Download or read book Studies of Rhodium catalyzed 5 2 Cycloadditions and Their Applications in Organic Synthesis written by Craig Owen Husfeld and published by . This book was released on 2001 with total page 744 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modern Rhodium Catalyzed Organic Reactions written by P. Andrew Evans and published by John Wiley & Sons. This book was released on 2006-03-06 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rhodium 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.

Download or read book Rhodium Catalysis in Organic Synthesis written by Ken Tanaka and published by John Wiley & Sons. This book was released on 2019-05-06 with total page 684 pages. Available in PDF, EPUB and Kindle. Book excerpt: An 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.

Download or read book Rhodium catalyzed 5 1 and 5 2 Cycloadditions Using 1 4 enyne as the Five carbon Component written by Wangze Song and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transition 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.

Download or read book Rhodium catalyzed Cycloadditions and Cycloisomerizations Involving Propargylic Esters and Alcohols written by Xiaoxun Li and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transition metal-catalyzed cyloaddition and cycloisomerization reactions occupy a central position within the realm of organic synthesis. Research described in this thesis focuses on using propargylic esters and alcohols as building blocks for rhodium(I)-catalyzed cycloadditions and cycloisomerizations. The discovery and application of combining the [pi]-acidity and redox/insertion reactivity of rhodium(I) complexes, led to the development of many new reactions. By taking advantage of Rh-catalyzed 1,3-acyloxy migration of propargylic esters, I developed two tandem reactions. One is Rh-catalyzed carbonylation of 3-acyloxy-1,4-enynes (ACEs) for the synthesis of highly substituted cyclopentenones, and the other is ring expansion of cyclopropanes or cyclobutanes for the preparation of highly functionalized seven-membered or eight-membered carbocycles. By taking advantage of Rh-catalyzed 1,2-acyloxy migration of propargylic esters adjacent to heterocycles, I developed a novel and practical method for the preparation of a series of heterocycles including indoles, benzofurans, carbazoles and benzothiophenes from substituted pyrroles, furans, indoles and thiophenes. Inspired by the first Rh-catalyzed intra- and intermolecular [5+2] cycloadditions of 3-acyloxy-1,4-enynes (ACEs) with alkynes, I developed a new five-carbon building block, an inverted ACE, for [5+2] cycloadditions by switching the position of the alkene and alkyne groups in ACE. By replacing the acyloxy group in ACE with OH leaving group and aniline nucleophile, a completely new type of 5-carbon building block (HYE) was designed for cycloadditions. The tandem indole annulation and [5+1] cycloaddition was realized for the synthesis of various highly substituted carbazoles. Natural products glycosinine and mahanimbine were prepared. Furthermore, indolyl Rh(I)-carbene could be generated from 3-hydroxy-1,4-enyne (HYE) through a dehydration process. With different N-protecting group, I prepared dimeric indoles, cyclopropyl indoles, vinyl indoles and other interesting indole derivatives.

Download or read book Rhodium Catalyzed Hydroformylation written by Piet W.N.M. van Leeuwen and published by Springer Science & Business Media. This book was released on 2006-04-11 with total page 291 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 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.

Download or read book Cycloaddition Reactions in Organic Synthesis written by Shu Kobayashi and published by John Wiley & Sons. This book was released on 2002 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the miners' strike in the 1980s, a worker is killed in the striking coalfields of Wales. Some months later, a government minister thought to be connected with the death is also shot. Lewis Redfern—once a radical but now a political analyst and journalist—pursues the sniper, a lonely hunt that leads him through an imbroglio of civil service leaks to a secret organization: a source of insurrection far more powerful than anyone could have suspected known as the Volunteers. In this fast-paced narrative of espionage and intrigue, Redfern, through his obsessive pursuit of justice, finally encounters the truth about himself as the novel discusses the conflict between moral choice and political loyalty.

Download or read book The Design and Development of a New Reaction Rhodium catalyzed 5 2 Cycloadditions written by Jennifer Ann Love and published by . This book was released on 2000 with total page 624 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Studies on Rhodium Catalyzed 5 2 Cocyclization Rections written by and published by Cuvillier Verlag. This book was released on 2004-09-20 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first part of this thesis dealt with the a new kind of precursors for transition metalcatalyzed cocyclization reactions containing a vinylbicyclopropyl unit, their synthesis and their behavior in cocyclization reactions. By introducing a second cyclopropane the catalyst might open this ring as well after insertion into the first cyclopropane ring. The ’basic’ formal [5+2] cycloaddition reaction would be extended to a [5+2+3] cocyclization reaction to form ten-membered rings. In addition to the importance as a new synthetic tool valuable insights into the mechanism of transition metal-catalyzed cocyclization reactions of vinylcyclopropanes are gained.

Download or read book Studies on Rhodium Catalyzed 5 2 Cocyclization Reactions written by Hermann Wegner and published by Cuvillier Verlag. This book was released on 2004 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Reactive Intermediates written by Leonardo S. Santos and published by John Wiley & Sons. This book was released on 2009-11-04 with total page 341 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the last two decades there has been considerable growth in the development of electrospray ionization mass spectrometry (ESI-MS) as a practical method in the study of reaction mechanisms. This method allows the interception and characterization of key intermediates, either as transient species or as protonated/deprotonated forms of neutral species by API-MS. The outstanding features and advantages of ESI-MS make it one of the most suitable tools for the fast screening of intermediates directly from solution, providing hitherto unavailable chemical information to organic chemists. This monograph provides an overview of the mechanisms involved in ESI-MS, the historical perspectives before looking further in-depth at specific reactions and intermediates. Written by researchers in the field, this book is an unique resource for the understanding of this cutting-edge technique.

Download or read book Alkynes in Cycloadditions written by Irina A. Maretina and published by John Wiley & Sons. This book was released on 2013-10-08 with total page 357 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Rhodium Catalyzed C H Bond Functionalization written by Andy Siu-Chun Tsai and published by . This book was released on 2011 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chapter 1. A sequence of research projects beginning with studies in diastereoselective C-H bond functionalization applied to the synthesis of ( - )-incarvaillateine to the Rh(III) catalyzed arylation of imines, are described. Some theory and mechanistic considerations are discussed in relation to the genesis of these projects. Research directions are summarized and rationalized. Chapter 2. The synthesis of ( - )-incarvillateine utilizing a key C-H bond alkylation step is described as a means to highlight the synthetic utility of a newly reported olefinic C-H bond functionalization methodology. Elements of diastereoselectivity are also explored in the key step which allows for the concise, stereoselective synthesis of the natural product. Progress in the area of enantioselective C-H alkylations are also summarized as it applies to the synthesis of other natural products. Chapter 3. A method for the enantioselective cyclization of N-allylimidazoles is developed. The reaction is thought to proceed via a novel, reactive N-heterocyclic carbene. High enantioselectivities are achieved, which is unusual in view of the elevated temperatures of the reaction. Chapter 4. The first general method for the oxidative coupling of unactivated alkenes via C-H bond functionalization is reported using a methyl oxime directing group. A silver abstractor is important to obtain reactivity. Several functional groups are compatible with the reaction and no precautions to exclude air are required. Chapter 5. A rare example of C-H activation and intermolecular coupling to N-protected-imines is achieved using a cationic Rh(III) catalyst. The reaction is directed by pyridines and related heterocycles and produces a variety of aryl-branched amines. The reaction accommodates several reactive functional groups and is mild enough to even couple with sensitive alkyl N-sulfonyl-imines.

Download or read book Investigations of 5 2 and Other Cycloadditions written by Lauren Elizabeth Sirois and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Those who study new reactions and their selectivities are often driven by an interest in developing novel, practical methods that can be exploited to achieve complex chemical transformations over a small number of synthetic steps. The ultimate goal of such efforts is to achieve step economy, an overarching principle of green chemistry that minimizes reagents, waste, and production time. The design and application of metal-catalyzed and light-mediated cycloadditions is one important avenue of research, as such transformations can be atom economical and, more importantly, can create multiple bonds, rings, and stereocenters in a single step toward targets of high complexity and value. Linked to the development of new reactions is the design and understanding of new catalysts and ligands possessing novel reactivities and selectivities. Step economy can also be achieved by the clever streamlining of multiple transformations into a single synthetic operation, thus further reducing material and personnel costs. Such single-flask serial/cascade reactions can be used for the rapid assembly of molecular scaffolds, some of which comprise the core of targets with exciting physical properties or biological activity. The research presented in this dissertation addresses all of these themes. Within the context of similar reactions of activated, strained rings, Chapter 1 introduces the metal-catalyzed [5+2] cycloaddition of vinylcyclopropanes (VCPs) and pi-systems for the construction of seven-membered rings, an important motif in many natural products and natural-product-inspired synthetic targets. Chapter 2 describes the latest advancements in new catalysts and new ligands for the strategically convergent and operationally simple rhodium(I)-catalyzed intermolecular [5+2] reactions of VCPs and alkyne feedstocks. In Chapter 3, the regioselectivity of intermolecular [5+2] cycloadditions is explored systematically, as unsymmetrical substrates can give rise to multiple regioisomeric cycloadducts depending upon the orientation of the alkyne during a postulated (turnover-limiting) migratory insertion mechanistic step. Chapters 4 and 5 illustrate the development and application of single-flask / serial reactions involving the [5+2] cycloaddition, making use of the catalysts and insights from Chapters 2 and 3. In Chapter 4, an intermolecular [5+2] cycloaddition of enynones and VCPs, followed by a Nazarov cyclization, is envisioned for strategically novel and rapid access to the bicyclo[5.3.0]decane skeleton from readily available components. Chapter 5 describes the evolution of a project that, guided by the principles of function-oriented synthesis to access the minimally necessary chemical space for function via the fewest synthetic steps, uses serial [5+2]/[4+2] cycloadditions to assemble novel, potent inhibitors of protein kinase C (PKC). Lastly, Chapter 6 describes a total synthesis of penifulvin A, a sesquiterpenoid metabolite reported as the first example of a naturally occurring dioxa[5,5,5,6]fenestrane. The synthetic strategy features the use of an arene-alkene meta photocycloaddition as the key complexity-generating reaction.

Download or read book Advances in Cycloaddition written by Michael Harmata and published by Elsevier. This book was released on 1999-03-18 with total page 185 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development and application of cycloaddition methodology continues to be at the forefront of research in synthetic organic chemistry. This volume begins with a review of methods available for the synthesis of seven-membered rings and is followed with work on metal-catalyzed cycloadditions. There is then an update on the cycloaddition chemistry of 2-pyrone, and then a unique application of photocycloaddition is detailed. The final chapter is a discussion of the latest explorations of the reaction of rhodium-stabilized vinyl carbenoids with dienes.

Download or read book C C Bond Activation written by Guangbin Dong and published by Springer. This book was released on 2014-09-18 with total page 265 pages. Available in PDF, EPUB and Kindle. Book excerpt: The series Topics in Current Chemistry presents critical reviews of the present and future trends in modern chemical research. The scope of coverage is all areas of chemical science including the interfaces with related disciplines such as biology, medicine and materials science. The goal of each thematic volume is to give the non-specialist reader, whether in academia or industry, a comprehensive insight into an area where new research is emerging which is of interest to a larger scientific audience. Each review within the volume critically surveys one aspect of that topic and places it within the context of the volume as a whole. The most significant developments of the last 5 to 10 years are presented using selected examples to illustrate the principles discussed. The coverage is not intended to be an exhaustive summary of the field or include large quantities of data, but should rather be conceptual, concentrating on the methodological thinking that will allow the non-specialist reader to understand the information presented. Contributions also offer an outlook on potential future developments in the field. Review articles for the individual volumes are invited by the volume editors. Readership: research chemists at universities or in industry, graduate students

Download or read book The Pauson Khand Reaction written by Ramon Rios Torres and published by John Wiley & Sons. This book was released on 2012-03-01 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Pauson-Khand reaction is an important reaction in the field of organic chemistry. It involves the transition-metal catalysed cycloaddition of an alkyne, an alkene and carbon monoxide, to produce cyclopentenones. The importance of this reaction originates from its high value in transforming simple components into the synthetically useful cyclopentenone unit, in which a high degree of molecular complexity can be achieved in a single step, with impressive stereochemical and regiochemical control. The Pauson-Khand Reaction investigates the nature and many variations of this reaction. Topics covered include: the mechanisms of Pauson‐Khand-type reactions non chiral intramolecular and intermolecular versions of Pauson‐Khand reactions asymmetric Pauson‐Khand reaction using chiral auxiliaries the enantioselective Pauson‐Khand reaction Pauson‐Khand reactions catalysed by metals other than cobalt unconventional Pauson‐Khand reactions the Pauson‐Khand reaction in total synthesis Presenting a comprehensive overview of this fundamental reaction, The Pauson-Khand Reaction will find a place on the bookshelves of any organic or organometallic chemist.