Yavuz İmamoğlu

Metathesis polymerization of olefins and polymerization of alkynes

Part I: Metathesis Polymerization of Olefins: Romp and Admet. Ring-Opening Metathesis Polymerization by Molybdenum Imido Alkylidene Complexes R.R. Schrock. Metathesis of Low-Strain Olefins and Functionalized Olefins with New Ruthenium-Based Catalyst Systems A.F. Noels, A. Demonceau. Synthesis of Aryloxide Tungsten (VI) Complexes and Their Application in Olefin Metathesis F. Lefebvre, et al. Novel Catalysts for Addition Polymerization of Norbornene and its Derivatives K.L. Makovetsky, et al. The Use of Non-Traditional Catalysts in the ROMP of Cycloolefins K.L. Makovetsky. Correlation between Catalyst Nature and Polymer Selectivity in ROMP of Cycloolefins with WCl6-Based Catalytic Systems V. Dragutan, et al. Ring-Opening Metathesis Polymerization of Cycloolefins Using Tungsten-Tetraphenylporphyrinate Catalysts V. Dragutan, et al. Metathesis Ring-Chain Equilibrium in Cyclobutene and 1-Methylcyclobutene Systems E. Thorn- Csanyi. Olefin Cyclopropanation or Olefin Metathesis with Late Transition Metal Complexes? A.F. Noels, A. Demonceau. Initiation, Propagation and Termination of Olefin Metathesis Reactions L. Bencze, et al. Synthesis of Membrane Materials by ROMP of Norbornenes E.Sh. Finkelshtein, et al. Olefin Metathesis in Organosilicon Chemistry E.Sh. Finkelshtein. Side Chain Liquid Crystalline Polymers via ROMP. Influence of Content of Mesogenic Groups and Tacticity on the LC Behaviour M. Ungerank, et al. Optically Active Polymers via ROMP of Enantiomerically Pure Monomers F. Stelzer, et al. Synthesis of Well-Defined Graft Copolymers via Coupled Living Anionic and Living Ring Opening Metathesis Polymerisation E. Khosravi. Recent Developments in the Synthesis of Fluorinated Homopolymers and Block Copolymers via Living Ring Opening Metathesis Polymerisation E. Khosravi. Formation of Hydrocarbon and Functionalized Polymers by Acyclic Diene Metathesis (ADMET) Polymerization K.B. Wagener, P.S. Wolfe. A New Synthetic Route to Soluble Conjugated Polymers with Valuable Optical Properties P. Kraxner, E. Thorn-Csanyi. Metathesis Depolymerization Chemistry as a Means of Recycling Polymers to Telechelics and Fine Organic Chemicals K.B. Wagener, et al. Quantitative Determination of the Microstructure and Composition of Crosslinked Rubber Blends H.-D. Luginsland, E. Thorn-Csanyi. Industrial Applications of the Olefin Metathesis Reaction F. Lefebvre, J.-M. Basset. Part II: Alkyne Polymerization. Living Polymerization of Alkynes by Molybdenum Imido Alkylidene Complexes R.R. Schrock. Catalytic Transformation of Alkenes and Alkynes in the Presence of Group 6 Metal Carbonyls T. Szymaska-Buzar. Part III: Molecular Modeling and Alkene Polymerization. Derivatives of Chromocene in Ethylene Polymerisation B.R. Messere, et al. A Possible Mechanism of Polymer Formation from a,b-Unsaturated Carbonyl Compounds under the Influence of Metathesis Catalytic Systems Ch. Jossifov.

Electrochemically generated catalyst system with increased specificity and efficiency for olefin metathesis

Abstract A facile route for the electrochemical generation of an olefin metathesis catalyst from methylene chloride solution of WCl 6 was described. It was found that reductive, oxidative and pulse electrolysis produced the same intermediate. This electrolysis intermediate incorporates olefin into its structure possibly forming a metal–olefin complex, which decomposes into catalytically active metal carbene type species. ESCA, NMR and ESR methods were used to elucidate the structure of the catalyst system. The catalyst was applied in the metathesis of 1-octene and 2-octene without any need for a co-catalyst. Highly specific products with high yields were obtained.

Recent Advances in the Applications of Electrochemically Generated Molybdenum and Tungsten-Based Catalysts for the Olefins Metathesis

Catalytic olefin metathesis has quickly emerged as one of the most often-used transformations in modern chemical synthesis. One class of catalysts that has led the way to this significant development are the electrochemically produced tungsten- and molybdenum-based species. In this review, some of the discovery, developments and applications of electrochemically generated tungsten- and molybdenum-based metathesis catalysts are outlined.

Study of the Stability and Activity of Electrochemically Produced Tungsten-Based Metathesis Catalyst with Symmetrical Alkenes

The olefin metathesis reaction has been carried out with many olefins of different types over various kinds of both homogeneous and heteregeneous catalysts [1, 2, 3]. The activity of a particular catalyst system depends on a number of factors, such as proportions of the components, the order in which the components are mixed, pretreatment procedures and reaction time [4]. Optimization of a given catalyst system by adjustment of the various parameters inturn can be quite a lengthy procedure.

ADMET Polymerization Activities of Electrochemically Reduced W-Based Active Species for Ge- and Sn-Containing Dienes

In the last 20 years metal atom-containing polymers have become important classes of polymers [1]. Properties like high thermic stability, electric, and photo conductometry make them very interesting for producing films, fibers, and coating [2]. Many of these compounds can be synthesized by conventional methods [3]. For producing metal-containing polymers anionic, cationic, and radicalic polymerizations were used [4–6]. Metal-containing polymers were also synthesized via acyclic diene metathesis (ADMET) polymerization that is facilitated by Schrock’s molybdenum alkylidene, or Grubbs’ ruthenium carbene catalyst [7–9]. In 1979, Gilet and coworkers succeeded in synthesizing metathetically active species from electrochemical reduction of WCl6 and MoCl5 [10,11]. In the light of these works, we have showed that electrochemically generated tungsten-based active species (WCl6-e–Al–CH2Cl2) catalyzes various metathesis-related reactions [12–16].

Acyclic Diene Metathesis (ADMET) Polymerization of Bis(4-pentenyl) dimethylstannane and Bis(4-pentenyl) diphenylstannane with an Electrochemically Activated Catalyst System

The microstructure and thermal analysis of two polycarbostannanes, obtained by acyclic diene metathesis (ADMET) polymerization in the presence of an electrochemically reduced tungsten-based catalyst system, were investigated in this study by NMR, DSC, and TGA techniques.

A Study on the Reactivity of WCl6–e––Al–CH2Cl2 with the Silicon-Containing Dienes

Although until the late 1980s very little information on effective metathesis conversion of organosilicon compounds had been reported, the use of molybdenum (Schrock) catalyst and ruthenium (Grubbs) carbene complexes as catalysts tolerating functional groups in substrates, have opened new synthetic opportunities in organosilicon chemistry. Silicon containing dienes undergo two types of metathetical transformation.

Application of Uniform Macroporous Polystyrene Particles as Support in W(CO) 6 /CC14/hv Photocatalytic Olefin Metathesis System

Olefin metathesis has made a great impact in synthetic organic chemistry as a result of the preparation of many new polymers and valuable low molecular compounds. In this reactions, active species are metal carbenes that they can be generated in situ (classical systems) or added as well defined single components, which provide potential for enlarged application of metathesis in various fields[1]. Immobilization of the metathesis catalysts on solid supports will facilitate the work up and make the metahesis reactions more attractive for both pratical and industrial applications.

Acyclic Diene Metathesis (ADMET) Polymerization by Electrochemically Generated Tungsten-Based Active Catalyst System: Optimization of Reaction Conditions

Dienes can undergo olefin metathesis reactions of two types: (i) intermolecular, and (ii) intramolecular. Intramolecular metathesis (RCM) reactions occur with great readiness henever the product is a 6-membered ring. They are also often favoured for the production of 5-, 7-, and 8-membered rings, depending on the nature, number and location of any substituents. Intermolecular metathesis reactions lead eventually to high polymers and proceed very cleanly when initiated by metal carbene complexes; these are known as ADMET (acyclic diene metathesis) polymerizations (Figure 1). This class of polymerization reactions has been well established and comprehensively studied by Wagener and his group [1–6]. ADMET polymerization has been also a convenient route to linear polymers containing inorganic elements and functional groups for the preparation of new materials [7].

Metathetical Degradation of Sulfur Vulcanized Polybutadiene By W(CO)6 /CCI4 /hv

In the present work, the photocatalytic metathesis degradation of sulfur-vulcanized polybutadiene were studied. The yields in the synthesis of organic compounds from elastomeric polymers and also from vulcanized polymer wastes were explored. Effects of polymer, olefine and catalyst concentrations, irradiation period and temperature were determined. At optimum conditions determined for polybutadiene, the effects of sulfur content, vulcanization time and temperature on product formation were then investigated for vulcanized polybutadienes.