Principles And Applications Of Asymmetric Synthesis

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.

The world is chiral. Most of the molecules in it are chiral, and asymmetric synthesis is an important means by which enantiopure chiral molecules may be obtained for study and sale. Using examples from the literature of asymmetric synthesis (more than 1300 references), the aim of this book is to present a detailed analysis of the factors that govern stereoselectivity in organic reactions. It is important to note that the references were each individually checked by the authors to verify relevance to the topics under discussion. The study of stereoselectivity has evolved from issues of diastereoselectivity, through auxiliary-based methods for the synthesis of enantiomerically pure compounds (diastereoselectivity followed by separation and auxiliary cleavage), to asymmetric catalysis. In the latter instance, enantiomers (not diastereomers) are the products, and highly selective reactions and modern purification techniques allow preparation - in a single step - of chiral substances in 99% ee for many reaction types. After an explanation of the basic physical-organic principles of stereoselectivity, the authors provide a detailed, annotated glossary of stereochemical terms. A chapter on "Analytical Methods" provides a critical overview of the most common methods for analysis of stereoisomers. The authors then follow the 'tried-and-true' format of grouping the material by reaction type. Thus, there are four chapters on carbon-carbon bond forming reactions (enolate alkylations, organometal additions to carbonyls, aldol and Michael reactions, and cycloadditions and rearrangements), one chapter on reductions and hydroborations (carbon-hydrogen bond forming reactions), and one on oxidations (carbon-oxygen and carbon-nitrogen bond forming reactions). Leading references are provided to natural product synthesis that have been accomplished using a given reaction as a key step. In addition to tables of examples that show high selectivity, a transition state analysis is presented to explain - to the current level of understanding - the stereoselectivity of each reaction. In one case (Cram's rule) the evolution of the current theory is detailed from its first tentative (1952) postulate to the current Felkin-Anh-Heathcock formalism. For other reactions, only the currently accepted rationale is presented. Examination of these rationales also exposes the weaknesses of current theories, in that they cannot always explain the experimental observations. These shortcomings provide a challenge for future mechanistic investigations.

The world is chiral. Most of the molecules in it are chiral, and asymmetric synthesis is an important means by which enantiopure chiral molecules may be obtained for study and sale. Using examples from the literature of asymmetric synthesis, this book presents a detailed analysis of the factors that govern stereoselectivity in organic reactions. After an explanation of the basic physical-organic principles governing stereoselective reactions, the authors provide a detailed, annotated glossary of stereochemical terms. A chapter on "Practical Aspects of Asymmetric Synthesis" provides a critical overview of the most common methods for the preparation of enantiomerically pure compounds, techniques for analysis of stereoisomers using chromatographic, spectroscopic, and chiroptical methods. The authors then present an overview of the most important methods in contemporary asymmetric synthesis organized by reaction type. Thus, there are four chapters on carbon-carbon bond forming reactions, one chapter on reductions, and one on oxidations (carbon-oxygen and carbon-nitrogen bond forming reactions). This organization allows the reader to compare the leading methods for asymmetric synthesis in an appropriate context. A highlight of the book is the presentation and discussion of transition states at the current level of understanding, for important reaction types. In addition, extensive tables of examples are used to give the reader an appreciation for the scope of each reaction. Finally, leading references are provided to natural product synthesis that has been accomplished using a given reaction as a key step. Authoritative glossary to aid understanding of stereochemical terminology Explanations of the key factors influencing stereoselectivity with numerous examples, organized by reaction type A handy reference guide to the literature of asymmetric synthesis for practitioners in the field

Asymmetric Synthesis of Natural Products Fully updated learning resource covering the concept of using natural product chemistry for strategies in asymmetric synthesis The third edition of Asymmetric Synthesis of Natural Products introduces students to the rapidly growing field of natural products in organic chemistry, discussing the practical, mainly pharmacological, importance of selected compounds and emphasizing the target-oriented approach of organic synthesis which is key in industrial strategies. To aid in reader comprehension, the text includes key references and an Index of Compounds. The textbook is based on two lecture courses (Asymmetric Synthesis & Asymmetric Synthesis of Natural Products), which the author has delivered more than 50 times over the past 20 years in Finland, the UK, Italy, and Greece. This third edition is fully updated from the earlier versions (published by Wiley in 1993 and 2012). The importance of natural products as truly renewable raw materials in sustainable chemistry and circular economy is illustrated through applications of e.g. organocatalysis, organometallic catalysis, and biocatalysis. The contents consist of traditional text supplemented with illustrations (such as chemical drawings and structural formulae). Three dimensional aspects are also discussed with the use of 3D renderings of structures for both reaction mechanisms (molecular modeling) and crystallographic data. Sample topics covered in the textbook include: The foundations of asymmetric synthesis, including the theory and applications of individual asymmetric reactions Sustainable development, the circular economy, and use of renewable raw materials that have become prominent in many fields of science and technology Various natural product classes, including carbohydrates, amino acids, peptides, proteins, nucleosides, nucleotides, nucleic acids, and polyketides The properties of these natural product classes, including their structures, biosynthesis, and interrelationships, as well as examples of asymmetric syntheses and the practical value of these compounds Asymmetric Synthesis of Natural Products is a comprehensive, authoritative, and up-to-date learning resource on the subject for advanced level undergraduate or early-stage graduate students. It is also useful for specialists already working in synthesis who wish to learn about asymmetric synthesis.

Deals with stereochemistry of specialised topics. This book provides a comprehensive account of concepts of Asymmetric Synthesis. It is based on three important principles: concepts and terminology used in asymmetric synthesis, the four types of asymmetric synthesis, and applications of asymmetric synthesis.

A comprehensive overview of fundamental concepts of asymmetric synthesis along with in-depth discussion. Recent developments that address important synthetic challenges are presented and highlighted with hundreds of examples.

Edited by two of the leading researchers in the field, this book provides a deep, interdisciplinary insight into stoichiometric and catalytic reactions in this continuously expanding area. A plethora of top German scientists with an international reputation covers various aspects, from classical organic chemistry to process development, and from the theoretical background to biological methods using enzymes. Throughout the focus is on the development of new synthetic methods in asymmetric synthesis, the synthesis of natural and bioactive compounds and the latest developments in both chemical and biological methods of catalysis, as well as the investigation of special technical and biotechnical aspects.

Asymmetric catalysis represents still one of the major challenges in modern organic chemistry. Besides the well-established asymmetric metal-complex-catalysed syntheses and biocatalysis, the use of "pure" organic catalysts turned out to be an additional efficient tool for the synthesis of chiral building blocks. In this handbook, the experienced authors from academia and industry provide the first overview of the important use of such metal-free organic catalysts in organic chemistry. With its comprehensive description of numerous reaction types, e.g., nucleophilic substitution and addition reactions as well as cycloadditions and redox reactions, this book targets organic chemists working in industry and academia, and deserves a place in every laboratory.