Download or read book Transition Metal Activation and Functionalization of Carbon hydrogen Bonds written by and published by . This book was released on 1992 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: We are investigating the fundamental thermodynamic and kinetic factors that influence carbon-hydrogen bond activation at homogeneous transition metal centers and the conversion of hydrocarbons into functionalized products of potential use to the chemical industry. Advances have been made in both understanding the interactions of hydrocarbons with metals and in the functionalization of hydrocarbons. We have found that RhCl(PR3)2(CNR) complexes can catalyze the insertion of isonitriles into the C-H bonds or arenes upon photolysis. The mechanism of these reactions was found to proceed by way of initial phosphine dissociation, followed by C-H activation and isonitrile insertion. We have also examined reactions of a series of arenes with (C5Me5)Rh(PMe3)PhH and begun to map out the kinetic and thermodynamic preferences for arene coordination. The effects of resonance, specifically the differences in the Hueckel energies of the bound vs free ligand, are now believed to fully control the C-H activation/?2-coordination equilibria. We have begun to examine the reactions of rhodium isonitrile pyrazolylborates for alkane and arene C-H bond activation. A new, labile, carbodiimide precursor has been developed for these studies. We have completed studies of the reactions of (C5Me5)Rh(PMe3)H2 with D2 and PMe3 that indicate that both?5 2!?3 ring slippage and metal to ring hydride migration occur more facilely than thermal reductive elimination of H2. We have examined the reactions of heterocycles with (C5Me5)Rh(PMe3)PhH and found that pyrrole and furan undergo C-H or N-H activation. Thiophene, however, undergoes C-S bond oxidative addition, and the mechanism of activation has been shown to proceed through sulfur coordination prior to C-S insertion.
Download or read book Transition Metal Activation and Functionalization of Carbon hydrogen Bonds Progress Report December 1 1989 November 30 1992 written by and published by . This book was released on 1992 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: We are investigating the fundamental thermodynamic and kinetic factors that influence carbon-hydrogen bond activation at homogeneous transition metal centers and the conversion of hydrocarbons into functionalized products of potential use to the chemical industry. Advances have been made in both understanding the interactions of hydrocarbons with metals and in the functionalization of hydrocarbons. We have found that RhCl(PR3)2(CNR) complexes can catalyze the insertion of isonitriles into the C-H bonds or arenes upon photolysis. The mechanism of these reactions was found to proceed by way of initial phosphine dissociation, followed by C-H activation and isonitrile insertion. We have also examined reactions of a series of arenes with (C5Me5)Rh(PMe3)PhH and begun to map out the kinetic and thermodynamic preferences for arene coordination. The effects of resonance, specifically the differences in the Hueckel energies of the bound vs free ligand, are now believed to fully control the C-H activation/?2-coordination equilibria. We have begun to examine the reactions of rhodium isonitrile pyrazolylborates for alkane and arene C-H bond activation. A new, labile, carbodiimide precursor has been developed for these studies. We have completed studies of the reactions of (C5Me5)Rh(PMe3)H2 with D2 and PMe3 that indicate that both?5 2!?3 ring slippage and metal to ring hydride migration occur more facilely than thermal reductive elimination of H2. We have examined the reactions of heterocycles with (C5Me5)Rh(PMe3)PhH and found that pyrrole and furan undergo C-H or N-H activation. Thiophene, however, undergoes C-S bond oxidative addition, and the mechanism of activation has been shown to proceed through sulfur coordination prior to C-S insertion.
Download or read book Transition Metal Activation and Functionalization of Carbon hydrogen Bonds Progress Report December 1 1992 November 30 1993 written by and published by . This book was released on 1993 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: A method was developed for synthesizing a new complex for studying C-H activation, (HBPz*3)Rh(CNCH2CMe3)(PhN=C=NCH2CMe3). This complex loses the carbodiimide ligand, thereby serving as a precursor for a 16-electron Rh(I) fragment which activates (via oxidative addition) a wide range of aromatic and aliphatic C-H bonds. Mechanism of activation of benzene by this fragment was studied. Reaction of [TpR̀h(CNR)] fragment with aliphatic hydrocarbons was also studied. A study of C-H bond activation by the complex MnH3(dmpe)2 was completed. Reactions of [Ru(dmpe)2] with several small molecules were also investigated. Effects of fluorine substituents on aromatic ring on C-H activation were looked at. Studies of?2-arene coordination with [(C5Me5)Rh(PMe3)] were completed; studies of reaction of this complex with 1,3-disubstituted benzenes are in progress.
Download or read book C H Activation for Asymmetric Synthesis written by Françoise Colobert and published by John Wiley & Sons. This book was released on 2019-11-11 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides, in one handbook, comprehensive coverage of one of the hottest topics in stereoselective chemistry Written by leading international authors in the field, this book introduces readers to C-H activation in asymmetric synthesis along with all of its facets. It presents stereoselective C-H functionalization with a broad coverage, from outer-sphere to inner-sphere C-H bond activation, and from the control of olefin geometry to the induction of point, planar and axial chirality. Moreover, methods wherein asymmetry is introduced either during the C-H activation or in a different elementary step are discussed. Presented in two parts?asymmetric activation of C(sp3)-H bonds and stereoselective synthesis implying activation of C(sp2)-H bonds?CH-Activation for Asymmetric Synthesis showcases the diversity of stereogenic elements, which can now be constructed by C-H activation methods. Chapters in Part 1 cover: C(sp3)-H bond insertion by metal carbenoids and nitrenoids; stereoselective C-C bond and C-N bond forming reactions through C(sp3)?H bond insertion of metal nitrenoids; enantioselective intra- and intermolecular couplings; and more. Part 2 looks at: C-H activation involved in stereodiscriminant step; planar chirality; diastereoselective formation of alkenes through C(sp2)?H bond activation; amongst other methods. -Covers one of the most rapidly developing fields in organic synthesis and catalysis -Clearly structured in two parts (activation of sp3- and activation of sp2-H bonds) -Edited by two leading experts in C-H activation in asymmetric synthesis CH-Activation for Asymmetric Synthesis will be of high interest to chemists in academia, as well as those in the pharmaceutical and agrochemical industry.
Download or read book C H Activation written by Jin-Quan Yu and published by Springer. This book was released on 2010-06-16 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Table of Contents - Synthesis in the Key of Catellani: Norbornene-Mediated ortho C–H Functionalization - Mechanistic Considerations in the Development and Use of Azine, Diazine and Azole N-Oxides in Palladium-Catalyzed Direct Arylation - Palladium and Copper Catalysis in Regioselective, Intermolecular Coupling of C–H and C–Hal Bonds - Pd-Catalyzed C–H Bond Functionalization on the Indole and Pyrrole Nucleus - Remote C–H Activation via Through-Space Palladium and Rhodium Migrations - Palladium-Catalyzed Aryl–Aryl Bond Formation Through Double C–H Activation - Palladium-Catalyzed Allylic C–H Bond Functionalization of Olefins - Ruthenium-Catalyzed Direct Arylations Through C–H Bond Cleavages - Rhodium-Catalyzed C–H Bond Arylationof Arenes - Cross-Dehydrogenative Coupling Reactions of sp3-Hybridized C–H Bonds - Functionalization of Carbon–Hydrogen Bonds Through Transition Metal Carbenoid Insertion - Metal-Catalyzed Oxidations of C–H to C–N Bonds
Download or read book Remote C H Bond Functionalizations written by Debabrata Maiti and published by John Wiley & Sons. This book was released on 2021-04-26 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt: A guide to contemporary advancements in the field of distal C-H functionalizations An important and dynamic topic within the modern field of organic synthesis, selective functionalization of C-H bonds can be used in a variety of applications across the pharmaceutical and agrochemical industries. Remote C-H Bond Functionalizations presents an inclusive account of the most recent developments and potential applications of performing variegated functionalizations selectively at the distal positions of organic compounds. Featuring contributions by an international team of experts, this authoritative volume provides deep insight into distal functionalizations, including detailed discussion of mechanisms, the engineering of templates, and the design of strategies. The text covers a diverse range of topics including C-H functionalization of palladium/norbornene catalysis, ruthenium-catalyzed remote functionalization, the non-directed distal C(sp2)-H, functionalization, transition metal catalyzed distal para-selective C-H functionalization, and much more. Reviewing contemporary advancements in the field while laying the foundation for future research, this important resource: Provides the most recent research and thorough coverage of the subject available in a single volume Offers practical information on C-H functionalizations in various industries Includes an up-to-date introduction to distal C-H functionalizations Remote C-H Bond Functionalizations is a must-read for every synthetic chemist, including chemists working with organometallics, organic chemists and researchers, and industrial chemists.
Download or read book Transition Metal catalyzed Functionalization of Carbon hydrogen Bonds in Alkenes written by Xiaolin Qian and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Alkenes can undergo a variety of chemical reactions to form more complex molecules with a range of functional groups. This makes them useful starting materials for synthesizing a wide range of organic compounds. Chapter I provided an overview of the development history of alkenyl C8́2H bond activation. The early reactions of C8́2H compounds with metal complexes, as well as stoichiometric activation of the transition metal-activated C-H bond, were discussed. Then the first successful and efficient organometallic-catalyzed transformations of a C8́2H bond, the first transition metal-catalyzed vinylic C-H functionalization, and the first transition metal-catalyzed olefinic C-H functionalization under mild conditions were demonstrated. Finally, enantioselective vinylic C-H functionalization was discussed. In Chapter II, a method for enantioselective vinylic C(sp2)8́2H bond activation using a Ru(II) catalyst and a chiral transient directing group was developed. Chiral amine was also utilized to control the Z/E stereoselectivity. The method demonstrated a broad substrate scope with good yield, high Z/E ratio stereoselectivity, and excellent enantioselectivity. Its synthetic utility was demonstrated by the synthesis of key structural motifs of particularly useful natural products and pharmaceutical compounds. Additionally, a rare vinylic C8́2H bond activated ruthenic complex was isolated and determined by single-crystal X-ray diffraction. The methodology suggested in this work is expected to facilitate the further development of asymmetric vinylic C8́2H functionalization reactions. In Chapter III, a practical and efficient methodology for Ru(II)-catalyzed enantioselective alkenyl C-H bond functionalization of indole-substituted acrylaldehyde derivatives via the chiral transient directing group (CTDG) strategy to obtain optically active pyrrolo[1,2-a]indole derivatives was suggested. The methodology resulted in a series of optically active products with good yields (up to 80%), good stereoselectivity (up to 25.0:1 Z/E), and excellent enantioselectivity (up to 95% ee). Furthermore, synthetic transformations were explored. Chapter IV presented the first demonstration of a sequentially composed catalytic substitution reaction of alkenes for building multi-amido methylated derivatives while reserving the Ï0- components. The process involved a simple Fe (III)-catalyst and bisamidomethane reagent, which directly and selectively transformed Îł-substituted styrenes into several biologically and pharmaceutically relevant N-heterocycles through tandem processes.
Download or read book C H Bond Activation and Catalytic Functionalization II written by Pierre H. Dixneuf and published by Springer. This book was released on 2016-03-10 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: The series Topics in Organometallic Chemistry presents critical overviews of research results in organometallic chemistry. As our understanding of organometallic structure, properties and mechanisms increases, new ways are opened for the design of organometallic compounds and reactions tailored to the needs of such diverse areas as organic synthesis, medical research, biology and materials science. Thus the scope of coverage includes a broad range of topics of pure and applied organometallic chemistry, where new breakthroughs are being achieved that are of significance to a larger scientific audience. The individual volumes of Topics in Organometallic Chemistry are thematic. Review articles are generally invited by the volume editors. All chapters from Topics in Organometallic Chemistry are published OnlineFirst with an individual DOI. In references, Topics in Organometallic Chemistry is abbreviated as Top Organomet Chem and cited as a journal.
Download or read book Activation and Functionalization of C H Bonds written by Karen I. Goldberg and published by ACS Symposium. This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Activation and Functionalization of C-H Bonds explores recent developments in the reaction chemistry of solution-phase transition-metal based systems with simple hydrocarbons and with more complex organic molecules. More than 20 internationally leading research groups contributed to this volume, and their chapters cover such topics as fundamental theoretical and mechanistic studies of C-H bond activation by metal complexes, catalytic systems for alkane functionalization, and new applications in synthetic organic chemistry. An introductory chapter offers an overview of stoichiometric and catalytic reactions of C-H bonds with transition metal complexes. The C-H bond is the most widespread linkage in organic chemistry, present in virtually every organic molecule. Unfortunately, C-H bonds are famously resistant to selective chemical transformations. The development of methods for their selective transformations has enormous potential value in fields ranging from the chemistry of fuels (for example, the conversion of methane to methanol) to the synthesis of the most complex organic molecules.
Download or read book C H and C X Bond Functionalization written by Xavi Ribas and published by Royal Society of Chemistry. This book was released on 2013-05-24 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cross-coupling reactions involving C-H and C-X bond functionalisation are commonplace in natural product synthesis and natural products, therapeutic agents, biological probes, and advanced materials. Much attention has been given to understanding the mechanistic strategies used to achieve this, making this a hot topic in recent years. In this edited book, contributions from across the globe examine these strategies, with a particular focus on palladium and copper, as well as iron – an emerging element in this field. Reviewing the recent literature, the book presents an in-depth understanding of the field, guiding the reader to achieving the best synthetic strategies for aromatic functionalisation. Organic and Organometallic chemists, as well as natural product and pharmaceutical scientists, will find this an essential guide to a major transformation currently underway in synthetic chemistry.
Download or read book C H Activation written by Jin-Quan Yu and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Table of Contents - Synthesis in the Key of Catellani: Norbornene-Mediated ortho C-H Functionalization - Mechanistic Considerations in the Development and Use of Azine, Diazine and Azole N-Oxides in Palladium-Catalyzed Direct Arylation - Palladium and Copper Catalysis in Regioselective, Intermolecular Coupling of C-H and C-Hal Bonds - Pd-Catalyzed C-H Bond Functionalization on the Indole and Pyrrole Nucleus - Remote C-H Activation via Through-Space Palladium and Rhodium Migrations - Palladium-Catalyzed Aryl-Aryl Bond Formation Through Double C-H Activation - Palladium-Catalyzed Allylic C-H Bond Functionalization of Olefins - Ruthenium-Catalyzed Direct Arylations Through C-H Bond Cleavages - Rhodium-Catalyzed C-H Bond Arylationof Arenes - Cross-Dehydrogenative Coupling Reactions of sp3-Hybridized C-H Bonds - Functionalization of Carbon-Hydrogen Bonds Through Transition Metal Carbenoid Insertion - Metal-Catalyzed Oxidations of C-H to C-N Bonds.
Download or read book Alkane C H Activation by Single Site Metal Catalysis written by Pedro J. Pérez and published by Springer Science & Business Media. This book was released on 2012-09-15 with total page 277 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decade, much research effort has been devoted to the design and synthesis of new reagents and catalysts that can influence carbon-hydrogen bond activation, mainly because of the prospect that C−H activation could enable the conversion of cheap and abundant alkanes into valuable functionalized organic compounds. Alkane C-H Activation by Single-Site Metal Catalysis presents the current state-of-the-art development in the catalytic systems for the catalytic trans-formations of alkanes under homogeneous conditions. Chapter 1 offers a comprehensive summary of the main discoveries realized so far. Chapter 2 reviews the so-called electrophilic activation, initiated by Shulpín in the late 60s, and the base for the Catalytica system. Chapter 3 examines the catalytic borylation of alkanes, discovered by Hartwig, whereas chapter 4 provides an updated vision of the alkane dehydrogenation reaction. Chapter 5 covers the oxygenation of C-H bonds, a field of enormous interest with bioinorganic im-plications, and finally chapter 6 presents the functionalization of alkane C-H bonds by carbene or nitrene insertion. The history of C-H bond activation, and the current research described in this book, highlight the current research and present the reader with an outlook of this field which continues to be explored by an increasingly visionary and enthusiastic group of organic, organometallic, biological and physical chemists.
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 Transition Metal Catalyzed C H Functionalization of Heterocycles 2 Volumes written by Tharmalingam Punniyamurthy and published by John Wiley & Sons. This book was released on 2023-03-28 with total page 1209 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transition-Metal-Catalyzed C-H Functionalization of Heterocycles A comprehensive guide to recent advances in this field Constituting the majority of all known compounds, heterocycles are structures that incorporate one or more heteroatoms within their core, thus exhibiting properties that are quite different from their all-carbon analogs. They are fundamental to all fields of chemistry and, therefore, their synthesis and modification has attracted a great deal of attention in the recent years. In this vein, transition-metal-catalyzed C-H bond functionalization forms a crucial tool for generating and analyzing heterocyclic compounds. Transition-Metal-Catalyzed C-H Functionalization of Heterocycles, Two-Volume Set, showcases diverse C-H functionalization methodologies and their incorporation into the latest research. The chapters serve as an essential tool depicting detailed site-selective functionalization of heterocyclic cores, along with a comprehensive discussion on their mechanistic approaches. Readers of Transition-Metal-Catalyzed C-H Functionalization of Heterocycles, Two-Volume-Set will also find: A detailed introduction to C-H activation along with the mechanistic aspects of transition-metal-catalyzed C-H bond activation reactions Easy-to-use structures with each chapter dedicated to a type of heterocycle and its specific functionalization methodologies A leading team of international authors in C-H bond functionalization Transition-Metal-Catalyzed C-H Functionalization of Heterocycles, Two-Volume-Set is a valuable guide for students and researchers in organic synthesis and process development, in both academic and industrial contexts.
Download or read book Sustainable C sp3 H Bond Functionalization written by Jin Xie and published by Springer. This book was released on 2016-02-29 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights major achievements made in the last five years concerning sustainable C(sp3)-H bond functionalization and offers a promising and emerging tool-kit for organic synthesis. The book is divided into three chapters demonstrating key advances in C(sp3)-H bond functionalization. Chapter 1 reviews transition-metal-catalyzed C(sp3)-H bond functionalization using different directing groups, while Chapter 2 addresses the new methods of transition-metal-catalyzed and metal-free C(sp3)-H bond functionalization without directing groups, in addition to briefly highlighting redox-neutral C(sp3)-H bond functionalization. In closing, Chapter 3 examines visible-light photoredox catalysis, an emerging and highly sustainable C(sp3)-H bond functionalization strategy. The book offers an intriguing and useful reference guide for a broad readership working and/or interested in the fields of organic, organometallic, and green chemistry.
Download or read book Activation of Carbon Hydrogen Bonds by Transition Metal Compounds written by Jeffrey Ira Melzer and published by . This book was released on 1982 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transition Metal Mediated Synthesis of Heterocycles Via Carbon hydrogen Bond Activation written by Ling Li and published by . This book was released on 2009 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt:
