Chiral Auxiliaries in Cycloadditions

Acetylene systems present a new route to cyclic compounds as an alternative to more traditional methods employed in classical organic chemistry. The synthesis of cyclic structures based on acetylene systems has important applications in the formation of nanostructures, naturally occurring compounds and chemosensory materials for the design of nonlinear optics, electronic and photonic devices. Alkynes in Cycloadditions presents a modern review of regioselective synthesis of aromatic and non-aromatic carbocyclic and heterocyclic ring systems based primarily on [2+2+2] and [4+2] cycloadditions, and other reactions of acetylenic units including enediynes and enyne-allenes. Topics covered include: New strategies for the formation of aromatic and polynuclear hydrocarbons based on (Z)-hex-3-en-1,5-diyne and (Z)-hepta-1,2,4-triene-6-yne blocks. One-step synthesis of benzene derivatives, β-substituted naphthalenes and acenes by the cycloaromatization of enediynes and enyne-allenes by Bergman, Myers-Saito and Shmittel. Mechanisms of cycloaromatization resulting in the formation of fulvene and indene systems. Heterocyclization involving enyne-carbodiimides. New achievements in classical cycloaddition reactions such as the Diels-Alder condensation with acetylenic dienophiles and [2+2] cycloadditions with acetylene components Alkynes in Cycloadditions presents a comprehensive summary of the literature on methods for the synthesis of ring systems from acetylenes for academic researchers working in the fields of organic synthesis, physical organic chemistry, organometallic chemistry, catalysis, materials science, nanomaterials and biochemistry.

A complete overview covering the application of metal-based chiral Lewis acids from all parts of the periodic table, the Author emphasizes the most recent contributions to the field as well as prominent direction of development. The book discusses the design of chiral complexes as well as a wide spectrum of reactions promoted by various chiral Lewis acids, including water-compatible acids as well as the most important applications in the chemical and pharmaceutical industries. A must-have for catalytic and organic chemists working in the field, both in academia and industry, as well as pharmaceutical and medicinal chemists.

An integrated view of chiral drugs—from concept and synthesisto pharmaceutical properties Chirality greatly influences a drug's biological and pharmacological properties. In an effort to achieve more predictable results from chiral drugs, the Food and Drug Administration now requires that these medicines be as pure as possible, which places great demands on drug synthesis, purification, analysis, and testing. To assist researchers in acquiring the essential knowledge to meet these rigid guidelines, Chiral Drugs focuses on three vital chiral technologies—asymmetric synthesis, biocatalytic process, and chiral resolution—to offer details on the basic concepts, key developments, and recent trends in chiral drug discovery, along with: The history of chiral drugs development and industrial applications of chiral technologies A section listing twenty-five approved or advanced-trial chiral drugs that lists each drug name, chemical name and properties, a representative synthetic pathway, pharmacological characterizations, and references An interdisciplinary approach combining synthetic organic chemistry, medicinal chemistry, and pharmacology Nearly two-thirds of the drugs on today's market are chiral drugs. Reducing and eliminating their negative characteristics is an ongoing and serious challenge for the pharmaceutical industry. With its well-balanced approach to covering each important aspect of chirality, Chiral Drugs champions important strategies for tipping the medical scale in a positive direction for the production of more effective—and safer—drugs.

Thorough and up-to-date, this book presents recent developments in this exciting research field. To begin with, the text covers the fabrication of chiral nanomaterials via various synthesis methods, including electron beam lithography, ion beam etching, chemical synthesis and biological DNA directed assembly. This is followed by the relevant theory and reaction mechanisms, with a discussion of the characterization of chiral nanomaterials according to the optical properties of metal nanoparticles, semiconductor nanocrystals, and nanoclusters. The whole is rounded off by a summary of applications in the field of catalysis, sensors, and biomedicine. With its comprehensive yet concise coverage of the whole spectrum of research, this is invaluable reading for senior researchers and entrants to the field of nanoscience and materials science.

This book reviews chiral polymer synthesis and its application to asymmetric catalysis. It features the design and use of polymer-immobilized catalysts and methods for their design and synthesis. Chapters cover peptide-catalyzed and enantioselective synthesis, optically-active polymers, and continuous flow processes. It collects recent advances in an important field of polymer and organic chemistry, with leading researchers explaining applications in academic and industry R & D.

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

Homogeneous asymmetric catalysis offers reliable results and the possibility to 'tune' the catalysis on a rational basis. A pitfall, however, is that the separation of the catalyst from the starting material and products is difficult and often results in the loss of the catalytic material. Immobilization offers a potential solution for the user of enantioselective catalysts in industrial processes and laboratories. Heterogeneous catalysis allows continuous operations, recycling of the catalyst, and an easy separation of the reaction products, reducing both waste and costs. Chemists in academia and industry will welcome this careful selection of topics in this handbook that provides readers with practical and detailed information about the technical requirements for the immobilization of chiral catalysts, their application in synthesis, and methods for recycling.

A comprehensive resource to the development and recent progress of zwitterion-oriented cycloadditions promoted by organoamines, organophosphines, N-heterocyclic carbenes Organocatalytic Cycloadditions for Synthesis of Carbo- and Heterocycles offers a clear explanationto thedevelopment of and the information on the latest research pertaining to zwitterion-oriented cycloadditions promoted by organoamines, organophosphines, N-heterocyclic carbenes. The authors—noted experts in the field—include a comprehensive review to the investigations of the reaction mechanisms and explore the synthesis of different products from the same starting materials. Filled with illustrative examples and designed to be accessible, the text shows how to control the chemo-, regio- and stereoselectivity and explains the further design of novel cycloaddition reactions catalyzed by organoamines and organophosphines based on zwitterion-oriented synthetic strategy. This important text: Explains why the formation of carbo- and heterocycles is a key transformation in organic synthesis. Offers a clear description to the development of zwitterion-oriented cycloadditions promoted by organoamines, organophosphines, N-heterocyclic carbenes, and explores the latest research Contains the most current examples involving synthetic transformations of organocatalytic cycloadducts Includes contributions from noted experts in the field of organic synthesis Written for organic chemists, pharmaceutical chemists, chemists in industry, graduates, and librarians, Organocatalytic Cycloadditions for Synthesis of Carbo- and Heterocyclesis is the essential guide to the topic.

An updated guide to the most current information available for determining how to use NMR spectroscopy to differentiate chiral compounds Differentiation of Chiral Compounds Using NMR Spectroscopy offers a thoroughly revised second edition to the essential volume that puts the focus on the chiral systems that are commercially available and have been widely vetted for use in NMR spectroscopy. The text covers a broad range of reagents that make it possible to determine the enantiomeric purity and assign the absolute configuration of many classes of compounds. Comprehensive in scope, the text describes the chiral NMR differentiating agents as derivatizing agents, solvating agents, metal-based reagents and liquid crystals and gels, and explains the range and types of compounds for which they can be used for analysis. New to this edition are the most recent findings in the field as well as the development of advanced NMR measurement techniques that allow for the simplification of complex spectra resulting in more readily identified enantiodifferentiation. This important resource: Includes the most recent coverage of a large range of compounds that can be analyzed using chiral NMR reagents Explores the use of chiral NMR reagents and explains their relationship to the stereochemistry of the analyzed molecules Offers the essential information needed to help decide which method is the best NMR method to apply to a class or molecules Contains experimental strategies for using the reagents that are likely to improve the quality of the results Differentiation of Chiral Compounds Using NMR Spectroscopy is a comprehensive guide designed for investigators planning to use NMR spectroscopy to determine enantiomeric purity or assign the absolute configuration of a compound.