Enantioselective Rhodium-catalyzed [2+2+2] and [4+2+2] Cycloaddition Reactions of Alkenyl Heterocumulenes
Author: Robert Tzu Hsiang Yu
Publisher:
Published: 2009
Total Pages: 524
ISBN-13:
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Author: Robert Tzu Hsiang Yu
Publisher:
Published: 2009
Total Pages: 524
ISBN-13:
DOWNLOAD EBOOKAuthor: Jennifer Ann Love
Publisher:
Published: 2000
Total Pages: 624
ISBN-13:
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Publisher:
Published: 2018
Total Pages:
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DOWNLOAD EBOOKAuthor: Ken Tanaka
Publisher: John Wiley & Sons
Published: 2018-12-31
Total Pages: 254
ISBN-13: 3527811893
DOWNLOAD EBOOKAn essential reference to the highly effective reactions applied to modern organic synthesis Rhodium complexes are one of the most important transition metals for organic synthesis due to their ability to catalyze a variety of useful transformations. Rhodium Catalysis in Organic Synthesis explores the most recent progress and new developments in the field of catalytic cyclization reactions using rhodium(I) complexes and catalytic carbon-hydrogen bond activation reactions using rhodium(II) and rhodium(III) complexes. Edited by a noted expert in the field with contributions from a panel of leading international scientists, Rhodium Catalysis in Organic Synthesis presents the essential information in one comprehensive volume. Designed to be an accessible resource, the book is arranged by different reaction types. All the chapters provide insight into each transformation and include information on the history, selectivity, scope, mechanism, and application. In addition, the chapters offer a summary and outlook of each transformation. This important resource: -Offers a comprehensive review of how rhodium complexes catalyze a variety of highly useful reactions for organic synthesis (e.g. coupling reactions, CH-bond functionalization, hydroformylation, cyclization reactions and others) -Includes information on the most recent developments that contain a range of new, efficient, elegant, reliable and useful reactions -Presents a volume edited by one of the international leading scientists working in the field today -Contains the information that can be applied by researchers in academia and also professionals in pharmaceutical, agrochemical and fine chemical companies Written for academics and synthetic chemists working with organometallics, Rhodium Catalysis in Organic Synthesis contains the most recent information available on the developments and applications in the field of catalytic cyclization reactions using rhodium complexes.
Author: W. Richard Counts
Publisher:
Published: 2007
Total Pages: 309
ISBN-13: 9780549070566
DOWNLOAD EBOOKWhile the total synthesis was not completed the results presented prove that the [4+2+2] reaction is a feasible step in the synthesis of complicated cyclooctanoid containing natural products. The history of the transition metal-catalyzed [m+n] and [m+n+o] cycloaddition reactions toward the synthesis of medium-sized ring systems will be discussed and compared to the results observed in this study. The case for further development of the catalytic reaction will also be presented.
Author: P. Andrew Evans
Publisher: Wiley-VCH
Published: 2006-03-06
Total Pages: 496
ISBN-13: 352760409X
DOWNLOAD EBOOKRhodium has proven to be an extremely useful metal due to its ability to catalyze an array of synthetic transformations, with quite often-unique selectivity. Hydrogenation, C-H activation, allylic substitution, and numerous other reactions are catalyzed by this metal, which presumably accounts for the dramatic increase in the number of articles that have recently emerged on the topic. P. Andrew Evans, the editor of this much-needed book, has assembled an internationally renowned team to present the first comprehensive coverage of this important area. The book features contributions from leaders in the field of rhodium-catalyzed reactions, and thereby provides a detailed account of the most current developments, including: Rhodium-Catalyzed Asymmetric Hydrogenation (Zhang) Rhodium-Catalyzed Hydroborations and Related Reactions (Brown) Rhodium-Catalyzed Asymmetric Addition of Organometallic Reagents to Electron Deficient Olefins (Hayashi) Recent Advances in Rhodium(I)-Catalyzed Asymmetric Olefin Isomerization and Hydroacylation Reactions (Fu) Stereoselective Rhodium(I)-Catalyzed Hydroformylation and Silylformylation Reactions and Their Application to Organic Synthesis (Leighton) Carbon-Carbon Bond-Forming Reactions Starting from Rh-H or Rh-Si Species (Matsuda) Rhodium(I)-Catalyzed Cycloisomerization and Cyclotrimerization Reactions (Ojima) The Rhodium(I)-Catalyzed Alder-ene Reaction (Brummond) Rhodium-Catalyzed Nucleophilic Ring Cleaving Reactions of Allylic Ethers and Amines (Fagnou) Rhodium(I)-Catalyzed Allylic Substitution Reactions and their Applications to Target Directed Synthesis (Evans) Rhodium(I)-Catalyzed [2+2+1] and [4+1] Carbocyclization Reactions (Jeong) Rhodium(I)-Catalyzed [4+2] and [4+2+2] Carbocyclizations (Robinson) Rhodium(I)-Catalyzed [5+2], [6+2], and [5+2+1] Cycloadditions: New Reactions for Organic Synthesis (Wender) Rhodium(II)-Stabilized Carbenoids Containing both Donor and Acceptor Substituents (Davies) Chiral Dirhodium(II)Carboxamidates for Asymmetric Cyclopropanation and Carbon-Hydrogen Insertion Reactions (Doyle) Cyclopentane Construction by Rhodium(II)-Mediated Intramolecular C-H Insertion (Taber) Rhodium(II)-Catalyzed Oxidative Amination (DuBois) Rearrangement Processes of Oxonium and Ammonium Ylides Formed by Rhodium(II)-Catalyzed Carbene-Transfer (West) Rhodium(II)-Catalyzed 1,3-Dipolar Cycloaddition Reactions (Austin) "Modern Rhodium-Catalyzed Organic Reactions" is an essential reference text for researchers at all levels in the general area of organic chemistry. This book provides an invaluable overview of the most significant developments in this important area of research, and will no doubt be an essential text for researchers at academic institutions and professionals at pharmaceutical/agrochemical companies.
Author: Piet W.N.M. van Leeuwen
Publisher: Springer Science & Business Media
Published: 2006-04-11
Total Pages: 291
ISBN-13: 0306469472
DOWNLOAD EBOOKIn the last decade there have been numerous advances in the area of rhodium-catalyzed hydroformylation, such as highly selective catalysts of industrial importance, new insights into mechanisms of the reaction, very selective asymmetric catalysts, in situ characterization and application to organic synthesis. The views on hydroformylation which still prevail in the current textbooks have become obsolete in several respects. Therefore, it was felt timely to collect these advances in a book. The book contains a series of chapters discussing several rhodium systems arranged according to ligand type, including asymmetric ligands, a chapter on applications in organic chemistry, a chapter on modern processes and separations, and a chapter on catalyst preparation and laboratory techniques. This book concentrates on highlights, rather than a concise review mentioning all articles in just one line. The book aims at an audience of advanced students, experts in the field, and scientists from related fields. The didactic approach also makes it useful as a guide for an advanced course.
Author: Wangze Song
Publisher:
Published: 2016
Total Pages: 0
ISBN-13:
DOWNLOAD EBOOKTransition metal-catalyzed cycloaddition reaction is one of the most efficient ways to access ring systems and remains to be one of the most active areas in organic chemistry. The discovery of 3-acyloxy-1,4-enyne (ACE) and 3-hydroxy-1,4-enyne (HYE) as the five-carbon components has led to the development of various Rh-catalyzed [5+1] and [5+2] cycloadditions in our group. These novel methods offered efficient access to highly substituted six- and seven-membered carbocycles. I will present our progresses on the development, application and mechanistic studies of the following four [5+1] and [5+2] cycloadditions. 1) Using ACE bearing an electron-rich ester as the five-carbon component, a [5+1] cycloaddition was realized under mild conditions for the preparation of highly substituted phenols. 2) Based on our previous success on Rh-catalyzed intermolecular [5+2] cycloaddition of ACE and alkynes, a library of highly substituted tropones was successfully prepared by modifying the cycloheptatriene products derived from the [5+2] cycloaddition. 3) The scope of the Rh-catalyzed intramolecular [5+2] cycloaddition of ACE with alkenes was expanded and the Rh-catalyzed intramolecular [5+2] cycloaddition of ACE with allenes was developed for the synthesis of highly functionalized bicyclic 5-7 fused ring systems with multiple stereogenic centers. 4) Using HYE as the 5-carbon component, a [5+1] carbonylative benzannulation reaction was previously developed in our group for the synthesis of tricyclic carbazoles. The scope of this tandem reaction is now expanded to the synthesis of tetra- and even pentacyclic ring systems including furocarbazoles, thiophenocarbazole, pyrrolocarbazole, and indolocarbazole. Metal carbene intermediates are involved in most of these cycloadditions. The strategy of using propargylic esters and propargylic alcohols as the Rh(I) carbene precursor should have broad implications in transition metal catalysis and metal carbene chemistry.
Author: Henri Ulrich
Publisher: Elsevier
Published: 2012-12-02
Total Pages: 375
ISBN-13: 0323162762
DOWNLOAD EBOOKCycloaddition Reactions of Heterocumulenes reviews cycloaddition reactions, particularly on hetercocumulenes having "four-electron" bonds. This book discusses the chemical relationship among the various classes of heterocumulenes, including their chemical reactivity which ranges from highly reactive species to nearly inert compounds. This text also investigates the nucleophilic reactions of ketenes and isocyanates with suitable substrates, and if possible, correlates available data with the reactivity of these species in cycloaddition reactions. This book also investigates the cycloaddition reactions of carbon suboxide and other aspects of its chemistry due to the presence of many other interrelated reactions. The synthetic organic chemist should also investigate the application of isocyanate reactions associated with the cumulative double bonds. This text investigates carbodiimides as useful reagents for peptide synthesis, and notes that the stability of carbodiimides increases significantly with sterical hindrance around the cumulative double bond system. This book discusses three compounds that have a central electrophilic carbon atom, namely, carbon dioxide, carbonyl sulfide, and carbon disulfide. The book also describes the cycloaddition reactions of sulfenes, of N-sulfinylamines, of N-sulfinylsulfonamides, and of sulfurdiimides. This book can prove useful for researchers, technicians, and scientists whose works involve organic chemistry, analytical chemistry, and other related fields of chemistry.
Author: Andy Wei Jen Yen
Publisher:
Published: 2020
Total Pages: 0
ISBN-13:
DOWNLOAD EBOOKThe synthesis of heterocycles using transition metal catalysis is a topic of broad interest in the field of organic chemistry. Transition metal catalysts allow many diverse bond disconnections to be realized, allowing for many ways to assemble heterocycles. Many of the transformations developed in the Lautens group are aimed at atom economical bond construction processes that streamline synthesis and minimize waste. The arylcyanation reaction and the asymmetric ring opening (ARO) reaction are two examples of methods developed in our group that embody this design principle. Chapter 1 of this thesis describes the development of a nickel-catalyzed arylcyanation reaction for the synthesis of 3,3-disubstituted oxindoles. This method was inspired by our work on the palladium-catalyzed arylcyanation reaction, originally developed to address challenges in the formal synthesis of (+)-corynoline. This nickel-catalyzed reaction uses an air-stable catalyst precursor to achieve a highly practical synthesis of a nitrile-containing oxindole via a domino Heck-cyanide capture cascade. Derivatizations of the nitrile group affords a series of novel heterocyclic scaffolds. Chapter 2 details the discovery and development of a novel enantioselective cycloisomerization reaction of oxabicyclic alkenes. Our work on developing the intramolecular asymmetric ring opening reaction led to the discovery of a novel epoxide synthesis. Specifically, when bridgehead substituted oxabicyclic alkenes with non-nucleophilic side chains are reacted with the [Rh(cod)2]OTf/PPF-PtBu2 catalyst in the absence of an external nucleophile, chiral epoxides are obtained. The synthesis of epoxides through cycloisomerization reactions possesses 100% atom economy and avoids the use of external oxidant. Chapter 3 describes an asymmetric ring opening reaction, specifically to address gaps in the methodology concerning amine nucleophiles. We were inspired by our group's previous attempts to use amino acid derived nucleophiles in the ARO reaction. We developed a way to incorporate amino acids into the ARO reaction by employing their 2-nitrobenzenesulfonamide (nosyl) derivatives as pronucleophiles. Intriguingly, we observed a divergence in reactivity between the diastereomeric hydroxyester products, in that one diastereomer was capable of lactonization and the other was not. This led to the enantioselective synthesis of chiral oxazinones, which are similar to the naphthoxazine class of compounds which possess dopaminergic activity.