This book provides the reader with an illustrative overview concerning successful and widely used applications of organocatalysis in the field of natural product synthesis. The main focus will be on organocatalytic key-steps for each (multi-step) synthesis described, whereas other often particularly innovative transformations will be omitted, as this would be beyond the scope of this volume.
Addressing a dynamic aspect of organic chemistry, this book describes synthetic strategies and applications for multicomponent reactions – including key routes for synthesizing complex molecules. • Illustrates the crucial role and the important utility of multicomponent reactions (MCRs) to organic syntheses • Compiles novel and efficient synthetic multicomponent procedures to give readers a complete picture of this class of organic reactions • Helps readers to design efficient and practical transformations using multicomponent reaction strategies • Describes reaction background, applications to synthesize complex molecules and drugs, and reaction mechanisms
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.
Edited by the leading expert on the topic, this is the first book to present the latest developments in this exciting field. Alongside the theoretical aspects, the top contributors provide practical protocols to give readers additional important information otherwise unavailable. A must for every synthetic chemist in academia and industry.
Uniting the key organic topics of total synthesis and efficient synthetic methodologies, this book clearly overviews synthetic strategies and tactics applied in total synthesis, demonstrating how the total synthesis of natural products enables scientific and drug discovery. • Focuses on efficiency, a fundamental and important issue in natural products synthesis that makes natural product synthesis a powerful tool in biological and pharmaceutical science • Describes new methods like organocatalysis, multicomponent and cascade reactions, and biomimetic synthesis • Appeals to graduate students with two sections at the end of each chapter illustrating key reactions, strategies, tactics, and concepts; and good but unfinished total synthesis (synthesis of core structure) before the last section • Compiles examples of solid phase synthesis and continuing flow chemistry-based total synthesis which are very relevant and attractive to industry R&D professionals
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.
Sets forth an important group of environmentally friendly organic reactions With contributions from leading international experts in organic synthesis, this book presents all the most important methodologies for stereoselective organocatalysis, fully examining both the activation mode as well as the type of bond formed. Clear explanations guide researchers through all the most important methods used to form key chemical bonds, including carbon-carbon (C–C), carbon-nitrogen (C–N), and carbon-halogen (C–X) bonds. Moreover, readers will discover how the use of non-metallic catalysts facilitates a broad range of important reactions that are environmentally friendly and fully meet the standards of green chemistry. Stereoselective Organocatalysis begins with an historical overview and a review of activation modes in asymmetric organocatalysis. The next group of chapters is organized by bond type, making it easy to find bonds according to their applications. The first of these chapters takes a detailed look at the many routes to C–C bond formation. Next, the book covers: Organocatalytic C–N bond formation C–O bond formation C–X bond formation C–S, C–Se, and C–B bond formation Enantioselective organocatalytic reductions Cascade reactions forming both C–C bonds and C–heteroatom bonds The final chapter is devoted to the use of organocatalysis for the synthesis of natural products. All the chapters in the book are extensively referenced, serving as a gateway to the growing body of original research reports and reviews in the field. Based on the most recent findings and practices in organic synthesis, Stereoselective Organocatalysis equips synthetic chemists with a group of organocatalytic reactions that will help them design green reactions and overcome many challenges in organic synthesis.
Brings together the best tested and proven stereoselective synthetic methods Both the chemical and pharmaceutical industries are increasingly dependent on stereoselective synthetic methods and strategies for the generation of new chiral drugs and natural products that offer specific 3-D structures. With the publication of Stereoselective Synthesis of Drugs and Natural Products, researchers can turn to this comprehensive two-volume work to guide them through all the core methods for the synthesis of chiral drugs and natural products. Stereoselective Synthesis of Drugs and Natural Products features contributions from an international team of synthetic chemists and pharmaceutical and natural product researchers. These authors have reviewed the tremendous body of literature in the field in order to compile a set of reliable, tested, and proven methods alongside step-by-step guidance. This practical resource not only explores synthetic methodology, but also reaction mechanisms and applications in medicinal chemistry and drug discovery. The publication begins with an introductory chapter covering general principles and methodologies, nomenclature, and strategies of stereoselective synthesis. Next, it is divided into three parts: Part One: General Methods and Strategies Part Two: Stereoselective Synthesis by Bond Formation including C-C bond formation C-H bond formation C-O bond formation C-N bond formation Other C-heteroatom formation and other bond formation Part Three: Methods of Analysis and Chiral Separation References in every chapter serve as a gateway to the literature in the field. With this publication as their guide, chemists involved in the stereoselective synthesis of drugs and natural products now have a single, expertly edited source for all the methods they need.
In the last decade a new era in asymmetric catalysis has been realised by the discovery of L-proline induced chiral enamines from carbonyls. Inspired by this, researchers have developed many other primary catalytic species in situ, more recently secondary catalytic species such as aminals have been identified for use in asymmetric synthesis. High-yielding asymmetric synthesis of bioactive and natural products through mild catalysis is an efficient approach in reaction engineering. In the early days, synthetic chemists mainly focused on the synthesis of complex molecules, with less attention on the reaction efficiency and eco-friendly conditions. Recent investigations have been directed towards the development of atom economy, eco-friendly and enantioselective synthesis for more targeted and efficient synthesis. Building on the momentum of this rapidly expanding research area, Dienamine catalysis for organic synthesis will provide a comprehensive introduction, from the preformed species, in situ generation and onto their applications in the synthesis of bioactive molecules and natural products.
