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Book Synthesis and Reactivity of High Oxidation State Molybdenum Catalysts for Ring Opening Metathesis Polymerization of Olefins

Download or read book Synthesis and Reactivity of High Oxidation State Molybdenum Catalysts for Ring Opening Metathesis Polymerization of Olefins written by Guillermo Carlos Bazan and published by . This book was released on 1990 with total page 664 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Synthesis and Reactivity of High Oxidation State Tungsten and Molybdenum Olefin Metathesis Catalysts Bearing New Imido Ligands

Download or read book Synthesis and Reactivity of High Oxidation State Tungsten and Molybdenum Olefin Metathesis Catalysts Bearing New Imido Ligands written by Jonathan Clayton Axtell and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Chapter 1 details the synthesis of tungsten imidoalkylidene compounds bearing strongly electron-withdrawing imido ligands. An alternative synthesis involving the treatment of WCl6 with 4 equivalents of N-trimethylsilyl-substituted anilines and subsequent workup with 1,2-dimethoxyethane (DME) has been employed to form complexes of the type W(NAr)2C12(dme); syntheses employing WO2C 2(dme) as the tungsten precursor were unsuccessful. Alkylation with neopentylmagnesium chloride (ClMgNp) and subsequent treatment with trifluoromethanesulfonic acid (HOTf) affords imidoalkylidene species W(NAr)(CHCMe 3)(OTf)2(dme) (OTf = trifluoromethanesulfonate); analogous neophylidene ([W]CHCMe 2Ph) species could not be made under these conditions. Treatment of these compounds with two equivalents of LiO(2,6-(CHCPh 2)C6H3)-Et2O affords the bisaryloxide complexes of the type W(NAr)(CHCMe3)(OR)2. Ring-Opening Metathesis Polymerization (ROMP) studies using a series of these bisaryloxides show that rates of ROMP increase as the electron-withdrawing power of the substituents on the imido ligand increase if steric bulk about the metal center is held constant. A similar trend between two bisaryloxides is observed for anti-to-syn alkylidene rotation rates at 50*C in toluene-d8 . Difficulties synthesizing bis-pyrrolide complexes of the type W(NAr)(CHCMe3)(pyr)2 precluded their use as catalyst precursors; some MAP species containing the more sterically encumbering 2,5-dimethylpyrrolide ligand are presented and the metathesis activity of MAP species bearing the 2,5-dimethylpyrrolide ligand is discussed. Chapter 2 introduces Mo and W complexes bearing the current extreme in sterically bulky imido ligands, the NHIPT (HIPT = 2,6-(2,4,6-iPr 3CH2)CH3) ligand, in an effort to generate all anti alkylidene species. A non-traditional synthetic route is employed in order to install this ligand first as an anilide, and after subsequent proton transfer, as an imido ligand to form a mixed imido species of the type M(NHIPT)(N'Bu)(NH'Bu)Cl. Addition of one equivalent of 2,6-lutidinium chloride, followed by alkylation affords dialkyl species M(NHIPT)(N'Bu)Np 2, and treatment with three equivalents of pyridinium chloride yields all anti imidoalkylidene dichloride species as mono-pyridine adducts, M(NHIPT)(CHCMe 3)C 2(py) (M = Mo, W). General reactivity, including strategies for removal of the pyridine adduct as well as substitution and metathesis chemistry, are discussed. ROMP of MPCP (MPCP = 3-methyl-3-phenylcyclopropene) by a Mo-based MAP species bearing the NHIPT ligand yields predominantly cis,syndiotactic poly(MPCP) and in the homo-metathesis of 1 -octene yields ~81% cis-7-tetradecene. The possible source of trans olefinic product is addressed. Chapter 3 presents the synthesis of the first (1-adamantyl)imido species of tungsten. The functional equivalent of common bisimido precursors for other Mo/W alkylidene species, [W(NAd) 2C 2(AdNH2)1 2, is shown to be a dimer stabilized by hydrogen-bonding interactions between adamantylamine protons and adjacent chlorides bound to the second metal of the dimer. Subsequent alkylation with ClMgNp affords the expected dialkyl species, and treatment with three equivalents of 3,5-lutidinium chloride affords imidoalkylidene complex W(NAd)(CHCMe 3)(C) 2(lut)2 (lut = 3,5-dimethylpyridine). The most desirable synthetic route toward monoalkoxide pyrrolide (MAP) species proceeds through a monoaryloxide monochloride intermediate W(NAd)(CHCMe 3)(Cl)(OAr)(lut) (Ar = 2,6-(2,4,6-Me 3)C6H3, 2,6-(2,4,6-'Pr 3)C6H3). Removal of lutidine with B(C6 F5 )3 and subsequent treatment with lithium pyrrolide affords W(NAd)(CHCMe3)(pyr)(OAr) (pyr = pyrrolide); 2,5-dimethylpyrrolide analogues (W(NAd)(CHCMe3)(Me2pyr)(OAr) can be accessed via protonolysis by HOAr from W(NAd)(CHCMe3)(Me2pyr)2(lut).

Book Olefin Metathesis and Polymerization Catalysts

Download or read book Olefin Metathesis and Polymerization Catalysts written by Yavuz Imamogammalu and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 567 pages. Available in PDF, EPUB and Kindle. Book excerpt: Olefin metathesis reaction can be considered as one of the most successful organic reactions with many applications in the low molecular weight range and also in the polymer field. The use of catalysts with their selective and effective transformation properties in olefin metathesis I polymerization systems is a growing interest. There has been great effort and competition in developing active and commercially useful catalysts. The main aim of this ASI was to gather several research groups and also the people from industry. to present existing knowledge and latest results in the field. A wide range of topics through homogeneous and heterogeneous aspects have been considered. Attention has been drawn to the metal-carbene and metallacyclobutane complexes as active species, the initiation mechanisms, the stereochemistry and thermodynamics of these reactions. New catalytic systems for the metathesis of alkenes and alkynes and fot' ring opening polymeriZation I block copolymerization reactions have been introduced. Spectroscopic studies for the characteriZation of catalysts, simulation studies explaining the function of chain carrier species and polymer degradation have also been covered. A detailed industrial report concerning the patents and applications in olefin metathesis I cyc1001efin polymerization area, fabrication and derivation has been presented. This volume contains the main lectures and seminars given at the NATO Advanced Study Institute on " Olefin Metathesis and Polymerization Catalysts: Synthesis, Mechanism and Utilization", held at Akcay. Babkesir. Turkey between 10th and 22nd September 1989.

Book High oxidation state Molybdenum and Tungsten Monoalkoxide Pyrrolide Alkylidenes as Catalysts for Olefin Metathesis

Download or read book High oxidation state Molybdenum and Tungsten Monoalkoxide Pyrrolide Alkylidenes as Catalysts for Olefin Metathesis written by Erik Matthew Townsend and published by . This book was released on 2014 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chapter 1 describes work toward solid-supported W olefin metathesis catalysts. Attempts to tether derivatives of the known Z-selective catalyst W(NAr)(C3H6)(pyr)(OHIPT) (Ar = 2,6- diisopropylphenyl, pyr = pyrrolide; HIPT = 2,6-bis-(2,4,6-triisopropylphenyl)phenyl) to a modified silica surface by covalent linkages are unsuccessful due to destructive interactions between W precursors and silica. W(NAr)(C3H6)(pyr)(OHIPT) and W(NAr)(CHCMe2Ph)(pyr)(OHIPT-NMe2) (HIPT-NMe 2 = 2,6-bis-(2,4,6-triisopropylphenyl)-4- dimethylaminophenyl) are adsorbed onto calcined alumina. W(NAr)(C 3H6 )(pyr)(OHIPT) is destroyed upon binding to alumina, while W(NAr)(CHCMe 2Ph)(pyr)(OHIPT-NMe 2) appears to bind through a non-destructive interaction between the dimethylamino group and an acidic surface site. The heterogeneous catalysts perform non-stereoselective metathesis of terminal olefins, and W(NAr)(CHCMe2Ph)(pyr)(OHIPT-NMe2) can be washed off the surface with polar solvent and perform solution-phase Z-selective metathesis. Chapter 2 details selective metathesis homocoupling of 1,3-dienes with Mo and W monoalkoxide pyrrolide (MAP) catalysts. A catalytically relevant vinylalkylidene complex, Mo(NAr)(CHCHCH(CH3)2)(Me2pyr)(OHMT) (HMT = 2,6-bis(2,4,6-trimethylphenyl)phenyl; Me2pyr = 2,5-dimethylpyrrolide), is isolated. A series of Mo and W MAP catalysts is synthesized and tested for activity, stereoselectivity, and chemoselectivity in 1,3-diene metathesis homocoupling. Catalysts containing the OHIPT ligand display excellent selectivity in general, and W catalysts are less active but more selective than their Mo counterparts. Chapter 3 recounts the synthesis and characterization of several heteroatom-substituted alkylidene complexes with the formula Mo(NAr)(CHER)(Me2pyr)(OTPP) (TPP = 2,3,5,6- tetraphenylphenyl; ER = OPr, N-pyrrolidinonyl, N-carbazolyl, pinacolborato, trimethylsilyl, SPh, or PPh2). Synthesis proceeds via alkylidene exchange between Mo(NAr)(CHR)(Me2pyr)(OTPP) (R = H, CMe2Ph) and a CH2CHER precursor. Each complex behaves similarly to known MAP complexes in olefin metathesis processes; the electronic identity of ER has little effect on catalytic properties. Distinctive features of alkylidene isomerism and catalyst resting state are examined. Chapter 4 contains synthetic and catalytic studies of thiolate-containing Mo and W imido alkylidene complexes. The species M(NAr)(CHCMe 2Ph)(pyr)(SHMT) (M = Mo or W), Mo(NAr)(CHCMe2Ph)(Me2pyr)(STPP), and Mo(NAr)(CHCMe2Ph)(STPP)2 are synthesized by substitution of the appropriate thiol or thiolate ligands for pyrrolide or triflate ligands in metal precursors. These complexes show similar structural and spectral characteristics to alkoxidecontaining species. The thiolate complexes and their alkoxide analogues are compared for activity and selectivity in metathesis homocoupling and ring-opening metathesis polymerization processes. In general, thiolate catalysts are slower and less selective than alkoxide catalysts.

Book Metathesis Polymerization of Olefins and Polymerization of Alkynes

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.

Book Synthesis of Molybdenum Olefin Metatheses Catalysts Through Protonation Reactions

Download or read book Synthesis of Molybdenum Olefin Metatheses Catalysts Through Protonation Reactions written by Amritanshu Sinha and published by . This book was released on 2006 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) It was observed that catalytically active species for metathesis reactions can be generated by another Mo (d2) species, Mo(NArcl)(Biphen)(H2C=CH2)(ether) (NArc, = N-2,6-C12C6H3, Biphen2 = 3,3'-di-t-butyl-5,5',6,6'-tetramethyl-1,1'-biphenyl-2,2'-diolate) that could effect the ring-opening metathesis polymerization of norbornene. A mixture of Mo(NArcl)(Biphen)(H2C=CH2)(ether) and 20 equivalents of diallylether in benzene-d6 when treated with 10 equivalents of norbornene gives 54% conversion to dihydrofuran in 10 days.

Book Advances in Organometallic Chemistry

Download or read book Advances in Organometallic Chemistry written by Pedro J. Perez and published by Elsevier. This book was released on 2023-02-28 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Organometallic Chemistry, Volume 79, the latest release in this longstanding serial, is known for its comprehensive coverage of topics in organometallic synthesis, reactions, mechanisms, homogeneous catalysis, and more. It is ideal for a wide range of researchers involved in organometallic chemistry, with this updated release including chapters on Organometallic-like reactivity of group 10 metal-heteroatom sigma bonds, Organometallic interactions between metal nanoparticles and carbon-based molecules: a surface reactivity rationale, Group VI Allenylidene Complexes, and more. Contains contributions from leading authorities in the field of organometallic chemistry Covers topics in organometallic synthesis, reactions, mechanisms, homogeneous catalysis, and more Informs and updates readers on the latest developments in the field Carefully edited to provide easy-to-read material

Book Investigations of Sterically Demanding Ligands in Molybdenum and Tungsten Monopyrrolide Monoalkoxide Catalysts for Olefin Metathesis

Download or read book Investigations of Sterically Demanding Ligands in Molybdenum and Tungsten Monopyrrolide Monoalkoxide Catalysts for Olefin Metathesis written by Laura Claire Heidkamp Gerber and published by . This book was released on 2013 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chapter 2 investigates the mechanism of the temperature-controlled polymerization of 3- methyl-3-phenylcyclopropene (MPCP) by Mo(NAr)(CHCMe 2Ph)(Pyr)(OTPP) (Ar = 2,6- diisopropylphenyl, Pyr = pyrrolide, OTPP = 2,3,5,6-tetraphenylphenoxide). Cissyndiotactic poly(MPCP) is obtained at -78 °C, while atactic poly(MPCP) is obtained at ambient temperature. The syn initiator (syn refers to the isomer in which the substituent on the alkylidene points towards the imido ligand and anti where the substituent points away) reacts with MPCP to form an anti first-insertion product at low temperatures, which continues to propagate to give cis,syndiotactic polymer. At higher temperatures, the anti alkylidenes that form initially upon reaction with MPCP rotate thermally to syn alkylidenes on a similar timescale as polymer propagation, giving rise to an irregular polymer structure. In this system cis,syndiotactic polymer is obtained through propagation of anti alkylidene species. Chapters 3 - 5 detail the synthesis and reactivity of compounds containing a 2,6- dimesitylphenylimido (NAr*) ligand in order to provide a better understanding of the role of steric hindrance in olefin metathesis catalysts. A new synthetic route to imido alkylidene complexes of Mo and W, which proceeds through mixed-imido compounds containing both NAr* and NtBu ligands, was developed to incorporate the NAr* ligand. Alkylidene formation is accomplished by the addition of 3 equivalents of pyridine*HCl to Mo(NAr*)(NBu)(CH 2CMe2Ph)2 or the addition of 1 equivalent of pyridine followed by 3 equivalents of HCl solution to W(NAr*)(N'Bu)(CH 2CMe2Ph)2 to provide M(NAr*)(CHCMe 2Ph)Cl 2(py) (py = pyridine). Monoalkoxide monochloride, bispyrrolide, and monoalkoxide monopyrrolide (MAP) compounds are isolated upon substitution of the chloride ligands. Reaction of W MAP complexes (W(NAr*)(CHCMe 2Ph)(Me2Pyr)(OR)) with ethylene allows for the isolation of unsubstituted metallacycle complexes W(N Ar*)(C 3H6)(Me 2Pyr)(OR) (R = CMe(CF 3)2, 2,6-Me2C6H3, and SiPh 3). By application of vacuum to solutions of unsubstituted metallacyclebutane species, methylidene complexes W(NAr*)(CH 2)(Me2Pyr)(OR) (R = tBu, 2,6-Me2C6H3, and SiPh 3) are isolated. Addition of one equivalent of 2,3- dicarbomethoxynorbornadiene to methylidene species allows for the observation of firstinsertion products by NMR spectroscopy. Investigations of NAr* MAP compounds as catalysts for olefin metathesis reactions show that they are active catalysts, but not E or Z selective for ring-opening metathesis polymerization the homocoupling of 1-octene or 1,3-dienes. Methylidene species W(NAr*)(CH 2)(Me2Pyr)(OR) (R = 2,6-Me 2C6H3 or SiPh3) catalyze the ring-opening metathesis or substituted norbornenes and norbornadienes with ethylene.

Book Faculties  Publications  and Doctoral Theses in Chemistry and Chemical Engineering at United States Universities

Download or read book Faculties Publications and Doctoral Theses in Chemistry and Chemical Engineering at United States Universities written by American Chemical Society. Committee on Professional Training and published by . This book was released on 1991 with total page 1646 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Synthesis of Molybdenum and Tungsten Oxo and Imido Alkylidene NHC Complexes and Their Use in Stereoselective Ring Opening Metathesis Polymerization

Download or read book Synthesis of Molybdenum and Tungsten Oxo and Imido Alkylidene NHC Complexes and Their Use in Stereoselective Ring Opening Metathesis Polymerization written by Mathis Benedikter and published by Cuvillier Verlag. This book was released on 2021-04-08 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: Im Rahmen der Dissertation wurden unterschiedliche Aspekte der Olefinmetathese mit Molybdän- und Wolframbasierten Katalysatoren untersucht. Zunächst wurde die Eignung von Molybdän Imido Alkyliden N-heterocyclischen Carben (NHC) Komplexen als Initiatoren für die ringöffnende Metathese-Polymerisation (ROMP) erforscht. Durch Einsatz von chiralen, enantiomerenreinen Norbornenderivaten als Monomer konnte gezeigt werden, dass mit diesen Komplexen selektiv trans-isotaktische Polymere hergestellt werden können. Die beobachtete Selektivität ist dabei stark abhängig von der Ligandensphäre. Des Weiteren konnte vollständig hydriertes, syndiotaktisches Polydicyclopentadien hergestellt und erstmals mittels Schmelzspinnen zu Fasern versponnen werden. Ein weiterer Schwerpunkt der Dissertation lag auf der Entwicklung neuer Katalysatoren für die Olefinmetathese. So wurde eine neue Syntheseroute zur Herstellung kationischer Wolfram Imido Alkyliden NHC Komplexen entwickelt. Durch Anpassung der Ligandensphäre konnten luftstabile kationische Molybdän und Wolfram Imido Alkyliden NHC Komplexe hergestellt werden, die hohe Produktivitäten in der Olefinmetathese von Substraten mit verschiedenen sauerstoff- und schwefelhaltigen funktionellen Gruppen zeigen. Schließlich konnte der erste Molybdän Oxo Alkyliden NHC Komplex hergestellt und charakterisiert werden.

Book High Oxidation State Molybdenum and Tungsten Imido Alkylidene and Metallacycle Chemistry

Download or read book High Oxidation State Molybdenum and Tungsten Imido Alkylidene and Metallacycle Chemistry written by W. C. Peter Tsang and published by . This book was released on 2004 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) unsubstituted tungstacyclobutane complexes (82), ethylene complexes (84), tungstacyclopentane complexes (86), and a heterochiral methylene dimer (85a). The tungstacyclopentane complexes catalyzed slow dimerization of ethylene to 1-butene. The observation of the methylene dimer provides the first direct evidence of a bimolecular decomposition pathway for methylene complexes. Chapter 3 Racemic and enantiomerically pure molybdenum alkylimido alkylidene complexes, Mo(NAd)(CHCMe2Ph)(Biphen) (19d, Ad = 1-adamantyl) and Mo(NAd)(CHCMe2Ph)[Trip]-(THF) (20d) were prepared and structurally characterized. Complex 19d was observed almost exclusively as a syn alkylidene isomer, in contrast with 20d which was observed almost exclusively as an anti-THF adduct. Complexes 19d and 20d are the only reported chiral alkylimido alkylidene complexes for enantioselective olefin metathesis reactions. Complex 19d is the first crystallographically characterized four-coordinate adamantylimido alkylidene complex in its base-free form. It offers unique reactivity and selectivity profiles in tandem AROM/RCM and AROM/CM reactions. Complex 19d is compatible with a variety of common functional groups, including boron-containing reagents. Van't Hoff analyses suggest that the bias toward syn-19d isomer is entropy-driven. Chapter 4: Solvent- and base-free molybdenum methylene complexes, Mo(NAr)(Biphen)(CH2) (114a, Ar = 2,6-i-Pr2C6H3) and Mo(NAd)(Biphen)(CH2) (114d, Ad = 1-adamantyl) ...

Book Molybdenum Oxide   Mesoporous Silica Metathesis Catalysts

Download or read book Molybdenum Oxide Mesoporous Silica Metathesis Catalysts written by Pavel Topka and published by LAP Lambert Academic Publishing. This book was released on 2013 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: Alkene metathesis attracted recently much attention, especially with the 2005 Nobel prize awarded for the development of the metathesis method in organic synthesis. Supported molybdenum oxide catalysts are widely used in industrial petrochemical processes, including metathesis (e.g. Phillips triolefin process, Shell higher olefin process). The present work discloses new type of metathesis catalysts based on molybdenum oxide supported on mesoporous silica. The key idea is to improve the activity of molybdenum oxide catalyst in this reaction utilizing high surface area and narrow pore size distribution of the support material. For the preparation of the catalysts, innovative and environmentally friendly thermal spreading method was employed. The thorough characterization of the catalysts by physicochemical techniques is described. The analysis of activity/selectivity vs. composition/structure relationships should help shed some light on this new and exciting field of heterogeneous catalysis, and should be especially useful to professionals in metathesis chemistry, or anyone else who may be considering utilizing molybdenum oxide catalysts for another catalytic reaction.

Book Alkene Metathesis in Organic Synthesis

Download or read book Alkene Metathesis in Organic Synthesis written by Alois Fuerstner and published by Springer. This book was released on 2003-07-01 with total page 231 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organometallic chemistry is a well established research area at the interface of organic and inorganic chemistry. In recent years this field has undergone a ren aissance as our understanding of organometallic structure, properties and mechanism has opened the way for the design of organometallic compounds and reactions tailored to the needs of such diverse areas as medicine, biology, materials and polymer sciences and organic synthesis. For example, in the de velopment of new catalytic processes, organometallic chemistry is helping meet the challenge to society that the economic and environmental necessities of the future pose. As this field becomes increasingly interdisciplinary, we recognize the need for critical overviews of new developments that are of broad significance. This is our goal in starting this new series Topics in Organometallic Chemistry. The scope of coverage includes a broad range of topics of pure and applied or ganometallic chemistry, where new breakthroughs are being achieved that are of significance to a larger scientific audience. Topics in Organometallic Chemistry differs from existing review series in that each volume is thematic, giving an overview of an area that has reached a stage of maturity such that coverage in a single review article is no longer possible. Furthermore, the treatment addresses a broad audience of researchers, who are not specialists in the field, starting at the graduate student level. Discussion of possible future research directions in the areas covered by the individual volumes is welcome.

Book Olefin Upgrading Catalysis by Nitrogen based Metal Complexes I

Download or read book Olefin Upgrading Catalysis by Nitrogen based Metal Complexes I written by Giuliano Giambastiani and published by Springer Science & Business Media. This book was released on 2011-04-29 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights key advances that have occurred in the field of olefin conversion in recent years. The role of homogenous transition metal catalysts which contain an imine functionality is emphasized; their potential applications in the processing and upgrade of olefins to a wide variety of commodity products of very high industrial value is also explored. On the threshold of the fiftieth anniversary of the Noble Prize to Ziegler and Natta, this book gives a critical summary of the state of the art developments in the fascinating and rapidly developing field of the olefin polymerization, oligomerization, and co-polymerization catalysis.

Book Transition Metals and Organometallics as Catalysts for Olefin Polymerization

Download or read book Transition Metals and Organometallics as Catalysts for Olefin Polymerization written by Walter Kaminsky and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 443 pages. Available in PDF, EPUB and Kindle. Book excerpt: More than 30 years after the discovery of transition metals and organometal lics as catalysts for olefin polymerization these catalysts did not have lost their fascination. Since 1953 when Karl Ziegler has discovered the catalytic polymerization of ethylene leading to plastically formable polymers which are mechanically stable up to temperatures of about 100°C, synthetic polymers and rubbers have made their way right into private houses. This discovery has been a main impetus for the fast growing production of plastics. The stereoselective poly merization of propylene and other long-chain a-olefins first detected by Giulio Natta leads to an even broadened field of applications. Another enforcing factor were the developments of Standard Oil of Indiana and Phillipps Petroleum Company who engaged in the polymerization of a-olefins supported molybdenum, cobalt and later on chromium catalysts which clearly indicates the wide variety of suitable systems. This kind of research acknowledged merit when in 1963 the Nobel prize of chemistry was awarded to Ziegler and Natta. Although to a great extent there is a technical application for these catalysts, up to now the nature of the active centres and many reaction mechanisms are not completely known.

Book Olefin Metathesis

    Book Details:
  • Author : Karol Grela
  • Publisher : John Wiley & Sons
  • Release : 2014-04-11
  • ISBN : 1118711564
  • Pages : 608 pages

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