Principles of Asymmetric Synthesis

Principles of Asymmetric Synthesis PDF Author: R.E. Gawley
Publisher: Elsevier
ISBN: 0080514774
Category : Science
Languages : en
Pages : 395

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Book Description
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.

Principles of Asymmetric Synthesis

Principles of Asymmetric Synthesis PDF Author: R.E. Gawley
Publisher: Elsevier
ISBN: 0080514774
Category : Science
Languages : en
Pages : 395

Get Book Here

Book Description
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.

Principles and Applications of Asymmetric Synthesis

Principles and Applications of Asymmetric Synthesis PDF Author: Guo-Qiang Lin
Publisher: John Wiley & Sons
ISBN: 0471465240
Category : Science
Languages : en
Pages : 536

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Book Description
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.

Asymmetric Synthesis

Asymmetric Synthesis PDF Author: Garry Procter
Publisher: Oxford University Press on Demand
ISBN: 9780198557258
Category : Science
Languages : en
Pages : 237

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Book Description
This book covers a wide range of reactions which are of importance in the asymmetric synthesis of organic compounds. The principles of asymmetric additions to carbonyls, enolate alkylation, aldol reactions, additions to C-C double bonds, reduction and oxidation, rearrangements, and hydrolysis/ esterification reactions are covered, and selected examples used to illustrated the various topics. Numerous references to original literature should be of ues to organic chemists interested in the area of asymmetric synthesis.

Principles of Asymmetric Synthesis

Principles of Asymmetric Synthesis PDF Author: Robert E. Gawley
Publisher: Elsevier
ISBN: 0080448607
Category : Science
Languages : en
Pages : 569

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Book Description
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. The aim of this book is to present a detailed analysis of the factors that govern stereoselectivity in organic reactions.

Asymmetric Synthesis of Nitrogen Heterocycles

Asymmetric Synthesis of Nitrogen Heterocycles PDF Author: Jacques Royer
Publisher: John Wiley & Sons
ISBN: 3527625518
Category : Science
Languages : en
Pages : 425

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Book Description
Here, all aspects of the topic are presented in a compact manner. The book is clearly structured, and divided into two sections -- asymmetric synthesis of heterocycles containing only one nitrogen and that of those with more than one nitrogen as a heteroatom -- such that the necessary information may be found at a glance. The international team of authors provides important experimental procedures, including industrial applications. Essential for synthetic chemists in pharmaceutical and agrochemical chemistry.

Asymmetric Synthesis II

Asymmetric Synthesis II PDF Author: Mathias Christmann
Publisher: John Wiley & Sons
ISBN: 3527652256
Category : Science
Languages : en
Pages : 406

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Book Description
After the overwhelming success of Asymmetric Synthesis - The Essentials, displaying a broad range of organic asymmetric syntheses, this is the second edition with latest subjects and authors. While the aim of the first edition was mainly to honor the achievements of the pioneers in asymmetric syntheses, the aim of this new edition was bringing the current developments, especially from younger colleagues, to the attention of students. The format of the book remained unchanged, i.e. short conceptual overviews by young leaders in their field including a short biography of the authors. The growing multidisciplinary research within chemistry is reflected in the selection of topics including metal catalysis, organocatalysis, physical organic chemistry, analytical chemistry, and its applications in total synthesis, materials research and industry. The prospective reader of this book is a graduate or undergraduate student of advanced organic chemistry as well as the industrial chemist who wants to get a brief update on the current developments in the field.

Organic Chemistry from Retrosynthesis to Asymmetric Synthesis

Organic Chemistry from Retrosynthesis to Asymmetric Synthesis PDF Author: Vitomir Šunjić
Publisher: Springer
ISBN: 3319299263
Category : Science
Languages : en
Pages : 221

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Book Description
This book connects a retrosynthetic or disconnection approach with synthetic methods in the preparation of target molecules from simple, achiral ones to complex, chiral structures in the optically pure form. Retrosynthetic considerations and asymmetric syntheses are presented as closely related topics, often in the same chapter, underlining the importance of retrosynthetic consideration of target molecules neglecting stereochemistry and equipping readers to overcome the difficulties they may encounter in the planning and experimental implementation of asymmetric syntheses. This approach prepares students in advanced organic chemistry courses, and in particular young scientists working at academic and industrial laboratories, for independently solving synthetic problems and creating proposals for the synthesis of complex structures.

Asymmetric Synthesis with Chemical and Biological Methods

Asymmetric Synthesis with Chemical and Biological Methods PDF Author: Dieter Enders
Publisher: John Wiley & Sons
ISBN: 3527610634
Category : Science
Languages : en
Pages : 470

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Book Description
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 Synthesis

Asymmetric Synthesis PDF Author: Gary M. Coppola
Publisher: Wiley-Interscience
ISBN:
Category : Science
Languages : en
Pages : 424

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Book Description
Presents in a logical, readable manner the synthetic utility of amino acids for the generation of chiral agents, intermediates, and final products by means of asymmetric synthesis. In the past 20 years asymmetric synthesis has forged to the forefront of organic chemistry. This book provides extensive schemes and reactions containing over 1900 structures to illustrate the varied assortment of chiral intermediates that can be generated from amino acids and their derivatives. Focuses on the alpha[l.c. Greek letter]-amino acids and second-generation intermediates that can be derived therefrom which are of general interest to organic chemists, in either the industrial or the academic environment. Special attention has been paid to the asymmetric synthesis of key pharmaceutical agents, agrochemicals, and a host of natural products including alkoloids, terpenoids, carbohydrates, and insect pheromones. Includes extensive and up-to-date references.

Catalytic Methods in Asymmetric Synthesis

Catalytic Methods in Asymmetric Synthesis PDF Author: Michelangelo Gruttadauria
Publisher: John Wiley & Sons
ISBN: 1118087984
Category : Science
Languages : en
Pages : 721

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Book Description
This book covers advances in the methods of catalytic asymmetric synthesis and their applications. Coverage moves from new materials and technologies to homogeneous metal-free catalysts and homogeneous metal catalysts. The applications of several methodologies for the synthesis of biologically active molecules are discussed. Part I addresses recent advances in new materials and technologies such as supported catalysts, supports, self-supported catalysts, chiral ionic liquids, supercritical fluids, flow reactors and microwaves related to asymmetric catalysis. Part II covers advances and milestones in organocatalytic, enzymatic and metal-based mediated asymmetric synthesis, including applications for the synthesis of biologically active molecules. Written by leading international experts, this book consists of 16 chapters with 2000 References and illustrations of 560 schemes and figures.