 14 categories of pincer ligands were reported according to the coordinating atoms by the time that this dissertation was prepared. Firstly, the ligand design and relevant catalytic performance of different ligand categories were summarized and discussed in prevalent noble metal catalysis such as Ru(II), Ir(III). Based on the nature of Fe(II) with respect to noble metals, a novel PNP-type ligand HengPNP (L) was designed and successfully synthesized. Empirical design perspectives were discussed, and the ligand was characterized by NMR, HRMS. Its corresponding Fe(II) complex was studied by X-ray crystallographic technique. However, the Fe(II) carbonyl complex was thermodynamically unstable under decent pressure. To better understand the catalytic performance and enantioselectivity of HengPNP(L), its corresponding Ir(III) complex was employed in the asymmetric hydrogenation of various ketone substrates. A C-H bond activation Ir(III) compound was successfully isolated. The Ir(III)/HengPNP was efficient on the asymmetric hydrogenation of orthosubstituted benzophenones with excellent ee and up to 500 TON. The catalyst was superior on the hydrogenation of bis-ortho-substituted benzophenones, excellent ee was achieved over the state-of-the-art Ir/f-amphox. DFT studies was conducted to shed light on the enantio-induction model of Ir/HengPNP. A novel enantio-induction mechanism was established-the change of rotation energy of ketone substrate under the steric pressure from rigid Ir/HengPNP, was responsible for the enantioselectivity. IrH/NH bifunctional mechanism was proposed for this protocol.

Download or read book Heterogeneous Enantioselective Hydrogenation written by Evgenii Klabunovskii and published by Springer Science & Business Media. This book was released on 2007-05-22 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heterogeneous Enantioselective Hydrogenation: Theory and Practice reviews the development of enantioselective hydrogenation reaction catalysts. It looks at the first relatively ineffective catalysts right through to modern highly effective enantioselective catalytic systems, comparable in their efficiency to chiral metal complexes and enzymatic systems. The book begins with a summary of the first work on heterogeneous metal catalysts, which showed only the principal possibilities of enantioselective reactions. It then elaborates on metal catalysts which have enantioselectivities close to 100%. Finally, the practical utilization of chiral catalytic systems in processes of hydrogenation is described. The alpha- and beta-hydroxy carboxylic acid esters produced are precursors for manufacturing many synthones used for medicines as well as for monomers used for biodegradable polyesters, both of which have important practical applications. The volume summarizes more than 800 scientific papers in the field of enantioselective catalytic hydrogenation reactions, mainly those using heterogeneous metal catalysts. It provides detailed explanations of special techniques for the preparation of effective dissymmetric catalysts which provide highly efficient catalytic systems.