Download or read book Expanding the Scope of Ruthenium based Olefin Metathesis Catalysts written by Matthias Scholl and published by . This book was released on 2000 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ruthenium based Olefin Metathesis Catalysts written by Eric Lee Kuiokalani Dias and published by . This book was released on 1998 with total page 113 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ruthenium based Olefin Metathesis Catalysts Coordinated with N heterocyclic Carbene Ligands written by John Philip Morgan and published by . This book was released on 2003 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ruthenium based Olefin Metathesis Catalysts Bearing PH responsive Ligands written by Shawna Lynn Balof and published by . This book was released on 2011 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis and Application of New Ruthenium Based Olefin Metathesis Catalysts written by Roman Savka and published by . This book was released on 2014 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Design and Synthesis of Ruthenium Indenylidene based Catalysts for Olefin Metathesis written by César A. Urbina-Blanco and published by . This book was released on 2013 with total page 183 pages. Available in PDF, EPUB and Kindle. Book excerpt: As part of a European wide effort to develop metathesis catalysts for use in fine chemical and pharmaceutical compound synthesis, this study focuses on the design and synthesis of ruthenium based catalysts for olefin metathesis. The aim, of this work was simple: to develop new, more active, more stable, easy to synthesise and commercially viable Ruthenium based catalysts, as well trying to rationalize the effect of structural changes on reactivity. Two different approaches were explored in order to develop more active catalysts bearing N-heterocyclic carbene (NHC) ligands: changing the leaving group and the effect of the NHC moiety in indenylidene type complexes. Over 12 new catalysts were developed and their activity compared to that of commercially available catalysts. Overall, the new complexes exhibited superior reactivity compared to previously reported catalysts in several benchmark transformations. However, olefin metathesis is a very substrate specific reaction, and rather than finding one catalyst that is superior to all, a catalogue of catalysts suitable for specific transformations was developed. In addition, the effect of structural changes on substrate activity was investigated in the ring closing metathesis of 1,8-nonadienes. The reaction profiling showcased the presence of a gem-difluoro group as an accelerating group in this incarnation of the olefin metathesis reaction and leads to ring formation over polymerization. In order to rationalize the effect of structural changes on catalyst activity, kinetic studies dealing with the initiation mechanism of ruthenium-indenylidene complexes were examined and compared with that of benzylidene counterparts. It was discovered that not all indenylidene complexes followed the same mechanism, highlighting the importance of steric and electronic properties of so-called spectator ligands, and that there is no single mechanism for the ruthenium-based olefin metathesis reaction. These results highlight the importance of systematic development of catalysts and that as scientists we should not take for granted.
Download or read book Handbook of Metathesis 3 Volume Set written by Robert H. Grubbs and published by John Wiley & Sons. This book was released on 2015-05-26 with total page 1639 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covering the complete breadth of the olefin metathesis reaction. The second edition of the ultimate reference in this field is completely updated and features more than 80% new content, with the focus on new developments in the field, especially in industrial applications. No other book covers the topic in such a comprehensive manner and in such high quality, and this new edition retains the three-volume format: Catalyst Development, Applications in Organic Synthesis and Polymer Synthesis. Edited by a Nobel laureate in the field, and with a list of contributors that reads like a "Who's-Who" of metathesis, this is an indispensable one-stop reference for organic, polymer and industrial chemists, as well as chemists working with organometallics. Individual volumes also available separately to purchase Volume 1: Catalyst Development - http://www.wiley.com/WileyCDA/WileyTitle/productCd-3527339485.html Volume 2: Applications in Organic Synthesis - http://www.wiley.com/WileyCDA/WileyTitle/productCd-3527339493.html Volume 3: Polymer Synthesis - http://www.wiley.com/WileyCDA/WileyTitle/productCd-3527339507.html
Download or read book Olefin Metathesis and Metathesis Polymerization written by K. J. Ivin and published by Elsevier. This book was released on 1997-01-07 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a follow-up to Ivins Olefin Metathesis, (Academic Press, 1983). Bringing the standard text in the field up to date, this Second Edition is a result of rapid growth in the field, sparked by the discovery of numerous well-defined metal carbene complexes that can act as very efficient initiators of all types of olefin metathesis reaction, including ring-closing metathesis of acyclic dienes, enynes, and dienynes; ring-opening metathesis polymerizationof cycloalkenes, acyclic diene metathesis polymerization; and polymerization of alkynes, as well as simple olefin metathesis. Olefin Metathesis and Metathesis Polymerization provides a broad, up-to-date account of the subject from its beginnings in 1957 to the latest applications in organic synthesis. The book follows the same format as the original, making it useful toteachers and to researchers, and will be of particular interest to those working in the fields of organic chemistry, polymer chemistry, organometallic chemistry, catalysis, materials science and chemical engineering. Discusses different classes of olefin metathesis and the choice of reaction conditions and catalyst Considers commercial processes with examples from existing and new technologies Provides a complete overview of the subject from its beginning to the present day
Download or read book Handbook of Metathesis Volume 1 written by Robert H. Grubbs and published by John Wiley & Sons. This book was released on 2015-02-18 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: The second edition of the Handbook of Metathesis, edited by Nobel Prize Winner Robert H. Grubbs and his team, is available as a 3 Volume set as well as individual volumes. Volume 1, edited by R. H. Grubbs together with A. G. Wenzel focusses on Catalyst Development and Mechanism. The new edition of this set is completely updated (more than 80% new content) and expanded, with a special focus on industrial applications. Written by the "Who-is-Who" of metathesis, this book gives a comprehensive and high-quality overview. It is the perfect and ultimate one-stop-reference source in this field and indispensable for chemists in academia and industry alike. View the set here - http://www.wiley.com/WileyCDA/WileyTitle/productCd-3527334246.html Other available volumes: Volume 2: Applications in Organic Synthesis, Editors: R. H. Grubbs and D. J. O´Leary - http://www.wiley.com/WileyCDA/WileyTitle/productCd-3527339493.html Volume 3: Polymer Synthesis, Editors: R. H. Grubbs and E. Khosravi - http://www.wiley.com/WileyCDA/WileyTitle/productCd-3527339507.html
Download or read book Ligand Design in Metal Chemistry written by Mark Stradiotto and published by John Wiley & Sons. This book was released on 2016-09-01 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: The design of ancillary ligands used to modify the structural and reactivity properties of metal complexes has evolved into a rapidly expanding sub-discipline in inorganic and organometallic chemistry. Ancillary ligand design has figured directly in the discovery of new bonding motifs and stoichiometric reactivity, as well as in the development of new catalytic protocols that have had widespread positive impact on chemical synthesis on benchtop and industrial scales. Ligand Design in Metal Chemistry presents a collection of cutting-edge contributions from leaders in the field of ligand design, encompassing a broad spectrum of ancillary ligand classes and reactivity applications. Topics covered include: Key concepts in ligand design Redox non-innocent ligands Ligands for selective alkene metathesis Ligands in cross-coupling Ligand design in polymerization Ligand design in modern lanthanide chemistry Cooperative metal-ligand reactivity P,N Ligands for enantioselective hydrogenation Spiro-cyclic ligands in asymmetric catalysis This book will be a valuable reference for academic researchers and industry practitioners working in the field of ligand design, as well as those who work in the many areas in which the impact of ancillary ligand design has proven significant, for example synthetic organic chemistry, catalysis, medicinal chemistry, polymer science and materials chemistry.
Download or read book Zeolite Microporous Solids Synthesis Structure and Reactivity written by E.G. Derouane and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 635 pages. Available in PDF, EPUB and Kindle. Book excerpt: Intensive research on zeolites, during the past thirty years, has resulted in a deep understanding of their chemistry and in a true zeolite science, including synthesis, structure, chemical and physical properties, and catalysis. These studies are the basis for the development and growth of several industrial processes applying zeolites for selective sorption, separation, and catalysis. In 1983, a NATO Advanced Study Institute was organized in Alcabideche (portugal) to establish the State-of-the-Art in Zeolite Science and Technology and to contribute to a better understanding of the structural properties of zeolites, the configurational constraints they may exert, and their effects in adsorption, diffusion, and catalysis. Since then, zeolite science has witnessed an almost exponential growth in published papers and patents, dealing with both fundamentals issues and original applications. The proposal of new procedures for zeolite synthesis, the development of novel and sophisticated physical techniques for zeolite characterization, the discovery of new zeolitic and related microporous materials, progresses in quantum chemistry and molecular modeling of zeolites, and the application of zeolites as catalysts for organic reactions have prompted increasing interest among the scientific community. An important and harmonious interaction between various domains of Physics, Chemistry, and Engineering resulted therefrom.
Download or read book Carbenes in Ruthenium Based Olefin Metathesis Catalysts and Stabilization of Low Coordinate Boron Species written by Fatme Dahcheh and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Organometallic Chemistry in Industry written by Thomas J. Colacot and published by John Wiley & Sons. This book was released on 2020-05-26 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: Showcases the important role of organometallic chemistry in industrial applications and includes practical examples and case studies This comprehensive book takes a practical approach to how organometallic chemistry is being used in industrial applications. It uniquely offers numerous, real-world examples and case studies that aid working R&D researchers as well as Ph.D. and postdoc students preparing to ace interviews in order to enter the workforce. Edited by two world-leading and established industrial chemists, the book covers flow chemistry (catalytic and non-catalytic organometallic chemistry), various cross-coupling reactions (C-C, C-N, and C-B) in classical batch chemistry, conjugate addition reactions, metathesis, and C-H arylation and achiral hydrogenation reactions. Beginning with an overview of the many industrial milestones within the field over the years, Organometallic Chemistry in Industry: A Practical Approach provides chapters covering: the design, development, and execution of a continuous flow enabled API manufacturing route; continuous manufacturing as an enabling technology for low temperature organometallic chemistry; the development of a nickel-catalyzed enantioselective Mizoroki-Heck coupling; and the development of iron-catalyzed Kumada cross-coupling for the large scale production of Aliskiren intermediates. The book also examines aspects of homogeneous hydrogenation from industrial research; the latest industrial uses of olefin metathesis; and more. -Includes rare industrial case studies difficult to find in current literature -Helps readers successfully carry out their own reactions -Covers topics like flow chemistry, cross-coupling reactions, and dehydrative decarbonylation -Features a foreword by Nobel Laureate R. H. Grubbs -A perfect resource for every R&D researcher in industry -Useful for PhD students and postdocs: excellent preparation for a job interview Organometallic Chemistry in Industry: A Practical Approach is an excellent resource for all chemists, including those working in the pharmaceutical industry and organometallics.
Download or read book Olefin Metathesis written by Karol Grela and published by John Wiley & Sons. This book was released on 2014-04-11 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a complete examination of the theory and methods ofmodern olefin metathesis, one of the most widely used chemicalreactions in research and industry. Provides basic information for non-specialists, while alsoexplaining the latest trends and advancements in the field toexperts Discusses the various types of metathesis reactions, includingCM, RCM, enyne metathesis, ROMP, and tandem processes, as well astheir common applications Outlines the tools of the trade—from the importantclasses of active metal complexes to optimal reactionconditions—and suggests practical solutions for commonreaction problems Includes tables with structures of commercial catalysts, andrecommendations for commercial catalyst suppliers
Download or read book Longer lived Olefin Metathesis Catalysts Based on Molybdenum and Ruthenium written by Joseph Yoon and published by . This book was released on 2020 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: The field of olefin metathesis has seen considerable growth in the recent past. Some of the earliest milestones in the field include the synthesis of well-defined catalysts based on molybdenum, tungsten, and ruthenium. The efficiencies of these catalysts, however, are limited by their decomposition. Efforts have been made to increase the lifetime of these catalysts by changing the ligand sphere, to stabilize catalytic intermediates. Examples include the employment of the N-heterocyclic carbene (NHC) and the chelating (o-isopropoxy)benzylidene ligand seen in the second-generation Grubbs and Hoveyda catalysts. Processes that utilize the olefin metathesis processes, like those in the petroleum industry and large-scale production of chemicals, are bound by the need for high catalyst loadings which translate to high costs. The work herein presents the pursuit of longer-lived olefin metathesis catalysts based on molybdenum and ruthenium. The first goal of this thesis project was to develop a stable molybdenum-based olefin metathesis catalyst supported by a tridentate PONOP ligand and a chelating (o- x methoxy)benzylidene ligand. Previous attempts in our lab employed nonchelating alkylidene initiators - yielding no success in isolation. The rationale behind this design was that a chelating ether moiety will stabilize the molybdenum-center enough to be isolable. Attempts to isolate the chelating molybdenum-alkylidene species were also unsuccessful. Instead, we probed the in-situ ROMP of norbornene using iPrPONOP MoCl3 as a precatalyst and (2-methoxybenzyl)magnesium chloride as a cocatalyst. This cocatalyst did not lend any improvements to the simpler nonchelating Grignard cocatalysts. The synthesis of a novel dialkyl zirconocene complex is also reported. The second and more heavily pursued endeavor was the development of longer-lived ruthenium olefin metathesis catalysts. Specifically, we aimed at improving the second-generation Hoveyda catalyst with the use of a hemilabile tridentate NHC ligand. Two novel catalysts bearing NHC ligands with a hemilabile ethoxy-pyridyl arm were synthesized along with their unique organic frameworks. The catalyst containing the 2,6-diisopropylphenyl group (C1-Me) was investigated more comprehensively because it was more readily prepared. This complex was characterized by high thermal stability under metathesis conditions and remarkable TONs in the self-metathesis of 1-decene. In our efforts to prepare C1-Me without utilizing a Grubbs I intermediate, a new complex (6) bearing our NHC ligand was isolated and characterized by 1H NMR and single crystal x-ray diffraction spectroscopy. The reaction of C1-Me with ethylene did not produce the desired C1-Me-methylidene variant - however, the same reaction with propylene gave C1-Me-ethylidene with relative ease. Analyzing the active catalytic species under the metathesis of 1-decene revealed that the resting state of the catalyst is not the expected methylidene, but rather the longer chain nonylidene. xi Initiation studies were conducted to compare the rates of initiation for catalyst C1-Me and the nonmethylated C1-H. First, the rate of metathesis was followed in the irreversible reaction with ethyl vinyl ether. Second, ligand exchange equilibrium experiments were carried out to compare the dissociation constants for the pyridyl moieties in both catalysts. The outcome of these studies revealed that catalyst C1-Me, with a methyl group in the phenoxide ring, exhibits a 10-fold increase in initiation versus the nonmethylated C1-H catalyst. The NHC ligand scaffold reported in this work may assist in the development of other inorganic and organometallic catalytic systems, as many rely on the use of ancillary ligands for support. Furthermore, fixing a hemilabile ethoxy-pyridyl arm onto already robust systems, such as ruthenium catalysts bearing a cyclic alkyl amino carbene ligand, may offer even greater catalytic turnover numbers (TONs).
Download or read book Metathesis Polymerization of Olefins and Polymerization of Alkynes written by Yavuz İmamoğlu and published by Springer Science & Business Media. This book was released on 1998 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains contributions from inorganic, organic and polymer chemists, who join forces to report on the state of the art in ring opening metathesis polymerization, acyclic diene metathesis and alkyne polymerization. Topics covered are: mechanism of ROMP reactions, new catalysts for ROMP, new products by ROMP, new catalysts for ADMET, new products by ADMET, degradation of polymers by metathesis reactions, alkyne polymerization and metathesis, and industrial applications of metathesis reactions.
Download or read book Electronic Structure Studies of Ruthenium based Catalysts for Olefin Metathesis written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Interest in olefin metathesis has increased over the years with the development of ruthenium-based catalysts. Their unique properties have allowed their use in numerous industrial and laboratory processes in relatively mild conditions and in combination with a wide range of solvents. Several studies have provided insights into how these catalysts work, but very little has been done in order to understand why they work that way; an important aspect that has the potential of benefiting chemists while designing new catalysts. The research introduced here has focused on the fundamental understanding of their reactivity by exploring their electronic structure, using a combination of synchrotron-based X-ray-absorption (XAS) techniques in combination with DFT calculations and multiplet simulations. As part of the experimental work, samples from various ruthenium-based catalysts classified as first-generation (whenever the ancillary ligand is a phosphine) or as second-generation analogues (whenever this ligand is an N-heterocyclic carbene, NHC) were used. The Ru K-edge XAS data have revealed that the ruthenium centre in second-generation analogues is more positively charged than the corresponding first-generation counterparts. This offers a rationale for previously observed kinetic results, which have shown a slower initial step for the second-generation Grubbs catalyst. At the same time, they raise questions in a more fundamental level on whether or not NHCs are truly better charge donors than phosphine ligands. DFT results are consistent and the ongoing analyses of the Cl K- and C K-edge XAS data indicate similar overall bonding structures between first- and second- generation analogues. In addition, from preliminary results on these edges, two possible identities of substantially different nature have emerged for the LUMO orbital. In this regard, the final conclusion should provide important insights on through which orbital the metathesis reaction gets started. As a sid.
