Download or read book New Concepts and Applications in Chiral Br nsted Acid and Base Catalysis written by Chang Min and published by . This book was released on 2017 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chiral Brønsted acidic small molecules have found widespread applications as organocatalysts from the beginning of this century. Weaker Brønsted acids such as diols and (thio)ureas, typically classified as hydrogen bonding catalysts, and stronger phosphoric acids have proven to be highly effective in a wide range of asymmetric transformations. Chiral carboxylic acids, much less developed than those mentioned above, have recently drawn the attention of organic chemists as complementary Brønsted acid catalysts. Given that the pKa of a chiral carboxylic acid is expected to lie between that of most hydrogen bond donor and chiral phosphoric acid catalysts, it provides new potential to activate a different set of substrates requiring appropriate catalyst acidity. More importantly, by taking advantage of the judicious design of the catalyst structure, the acidity can be largely increased by the stabilization of the corresponding counterion via all kinds of interactions. This dissertation outlines the development of a new type of conjugate-base-stabilized carboxylic acid to solve the problems that have not been addressed by previously existing catalytic systems. In addition, the development of innovative synthetic applications of known chiral phosphoric acids is also detailed. Specific projects include the inter-, intramolecular Povarov reactions of secondary amines, kinetic resolution of indolines, the synthesis of polycyclic amines via an oxidative Povarov approach, the biomimetic enantioselective synthesis of isoindolinones and a dual-catalysis approach to the kinetic resolution of 1,2-diaryl-1,2-diaminoethanes.
Download or read book New Frontiers in Asymmetric Catalysis written by Koichi Mikami and published by John Wiley & Sons. This book was released on 2007-05-04 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: A compilation of recent advances and applications in asymmetric catalysis The field of asymmetric catalysis has grown rapidly and plays a key role in drug discovery and pharmaceuticals. New Frontiers in Asymmetric Catalysis gives readers a fundamental understanding of the concepts and applications of asymmetric catalysis reactions and discusses the latest developments and findings. With contributions from preeminent scientists in their respective fields, it covers: * "Rational" ligand design, which is critically dependent on the reaction type (reduction, oxidation, and C-C bond formation) * Recent findings on activation of C-H bonds, C-C bonds, and small molecules (C=O, HCN, RN=C, and CO2) and the latest developments on C-C bond reorganization, such as metathesis * Advances in "chirally economical" non-linear phenomena, racemic catalysis, and autocatalysis * Some of the recent discoveries that have led to a renaissance in the field of organocatalysis, including the development of chiral Brönstead acids and Lewis acidic metals bearing the conjugate base of the Brönstead acids as the ligands and the chiral bi-functional acid/base catalysts The book ends with a thought-provoking perspective on the future of asymmetric catalysis that addresses both the challenges and the unlimited potential in this burgeoning field. This is an authoritative, up-to-date reference for organic chemists in academia, government, and industries, including pharmaceuticals, biotech, fine chemicals, polymers, and agriculture. It is also an excellent textbook for graduate students studying advanced organic chemistry or chemical synthesis.
Download or read book Asymmetric Bronsted Acid Catalysis written by Magnus Rueping and published by John Wiley & Sons. This book was released on 2016-02-23 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: A much-needed overview of the synthesis of chiral Brønsted acids and their applications in various organic transformations. The internationally recognized and highly respected expert authors summarize the most significant advances in this new and dynamically progressing field, with a special emphasis on BINOL-derived phosphoric acids. They also describe other catalysts, such as C-H, TADDOL-derived Brønsted, and sulfonic acids. For easy navigation, the chapters are organized in the first instance according to reactive intermediate and then sub-divided by reaction type. An appendix with selected experimental details for benign and straight-forward procedures rounds of the book, making this the number-one information source for organic chemists in academia and industry.
Download or read book Acido basic Catalysis written by Christian Marcilly and published by Editions Technips. This book was released on 2005-11 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a complete overview of acido-basic catalysis applied to refining and petrochemistry, as well as the fundamentals and the information required for a rational and coherent description of the major operations carried out in these two industries.The book places special emphasis on the reactional and mechanistic characteristics of hydrocarbon conversions and on the properties of the acids or bases underlying catalytic performance. It also focuses on the industrial aspects, showing how these characteristics and properties determine the choice and features of the processes used.This reference manual is intended for professionals, scientists, engineers and teachers wanting to acquire a solid background, develop their knowledge or find further information. It will also be useful to students specialising in catalysis and the catalytic conversions of hydrocarbons.Contents: Volume 1. 1. Overview on Acido-Basicity. 2. Main Acids, Superacids and Bases of Interest in Catalysis. 3. Chemistry of Carbocations. 4. Reactivity and Conversion Modes of the Main Hydrocarbon Families. 5. Introduction to Refining and Petrochemistry. 6. Base Catalysis. Examples of Industrial Applications. Glossary. Index. Volume 2. 7. Conversion of Aliphatic Feedstocks. 8. Conversion of Simple Aromatic Feedstocks. 9. Reactions between Various Hydrocarbons and the Alcohols. Conversion of Methanol into Hydrocarbons. 10. Catalytic Reforming. 11. Processes Used in the Conversion of Heavy Feedstocks. 12. Catalytic Dewaxing. 13. Shape Selectivity in Acid Catalysis. Conclusion. Glossary. Index.
Download or read book A New World in the Making written by Danilo Dolci and published by Praeger. This book was released on 1976-02-18 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book New Cascade Reactions in Chiral Bronsted Acid Catalysis written by Chien-Chi Hsiao and published by . This book was released on 2015 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cooperative Catalysis written by René Peters and published by John Wiley & Sons. This book was released on 2015-04-27 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by experts in the field, this is a much-needed overview of the rapidly emerging field of cooperative catalysis. The authors focus on the design and development of novel high-performance catalysts for applications in organic synthesis (particularly asymmetric synthesis), covering a broad range of topics, from the latest progress in Lewis acid / Br?nsted base catalysis to e.g. metal-assisted organo catalysis, cooperative metal/enzyme catalysis, and cooperative catalysis in polymerization reactions and on solid surfaces. The chapters are classified according to the type of cooperating activating groups, and describe in detail the different strategies of cooperative activation, highlighting their respective advantages and pitfalls. As a result, readers will learn about the different concepts of cooperative catalysis, their corresponding modes of operation and their applications, thus helping to find a solution to a specific synthetic catalysis problem.
Download or read book Asymmetric Br nsted Acid Catalysis written by Magnus Rueping and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of Anion binding Approaches to Asymmetric Catalysis written by Nisha Mittal and published by . This book was released on 2014 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dual catalytic approach in asymmetric catalysis has gained considerable attention in recent times. Many otherwise inefficient and unattainable chemical processes can be accomplished by this approach. Outlined within this dissertation are recent efforts in improving the overall efficiency of this process as well as expanding this method involving nucleophilic/anion-binding catalysis to the kinetic resolution of allylic amines and 1,2-diamines. An efficient catalytic system has been identified through targeted structural modifications of both the achiral nucleophilic catalyst and the chiral anion-binding co-catalyst. This has resulted in increased selectivities while simultaneously allowing for significantly reduced catalyst loadings. Based on the mechanistic insight into the anion binding approach for the kinetic resolution of amines, we established that there was a 1:1 catalyst to benzoate anion binding ratio. Cooperative approaches in which Brønsted acids act in concert with other Brønsted acids or (thio) urea co-catalysts have gained significance. This study describes the synthesis of a new class of chiral conjugate-base-stabilized Brønsted acid catalysts and a new concept for cooperative hydrogen bonding/ Brønsted acid catalysis. These chiral Brønsted acids contain a carboxylic acid group which is connected via an appropriate linker to an anion receptor moiety such as a thiourea. Substrate protonation by the catalyst results in the association of the conjugate base with the anion recognition site, resulting in the formation of a rigid catalyst/substrate ion pair. We were able to successfully apply this concept to the catalytic enantioselective Povarov and Pictet-Spengler reactions.
Download or read book Borox Catalysis written by Anil Kumar Gupta and published by . This book was released on 2012 with total page 837 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Principles and Applications of Asymmetric Synthesis written by Guo-Qiang Lin and published by John Wiley & Sons. This book was released on 2003-05-29 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt: Asymmetric synthesis remains a challenge to practicing scientistsas the need for enantiomerically pure or enriched compoundscontinues to increase. Over the last decade, a large amount ofliterature has been published in this field. Principles andApplications of Asymmetric Synthesis consolidates and evaluates themost useful methodologies into a one-volume resource for theconvenience of practicing scientists and students. Authored by internationally renowned scientists in the field, thisreliable reference covers more than 450 reactions and includesimportant stoichiometric as well as catalytic asymmetric reactions.The first chapter reviews the basic principles, commonnomenclature, and analytical methods, and the remainder of the bookis organized according to reaction type. The text examines suchtopics as: Carbon-carbon bond formations involving carbonyls, enamines,imines, and enolates Asymmetric C-O bond formations including epoxidation,dihydroxylation, and aminohydroxylation Asymmetric synthesis using the Diels-Alder reaction and othercyclizations Applications to the total synthesis of natural products Use of enzymes in asymmetric synthesis Practicing chemists in the pharmaceutical, fine chemical, andagricultural professions as well as graduate students will findthat Principles and Applications of Asymmetric Synthesis affordscomprehensive and current coverage.
Download or read book Modern Reduction Methods written by Pher G. Andersson and published by John Wiley & Sons. This book was released on 2008-09-08 with total page 522 pages. Available in PDF, EPUB and Kindle. Book excerpt: With its comprehensive overview of modern reduction methods, this book features high quality contributions allowing readers to find reliable solutions quickly and easily. The monograph treats the reduction of carbonyles, alkenes, imines and alkynes, as well as reductive aminations and cross and heck couplings, before finishing off with sections on kinetic resolutions and hydrogenolysis. An indispensable lab companion for every chemist.
Download or read book Comprehensive Coordination Chemistry II written by J. A. McCleverty and published by Newnes. This book was released on 2003-12-03 with total page 11845 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive Coordination Chemistry II (CCC II) is the sequel to what has become a classic in the field, Comprehensive Coordination Chemistry, published in 1987. CCC II builds on the first and surveys new developments authoritatively in over 200 newly comissioned chapters, with an emphasis on current trends in biology, materials science and other areas of contemporary scientific interest.
Download or read book Enzymes written by Robert A. Copeland and published by John Wiley & Sons. This book was released on 2004-04-07 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fully updated and expanded-a solid foundation for understandingexperimental enzymology. This practical, up-to-date survey is designed for a broadspectrum of biological and chemical scientists who are beginning todelve into modern enzymology. Enzymes, Second Editionexplains the structural complexities of proteins and enzymes andthe mechanisms by which enzymes perform their catalytic functions.The book provides illustrative examples from the contemporaryliterature to guide the reader through concepts and data analysisprocedures. Clear, well-written descriptions simplify the complexmathematical treatment of enzyme kinetic data, and numerouscitations at the end of each chapter enable the reader to accessthe primary literature and more in-depth treatments of specifictopics. This Second Edition of Enzymes: A Practical Introductionto Structure, Mechanism, and Data Analysis features refinedand expanded coverage of many concepts, while retaining theintroductory nature of the book. Important new featuresinclude: A new chapter on protein-ligand binding equilibria Expanded coverage of chemical mechanisms in enzyme catalysisand experimental measurements of enzyme activity Updated and refined discussions of enzyme inhibitors andmultiple substrate reactions Coverage of current practical applications to the study ofenzymology Supplemented with appendices providing contact information forsuppliers of reagents and equipment for enzyme studies, as well asa survey of useful Internet sites and computer software forenzymatic data analysis, Enzymes, Second Edition isthe ultimate practical guide for scientists and students inbiochemical, pharmaceutical, biotechnical, medicinal, andagricultural/food-related research.
Download or read book The Role of Catalysis for the Sustainable Production of Bio fuels and Bio chemicals written by Kostas Triantafyllidis and published by Newnes. This book was released on 2013-03-19 with total page 607 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Role of Catalysis for the Sustainable Production of Bio-fuels and Bio-chemicals describes the importance of catalysis for the sustainable production of biofuels and biochemicals, focused primarily on the state-of-the-art catalysts and catalytic processes expected to play a decisive role in the "green" production of fuels and chemicals from biomass. In addition, the book includes general elements regarding the entire chain of biomass production, conversion, environment, economy, and life-cycle assessment. Very few books are available on catalysis in production schemes using biomass or its primary conversion products, such as bio-oil and lignin. This book fills that gap with detailed discussions of: Catalytic pyrolysis of lignocellulosic biomass Hybrid biogasoline by co-processing in FCC units Fischer-Tropsch synthesis to biofuels (biomass-to-liquid process) Steam reforming of bio-oils to hydrogen With energy prices rapidly rising, environmental concerns growing, and regulatory apparatus evolving, this book is a resource with tutorial, research, and technological value for chemists, chemical engineers, policymakers, and students. Includes catalytic reaction mechanism schemes and gives a clear understanding of catalytic processes Includes flow diagrams of bench-, pilot- and industrial-scale catalytic processing units and demonstrates the various process technologies involved, enabling easy selection of the best process Incorporates many tables, enabling easy comparison of data based on a critical review of the available literature
Download or read book Organocatalysis written by Manfred Reetz and published by Springer Science & Business Media. This book was released on 2008-05-27 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an excellent overview on state-of-the-art of modern organocatalysis. It presents the contributions from leading experts, with backgrounds in academia and industry, to an Ernst Schering Research Foundation Symposium held in April 2007. It will be of interest to those who want a general overview of the topic, but also to those who want to learn more about the state-of-the-art, current trends and perspectives in this highly dynamic field of research.
Download or read book Chiral Liquid Chromatography written by w Lough and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: While working as a chromatographer in the pharmaceutical industry, it became apparent to the editor that there was a pressing need for a comprehensive reference text for analysts working on the resolution of enantiomers by liquid chromatography (LC). This need arises from the fact that, whereas previously it was very difficult to determine enantiomers by direct means, there is now a wide choice of direct LC methods. At the same time, regulatory authorities have been changing their attitudes towards the administration of pharmaceuticals as racemates, partly because it is now possible to study the individual enantiomers. Clearly this abundance of new information needs to be rationalized. More importantly, the chiral LC systems which are commercially available or readily accessible to the practising chromatographer needed to be reviewed and, to a much greater extent than in existing reviews or books, discussed in terms of their practical application. Accordingly this book is very much orientated towards the practical aspects of these commercially available and readily accessible chiral LC systems. To this end, it is written for practising chromatographers by a team of practising, experienced chromatographers who have spent many years tackling the problems presented by resolving enantiomers by LC. The practical aspects of common chiral LC systems cannot be fully understood if discussed in isolation.
