Download or read book Design Synthesis and Characterization of New Chiral Ligands and Mechanistic Investigations Into Catalytic Enantioselective Hydrogenation Reactions written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 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 with total page 0 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.
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 Artificial Metalloenzymes and MetalloDNAzymes in Catalysis written by Montserrat Diéguez and published by John Wiley & Sons. This book was released on 2018-02-21 with total page 431 pages. Available in PDF, EPUB and Kindle. Book excerpt: An important reference for researchers in the field of metal-enzyme hybrid catalysis Artificial Metalloenzymes and MetalloDNAzymes in Catalysis offers a comprehensive review of the most current strategies, developed over recent decades, for the design, synthesis, and optimization of these hybrid catalysts as well as material about their application. The contributors—noted experts in the field—present information on the preparation, characterization, and optimization of artificial metalloenzymes in a timely and authoritative manner. The authors present a thorough examination of this interesting new platform for catalysis that combines the excellent selective recognition/binding properties of enzymes with transition metal catalysts. The text includes information on the various applications of metal-enzyme hybrid catalysts for novel reactions, offers insights into the latest advances in the field, and contains an informative perspective on the future: Explores the development of artificial metalloenzymes, the modern and strongly evolving research field on the verge of industrial application Contains a comprehensive reference to the research area of metal-enzyme hybrid catalysis that has experienced tremendous growth in recent years Includes contributions from leading researchers in the field Shows how this new catalysis combines the selective recognition/binding properties of enzymes with transition metal catalysts Written for catalytic chemists, bioinorganic chemists, biochemists, and organic chemists, Artificial Metalloenzymes and MetalloDNAzymes in Catalysis offers a unique reference to the fundamentals, concepts, applications, and the most recent developments for more efficient and sustainable synthesis.
Download or read book Design Synthesis and Evaluation of Chiral Nonracemic Ligands and Catalysts for Asymmetric Synthesis written by Michael P. A. Lyle and published by . This book was released on 2005 with total page 680 pages. Available in PDF, EPUB and Kindle. Book excerpt: The work described in this thesis concerns the design, synthesis and evaluation of new chiral nonracemic ligands and catalysts for use in asymmetric reactions. A series of chiral nonracemic chloroacetals were prepared from 2-chloro-4- methyl-6,7-dihydro-5H-[l]pyrindine-7-one and a variety of C2-symmetric and chiral nonracemic 1,2-ethanediols (R = Me, i-Pr and Ph). These chloroacetals were further elaborated, in a modular fashion, to provide a series of chiral ligands and catalysts. A new class of C2-symmetric 2,2'-bipyridyl ligands were prepared in one step fiom the chloroacetals via a nickel(0)-mediated homo-coupling reaction. These ligands were then evaluated as chiral directors in copper@)-catalyzed asymmetric cyclopropanation reactions of styrene and diazoesters (up to 44% ee). A chiral pyridine N-oxide and a C2-symmetric 2,2'-bipyridyl N, N'-dioxide were also prepared by direct oxidation of the corresponding pyridine and the 2,2'-bipyridine, respectively. These chiral N-oxides were evaluated as chiral catalysts in desymmeterization reactions of cis-stilbene oxide (up to 20% ee). A series of pyridylphosphine ligands (P, N-ligands) were subsequently prepared in two steps from the chloroacetals via a Suzuki coupling reaction with orthofluorophenylboronic and on subsequent displacement of the fluoride with the potassium anion of diphenylphosphine. These ligands were then evaluated in palladium-catalyzed asymmetric allylic substitution reactions of racemic 3-acetoxy-l,3-diphenyl-1-propene with dimethyl malonate. Optimization of the reaction conditions resulted in the formation of the alkylated product in excellent yield (91%) and in high enantiomeric excess (90%). A related chiral nonracemic and C2-symmetric 2,2'-bipyridyl ligand was prepared from 2-chloro-4-methyl-5H-[llpyrindine. This pyrindine was prepared from a common intermediate that was used in the synthesis of the first generation of ligands. The chirality of this second generation ligand was installed by a Sharpless asymmetric dihydroxylation reaction (90% ee). The subsequently elaborated 2,2'-bipyridyl ligand (enriched to>99% ee) was then evaluated in copper(1)-catalyzed asymmetric cyclopropanation reactions of alkenes and diazoesters. In the case of the reaction of para-fluorostyrene and tert-butyl diazoacetate, the corresponding cyclopropane was formed in good diastereoselectivity (92:8) and in excellent enantioselectivity (99% ee). This ligand was also evaluated in copper(I1)-catalyzed asymmetric Friedel-Crafts alkylation reactions of various substituted indoles (up to 90% ee) and in copper(1)- catalyzed asymmetric allylic oxidation reactions of cyclic alkenes with tert-butyl peroxybenzoate (up to 9 1 % ee).
Download or read book Enantioselection in Asymmetric Catalysis written by Ilya D. Gridnev and published by CRC Press. This book was released on 2016-11-03 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt: The field of asymmetric catalysis is currently one of the hottest areas in chemistry. This unique book focuses on the mechanism of enantioselectivity in asymmetric catalysis, rather than asymmetric catalysis from the synthetic view. It describes reliable, experimentally and computationally supported mechanisms, and discusses the danger of so-called "plausible" or "accepted" mechanisms leading to wrong conclusions. It draws parallels to enzymatic catalysis in biochemistry, and examines in detail the physico-chemical aspects of enantioselective catalysis.
Download or read book Olefin Polymerization written by Walter Kaminsky and published by Wiley-VCH. This book was released on 2006-08-18 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: With an enormous velocity, olefin polymerization has expanded to one of the most significant fields in polymers since the first industrial use about 50 years ago. In 2005, 100 million tons of polyolefins were produced - the biggest part was catalyzed by metallorganic compounds. The Hamburg Macromolecular Symposium 2005 with the title "Olefin Polymerization" involved topics such as new catalysts and cocatalysts, kinetics, mechanism and polymer reaction engineering, synthesis of special polymers, and characterization of polyolefins. The conference combined scientists from different disciplines to discuss latest research results of polymers and to offer each other the possibility of cooperation. This is reflected in this volume, which contains invited lectures and selected posters presented at the symposium.
Download or read book Synthesis of New Chiral Ligands and Their Application in Catalytic Enantioselective Reactions written by Kedar Shankar Karmarkar and published by . This book was released on 1996 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book New Approaches to and Mechanistic Studies of Homogeneous Asymmetric Catalysis written by Barbara M. Kimmich and published by . This book was released on 1997 with total page 654 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Synthesis and Application of Bulky S stereogenic and P Stereogenic Chiral Ligands written by Seán Doran and published by . This book was released on 2012 with total page 305 pages. Available in PDF, EPUB and Kindle. Book excerpt: This doctoral thesis was focused on the design and synthesis of novel chiral ligands for application in asymmetric catalysis. One of the best examples of asymmetric catalysis is the asymmetric hydrogenation reaction for its atom economy, ease of access to both S and R enantiomers and almost ultimate enantiomeric excess obtainable in a multitude of substrates. There has been much investigation into this reaction and there has been a plethora of chiral ligands designed which catalyze this reaction in high enantiomeric excess using metals such as rhodium, iridium and ruthenium. The vast majority of these ligands are diphosphines with their chirality lying either on the backbone of the ligand or on the coordinating phosphorus atom itself. In the beginning of this work investigation was undertook to explore the possibility of successfully employing a new type of ligand class in the asymmetric hydrogenation reaction, namely the N-phosphino sulfinamide or PNSO ligands. PNSO ligands had been successfully applied to the asymmetric Pauson-Khand reaction in the Riera group yielding cyclopentenone Pauson-Khand adducts in high yield and very high enantioselectivity. The family of PNSO ligands prepared in the Riera group was attractive because apart from the high yields and enantioselectivities obtained from the reactions in which they were used, they proved to be easily prepared in short syntheses from commercially available starting materials. It was believed if they could be successfully applied in asymmetric hydrogenation for their ease of preparation they would be an attractive alternative to the diphosphine ligand class. Unfortunately the first two PNSO-Rh complexes successfully prepared provided low enantioselectivities and difficulties were encountered while trying to prepare further analogues. After some time trying to achieve PNSO-Rh complex analogues unsuccessfully the direction of the project was shifted away from the N-phosphino sulfinamide ligand class in asymmetric hydrogenation. The MaxPhos ligand had recently been developed in the group and had proven highly promising. A study was demanded of its substrate scope as applied in rhodium catalyzed asymmetric hydrogenation. Substrates already described in the literature were prepared and the asymmetric hydrogenation of them catalyzed by the MaxPhos-Rh precatalyst was performed and conditions to do so were optimized. Of seven substrates prepared the MaxPhos-Rh proved to hydrogenate five of those with high enantioselectivity. The TOF of the MaxPhos rhodium catalyst applied in the hydrogenation of the Z-MAC substrate was examined by monitoring the flux of hydrogen and was calculated at 0.065 s-1. MaxPhos complexes of cobalt and palladium were prepared to form part of the investigation into widening the reaction scope of the ligand. [(MaxPhos)Co2(CO)4(C2H2)] proved to catalyze the Pauson-Khand reaction of norbornadiene and 1-hexyne with 24 % yield and 28 %, a noteworthy enantiomeric excess for the catalytic asymmetric Pauson-Khand reaction. Chalcogenated derivatives of MaxPhos were prepared. The diselenide was used to explore the electronic nature of the ligand. The MaxPhos-rhodium carbonyl stretching was examined. MaxPhos-BH3 was used to prepare mono-chalcogenated MaxPhos derivatives. They were applied also in asymmetric hydrogenation once complexed to rhodium but enantiomeric excess of no more than 21 % was obtained in the hydrogenation of the substrate Z-MAC. The aminophosphine, a chiral building block and key intermediate in the preparation of the MaxPhos ligand, was used in the attempt to prepare bulky chiral amidine ligands and although two such species were prepared they proved inapplicable in asymmetric catalysis.
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.
Download or read book Chiral Auxiliaries and Ligands in Asymmetric Synthesis written by J. Seyden-Penne and published by Wiley-Interscience. This book was released on 1995-10-23 with total page 744 pages. Available in PDF, EPUB and Kindle. Book excerpt: Table of Contents Preface Abbreviations Introduction 1 1 Enantiomerically Pure Chiral Auxiliaries 43 2 Chiral Reagents 87 3 Chiral Catalysis and Catalysts Bearing Chiral Ligands 117 4 Asymmetric Deprotonations and Protonations 143 5 Alkylations and Related Reactions 157 6 Additions to C=O and C=N Double Bonds 209 7 Additions to Carbon-Carbon Double Bonds 367 8 Additions to Double Bonds Bearing Heteroatoms. Oxidations of Sulfides and Selenides 503 9 Cycloadditions 513 10 Sigmatropic Rearrangements 593 11 Transition Metal Catalyzed Reactions 619 References 637 Index 707.
Download or read book Enantioselective Titanium catalysed Transformations written by Helene Pellissier and published by World Scientific. This book was released on 2016-01-15 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chiral titanium complexes are low-cost, low-toxicity and high-efficiency catalysts. Impressive progress on enantioselective titanium-catalysed transformations has been achieved in the past seven years, with exciting new discoveries ranging from basic reactions to novel methodologies. Despite this, the field has not been substantially reviewed since 2008.This book contains up to date research and covers all types of enantioselective transformations using chiral titanium catalysts. It illustrates the economic, health, and environmental benefits of chiral titanium catalysts, showing the types of highly enantioselective reactions that they are able to induce are unlimited.Work presented here is aimed at researchers in organic and catalytic chemistry, and has been carefully curated to encourage future research possibilities.
Download or read book Homogeneous Hydrogenation written by P.A. Chaloner and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 293 pages. Available in PDF, EPUB and Kindle. Book excerpt: Homogeneous hydrogenation is one of the most thoroughly studied fields of homogeneous catalysis. The results of these studies have proved to be most important for an understanding of the underlying principles of the activation of small molecules by transition metal complexes. During the past three decades homogeneous hydrogenation has found widespread application in organic chemistry, including the production of important pharmaceuticals, especially where a sophisticated degree of selectivity is required. This volume presents a general account of the main principles and applications of homogeneous hydrogenation by transition metal complexes. Special attention is devoted to the mechanisms by which these processes occur, and the role of the recently discovered complexes of molecular hydrogen is described. Sources of hydrogen, other than H2, are also considered (transfer hydrogenation). The latest achievements in highly stereoselective hydrogenations have made possible many new applications in organic synthesis. These applications are documented by giving details of the reduction of important unsaturated substrates (alkenes, alkynes, aldehydes and ketones, nitrocompounds, etc.). Hydrogenation in biphasic and phase transfer catalyzed systems is also described. Finally, a discussion of the biochemical routes of H2 activation highlights the similarities and differences in performing hydrogenation in both natural and synthetic systems. For researchers working in the fields of homogeneous catalysis, especially in areas such as pharmaceuticals, plastics and fine chemicals.
Download or read book Axially Chiral Compounds written by Bin Tan and published by John Wiley & Sons. This book was released on 2021-11-22 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt: Axially Chiral Compounds Explore this comprehensive and current volume summarizing the characteristics, synthesis, and applications of axial chirality Appearing widely in natural products, biologically active molecules, asymmetric chemistry, and material science, axially chiral motifs constitute the core backbones of the majority of chiral ligands and organocatalysts in asymmetric catalysis. In a new work of particular relevance to synthetic chemists, Axially Chiral Compounds: Asymmetric Synthesis and Applications delivers a clearly structured and authoritative volume covering the classification, characteristics, synthesis, and applications of axial chirality. A must read for every synthetic chemist practicing today, the book follows the development history, research status, and applications of axial chirality. An introductory chapter familiarizes the reader with foundational material before the distinguished authors describe the different classes and the synthesis of axial chiral compounds used in asymmetric synthesis. The book concludes with a focus on the applications of chiral ligands, chiral catalysts, and materials. Readers will also benefit from the inclusion of: A thorough introduction to asymmetric synthesis, including biaryls atropisomers, heterobiaryls atropisomers, and non-biaryls atropisomers Explorations of chiral allene, spiro skeletons, and natural products Practical discussions of asymmetric transformation, chiral ligands, and chiral catalysts An examination of miscellaneous applications of axially chiral compounds Perfect for organic chemists, chemists working with or on organometallics, catalytic chemists, and materials scientists, Axially Chiral Compounds: Asymmetric Synthesis and Applications will also earn a place in the libraries of natural products chemists who seek a one-stop reference for compounds exhibiting axial chirality.
