Download or read book P stereogenic Ligands in Enantioselective Catalysis written by Arnald Grabulosa and published by Royal Society of Chemistry. This book was released on 2011 with total page 521 pages. Available in PDF, EPUB and Kindle. Book excerpt: P-stereogenic ligands were among the first to be used in asymmetric catalysis but synthetic difficulties and prejudices have hampered their development. However, continuous screening for new chiral ligands means that they can no longer be ignored and this rigorous reference source reflects their renaissance.The book is filled with many examples from recent primary literature. The synthetic chemist will easily be able to follow the preparation methods which are accompanied by a description of the challenges and limitations. Those working in homogenous catalysis, and wanting to increase their repertoire of ligands, will be able to establish which have already been used in each reaction and their performance.This book provides comprehensive coverage of the application of P-stereogenic ligands in homogeneous catalysis. It begins with a brief chapter on generalities of P-stereogenic compounds: history, configurational stability, and interconversions among them.The book then goes on to describe the main preparative methods, from resolution of racemates to enantioselective catalysis, before focusing on the catalytic applications of P-stereogenic ligands. Chapter 7 describes the use of the ligands in catalytic hydrogenation and related reactions whereas chapter 8 deals with other reactions, mainly C-C bond forming reactions. The aim of these two final chapters is to give an outline of the usefulness of the ligands in homogeneous catalysis.
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 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 P Stereogenic Ligands with the Tert butylmethylphosphine Fragment Coordination Chemistry and Catalysis of Their Organometallic Complexes written by Albert Gallen Ortiz and published by . This book was released on 2019 with total page 429 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Thesis deals with the preparation, coordination chemistry and use in asymmetric homogeneous catalysis of several optically pure P-stereogenic ligands containing a tert-butylmethylphosphino fragment. In the first part a highly stereoselective synthesis of the Secondary Phosphine Oxide (SPO) tert-butylmethylphosphine oxide is presented. Despite its simplicity, the stereoselective synthesis of this SPO had not been described in the literature. It is known that SPOs present a tautomeric equilibrium between the air-stable pentavalent form (phosphine oxide) and the trivalent form (phosphinous acid), usually completely shifted towards the pentavalent form but that can be displaced towards the phosphinous acid form by metal complexation. In the Thesis the complexation of the mentioned oxide towards Ru, Rh, Ir, Ni, Pd and Au has been explored, yielding a variety of coordination and organometallic compounds, with several coordination modes of the ligand. Some asymmetric catalytic applications of these species have also been studied, giving good conversions but low enantioselectivities. In the second part of the Thesis, the C1-symmetric P-stereogenic ligand MaxPhos has been coordinated to [MCp*Cl] (M = Rh and Ir) and [Ru(p-cymene)Cl] fragments, yielding cationic M-stereogenic organometallic compounds as tetrafluoroborate or hexafluorophosphate salts. Interestingly, in all cases a single stereoisomer has been formed, as confirmed by NMR and X-ray crystallography. This has been rationalised by steric grounds. For Ir, the abstraction of the remaining chloride ligand by silver salts produced a diastereoselective C–H activation of a tert-butyl group of the ligand. The complexes have been used in transfer hydrogenation giving good activities but no enantioselectivities. Finally the third part of the Thesis is devoted to the cyclometallation of [Ir(MaxPHOX)COD]BArF complexes (MaxPHOX stands for a type of P,N phosphinooxazoline ligand recently described by our group having three stereogenic centres) by several ligands under hydrogen atmosphere. It has been found that cyclometallated Ir(III)-hydrido complexes are formed, which are very stable and have been characterised thoroughly. They have been used in asymmetric hydrogenation of N-alkylimines, giving in general complete conversions and very high enantioselectivities (up to 96% ee) for these substrates, which rank among the best described to date. The mechanism of the reaction has been studied and the stereochemical outcome rationalised by means of DFT-based computational methods.
Download or read book The Pauson Khand Reaction written by Ramon Rios Torres and published by John Wiley & Sons. This book was released on 2012-03-01 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Pauson-Khand reaction is an important reaction in the field of organic chemistry. It involves the transition-metal catalysed cycloaddition of an alkyne, an alkene and carbon monoxide, to produce cyclopentenones. The importance of this reaction originates from its high value in transforming simple components into the synthetically useful cyclopentenone unit, in which a high degree of molecular complexity can be achieved in a single step, with impressive stereochemical and regiochemical control. The Pauson-Khand Reaction investigates the nature and many variations of this reaction. Topics covered include: the mechanisms of Pauson‐Khand-type reactions non chiral intramolecular and intermolecular versions of Pauson‐Khand reactions asymmetric Pauson‐Khand reaction using chiral auxiliaries the enantioselective Pauson‐Khand reaction Pauson‐Khand reactions catalysed by metals other than cobalt unconventional Pauson‐Khand reactions the Pauson‐Khand reaction in total synthesis Presenting a comprehensive overview of this fundamental reaction, The Pauson-Khand Reaction will find a place on the bookshelves of any organic or organometallic chemist.
Download or read book P stereogenic Ligands in Rhodium and Ruthenium catalyzed Asymmetric Hydrogenation written by Francesca Anna Maienza and published by . This book was released on 2001 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 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.
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 Transition Metal catalyzed Methods for the Enantioselective Synthesis of P stereogenic Phosphines written by Vincent Sai Ho Chan and published by . This book was released on 2008 with total page 610 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Topics In Enantioselective Catalysis Recent Achievements And Future Challenges written by Angela Marinetti and published by World Scientific. This book was released on 2022-06-02 with total page 501 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book illustrates the broad field of enantioselective catalysis by highlighting a few topics, out of myriads, with the double aim to typify selected synthetic achievements and future challenges. Eleven research groups have highlighted topics of interest in either organo- or organometallic catalysis, related to their own expertise. For mature fields, these short chapters, far from being exhaustive, show updated overviews including major recent advances and disclose a few prospects. Other chapters focus on upcoming topics in enantioselective catalysis, i.e. on classes of reactions or families of catalysts that are expected to provide appealing synthetic tools when suitably mastered. For all these areas, recent studies demonstrate highly promising perspectives.
Download or read book Advances in Organometallic Chemistry written by and published by Elsevier. This book was released on 2024-05-24 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Organometallic Chemistry, Volume 81 in this ongoing series, highlights new advances in the field, with this new volume presenting interesting chapters written by an international board of authors. Specific chapters cover Recent Advances in the Catalytic Applications of NHC-Early Abundant Metals (Fe, Mn, Co) Complexes, A Guide to Non-Carbonyl, Non-Isocyano Organometallic Chemistry of Technetium-99 from Discovery to 2023, and Cyclopentadienyl, Amidinate (CPAM) Complexes of Groups 4 - 6 Transition Metals. Provides the latest information on cancer research Offers outstanding and original reviews on a range of cancer research topics Serves as an indispensable reference for researchers and students alike
Download or read book Comprehensive Asymmetric Catalysis written by Eric N. Jacobsen and published by Springer Science & Business Media. This book was released on 2003-09-22 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first supplement to the three volume reference work "Comprehensive Asymmetric Catalysis" critically reviews new developments to the hottest topics in the field written by recognised experts. Eleven chapters which are already in the major reference work have been supplemented and additionally five new chapters have been included. Thus the state-of-the art in this area is now re-established. Together with the basic three volume book set this supplement is not only the principal reference source for synthetic organic chemists, but also for all scientific researchers who use chiral compounds in their work (for example, in biochemical investigations and molecular medicine) as well as for pharmaceutical chemists and other industrial researchers who prepare chiral compounds.
Download or read book Comprehensive Inorganic Chemistry II written by and published by Newnes. This book was released on 2013-07-23 with total page 7694 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive Inorganic Chemistry II, Nine Volume Set reviews and examines topics of relevance to today’s inorganic chemists. Covering more interdisciplinary and high impact areas, Comprehensive Inorganic Chemistry II includes biological inorganic chemistry, solid state chemistry, materials chemistry, and nanoscience. The work is designed to follow on, with a different viewpoint and format, from our 1973 work, Comprehensive Inorganic Chemistry, edited by Bailar, Emeléus, Nyholm, and Trotman-Dickenson, which has received over 2,000 citations. The new work will also complement other recent Elsevier works in this area, Comprehensive Coordination Chemistry and Comprehensive Organometallic Chemistry, to form a trio of works covering the whole of modern inorganic chemistry. Chapters are designed to provide a valuable, long-standing scientific resource for both advanced students new to an area and researchers who need further background or answers to a particular problem on the elements, their compounds, or applications. Chapters are written by teams of leading experts, under the guidance of the Volume Editors and the Editors-in-Chief. The articles are written at a level that allows undergraduate students to understand the material, while providing active researchers with a ready reference resource for information in the field. The chapters will not provide basic data on the elements, which is available from many sources (and the original work), but instead concentrate on applications of the elements and their compounds. Provides a comprehensive review which serves to put many advances in perspective and allows the reader to make connections to related fields, such as: biological inorganic chemistry, materials chemistry, solid state chemistry and nanoscience Inorganic chemistry is rapidly developing, which brings about the need for a reference resource such as this that summarise recent developments and simultaneously provide background information Forms the new definitive source for researchers interested in elements and their applications; completely replacing the highly cited first edition, which published in 1973
Download or read book Asymmetric Organocatalysis Combined with Metal Catalysis written by Bruce A. Arndtsen and published by Springer Nature. This book was released on 2020-04-24 with total page 211 pages. Available in PDF, EPUB and Kindle. Book excerpt: The series Topics in Current Chemistry Collections presents critical reviews from the journal Topics in Current Chemistry organized in topical volumes. The scope of coverage is all areas of chemical science including the interfaces with related disciplines such as biology, medicine and materials science. The goal of each thematic volume is to give the non-specialist reader, whether in academia or industry, a comprehensive insight into an area where new research is emerging which is of interest to a larger scientific audience.Each review within the volume critically surveys one aspect of that topic and places it within the context of the volume as a whole. The most significant developments of the last 5 to 10 years are presented using selected examples to illustrate the principles discussed. The coverage is not intended to be an exhaustive summary of the field or include large quantities of data, but should rather be conceptual, concentrating on the methodological thinking that will allow the non-specialist reader to understand the information presented. Contributions also offer an outlook on potential future developments in the field.The chapter "Enamine/Transition Metal Combined Catalysis: Catalytic Transformations Involving Organometallic Electrophilic Intermediates" is available open access under a CC BY 4.0 License via link.springer.com.
Download or read book Asymmetric Catalysis written by B. Bosnich and published by Springer. This book was released on 2011-09-26 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: The rate of advance in areas of science is seldom constant. Usually certain fields effloresce with activity because of the ~ealization that solutions are possible to long standing important problems. So it is now with asymmetric catalysis, a field which promises to change profoundly the strategic thinking of synthetic chemists. As this Report will show, reagents which can induce catalytic enantiocontrol of chemical transformations could represent the ultimate synthetic method. Nearly all synthetic strategies of complex molecules involve steps which require enantiocontrol and, in many cases, a specific catalytic transformation embodying enan tiocontrol has enormous advantages in terms of the rate and economy of the reaction. Because asymmetric catalysis is in a formative stage, workers with different backgrounds have joined the field. This Workshop had representatives with organometallic, organic, structural, kinetic, enzymatic, microbiological and industrial backgrounds. Each had his own perspective and this Report represents a consensus of this group of eleven people. The result is probably as compre hensive and balanced a view of the subject as is possible at present. It is hoped that those who have until now had but a glancing interest in asymmetric catalysis will find this Report a useful indication of its present state. We believe that asymmetric catalysis will have an increasing impact on the development of chemistry and will eventually dominate much of synthetic and industrial chemistry.
Download or read book Asymmetric Synthesis in Organophosphorus Chemistry written by Oleg I. Kolodiazhnyi and published by John Wiley & Sons. This book was released on 2016-09-20 with total page 539 pages. Available in PDF, EPUB and Kindle. Book excerpt: Authored by one of the leading experts in the field, this is the only comprehensive overview of chiral organophosphorus compounds, from asymmetric synthesis to catalysis and pharmacological applications. As such, this unique reference covers the chemical background as well as spectroscopical analysis of phosphorus compounds, and thoroughly describes all the various synthetic strategies for these substances. Metal-, organo- and biocatalyzed reactions for the introduction of phosphorus are explained as are asymmetric oxidation and reduction methods for the preparation of all possible oxidation states of phosphorus. The text also includes industrial applications for these compounds. Of particular interest to chemists working in the field of asymmetric synthesis, as well as to the pharmaceutical industry due to the increasing number of phosphorous-containing drugs.
