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1	Synthesis and Characterization of Cyclopentadienyl Dicarbonyldiphenylphosphinopropyliron for Migratory Insertion Polymerization Liu, Yibo January 2013 (has links) Metal-containing polymers (MCPs) are emerging as a class of interesting materials with promising properties and functions. Although many techniques are available for their synthesis, the range of main-chain MCPs available for material applications is limited. Most well-defined main-chain MCP syntheses rely only on the ring-opening polymerization (ROP) of metallocene monomers, thereby new synthetic approaches for novel MCPs are in high demand. In this study a new polymerization technique, migratory insertion polymerization (MIP), was explored and used to produce novel types of MCPs with asymmetric iron repeat-units connected by phosphine-iron (Ph2P-Fe) and iron-acyl (Fe-CO) bonds in the backbone. This research work involved the synthesis, characterization and polymerization of cyclopentadienyl(dicarbonyl)(diphenylphosphinopropyl)iron (FpP). FpP consists of an Fp functional group capable of undergoing a migratory insertion reaction (MIR) and a phosphine group to assist the MIR. FpP was prepared via the reaction between cyclopentadienyl dicarbonyl iron metalate (Fp anion) and (3-chloropropyl)diphenylphosphine, and was characterized using Fourier transform infrared (FTIR), 1H NMR, 31P NMR, 13C NMR, and ultraviolet-visible (UV-Vis) spectroscopies. The molecules undergo intramolecular cyclization reactions at low concentrations in organic solvents, while polymerization occurs in bulk at 70°C, leading to polymers with number-average molecular weights (Mn) up to 12,000 g/mol and narrow molecular weight distributions (PDI=1.08-1.33). These polymers are soluble in a wide range of organic solvents and have a Tg of 100°C. Metal-containing polymers Migratory insertion polymerization Chemistry
2	Synthesis and Characterization of Cyclopentadienyl Dicarbonyldiphenylphosphinopropyliron for Migratory Insertion Polymerization Liu, Yibo January 2013 (has links) Metal-containing polymers (MCPs) are emerging as a class of interesting materials with promising properties and functions. Although many techniques are available for their synthesis, the range of main-chain MCPs available for material applications is limited. Most well-defined main-chain MCP syntheses rely only on the ring-opening polymerization (ROP) of metallocene monomers, thereby new synthetic approaches for novel MCPs are in high demand. In this study a new polymerization technique, migratory insertion polymerization (MIP), was explored and used to produce novel types of MCPs with asymmetric iron repeat-units connected by phosphine-iron (Ph2P-Fe) and iron-acyl (Fe-CO) bonds in the backbone. This research work involved the synthesis, characterization and polymerization of cyclopentadienyl(dicarbonyl)(diphenylphosphinopropyl)iron (FpP). FpP consists of an Fp functional group capable of undergoing a migratory insertion reaction (MIR) and a phosphine group to assist the MIR. FpP was prepared via the reaction between cyclopentadienyl dicarbonyl iron metalate (Fp anion) and (3-chloropropyl)diphenylphosphine, and was characterized using Fourier transform infrared (FTIR), 1H NMR, 31P NMR, 13C NMR, and ultraviolet-visible (UV-Vis) spectroscopies. The molecules undergo intramolecular cyclization reactions at low concentrations in organic solvents, while polymerization occurs in bulk at 70°C, leading to polymers with number-average molecular weights (Mn) up to 12,000 g/mol and narrow molecular weight distributions (PDI=1.08-1.33). These polymers are soluble in a wide range of organic solvents and have a Tg of 100°C. Metal-containing polymers Migratory insertion polymerization Chemistry
3	Mechanism of the Heck reaction: nature of oxidative addition and migratory insertion Evans, Anthony Steven 15 November 2004 (has links) The mechanism of carbon coupling reactions is traditionally represented in a very broad schematic. This thesis seeks to explore the mechanism of these reactions by focusing on Heck olefination. The Heck reaction has become a powerful tool in synthetic labs but the mechanism of this reaction has remained a topic of debate since the reaction's discovery. The catalytic cycle that has come to be accepted, while accurate in its own right, is not nearly as detailed as the complexity of the various stages of the Heck reaction suggest it should be. This study seeks to elucidate the nature of the oxidative addition of aryl halide to a palladium catalyst using a ligand that has been shown to have high activity in facilitating oxidative addition of aryl chlorides and bromides in other coupling reactions. This information is then compared to other studies in the field so that conclusions can be drawn about the oxidative addition. Also, selectivity studies seek to determine the nature of the migratory insertion of an olefin into the Pd-Ar bond. Again, comparison of results obtained in this study are compared to previous results so that a more definitive conclusion can be drawn about the oxidative addition. Heck reaction palladium coupling oxidative addition migratory insertion
4	Mechanism of the Heck reaction: nature of oxidative addition and alkene insertion Evans, Anthony Steven 15 November 2004 (has links) The mechanism of carbon coupling reactions is traditionally represented in a very broad schematic. This thesis seeks to explore the mechanism of these reactions by focusing on Heck olefination. The Heck reaction has become a powerful tool in synthetic labs but the mechanism of this reaction has remained a topic of debate since the reaction's discovery. The catalytic cycle that has come to be accepted, while accurate in its own right, is not nearly as detailed as the complexity of the various stages of the Heck reaction suggest it should be. This study seeks to elucidate the nature of the oxidative addition of aryl halide to a palladium catalyst using a ligand that has been shown to have high activity in facilitating oxidative addition of aryl chlorides and bromides in other coupling reactions. This information is then compared to other studies in the field so that conclusions can be drawn about the oxidative addition. Also, selectivity studies seek to determine the nature of the migratory insertion of an olefin into the Pd-Ar bond. Again, comparison of results obtained in this study are compared to previous results so that a more definitive conclusion can be drawn about the oxidative addition. Heck reaction palladium coupling oxidative addition migratory insertion
5	Migration and decarbonylation reactions of group 6 organometallic complexes using solvent-free procedures Budhai, Asheena 15 August 2008 (has links) Abstract will not load on to DSpace decarbonylation reactions drifts solvent-free steric effects electronic effects migratory-insertion reactions
6	Complexes organométalliques d'or(III) et de cuivre(III) et leur réactivité vis-à-vis des substrats π / Gold(III) and Copper(III) Organometallic Complexes and their Reactivity toward π-substrates Blons, Charlie 18 December 2018 (has links) Cette thèse porte sur la synthèse de composés d'Au(III) et de Cu(III) ainsi que sur l'étude de leur stabilité et de leur réactivité vis-à-vis de substrats p. Une approche conjointe expérimentale et théorique a été exploitée afin d'accéder à des complexes capables d'induire des processus d'insertion migratoire. Le premier chapitre aborde de manière globale la chimie organométallique de l'or et du cuivre sur le plan bibliographique. L'importance du degré d'oxydation +III est mis en évidence par la description des principaux exemples ayant contribué à la compréhension des processus associés à l'accès et la réactivité des complexes d'Au(III) et de Cu(III). Le second chapitre traite de la synthèse de deux complexes p-arènes d'Au(III) par insertion migratoire d'oléfines dans la liaison Au-C(sp)2 d'un composé (P,C) cyclométallé. Les interactions entre les systèmes aromatiques et l'or ont été mises en évidence par RMN, DFT et DRX pour un des complexes. Sur la base de cette réactivité, un processus d'arylation directe de l'éthylène a été mis en évidence. Le chapitre trois a pour objet la mise au point d'une réaction d'hydroarylation intermoléculaire d'alcynes catalysée par des complexes de type [(P,C)Au(III)(OAcF)2]. Ces derniers se sont avérés très actifs et robustes en présence d'acide trifluoroacétique. La réaction a pu être généralisée à un large panel de substrats et une étude comparative, notamment avec des complexes (N,C) cyclométallés, a mis en évidence la supériorité des complexes (P,C) pour l'hydroarylation des alcynes. Le quatrième chapitre expose la stratégie envisagée pour le développer d'un processus d'oligomérisation de l'éthylène catalysé par le cuivre. Une approche prédictive basée sur les calculs DFT a permis de mettre en évidence des insertions migratoires plus aisées dans les liaisons Cu(III)-C que dans les Cu(I)-C. Deux stratégies d'accès aux complexes de Cu(III) par addition oxydante de liaisons C-I sur des précurseurs de Cu(I) ont été évaluées théoriquement. Les calculs les plus favorables ont orienté le choix des modèles de ligands envisagés dans les chapitres cinq et six. Le cinquième chapitre aborde l'étude expérimentale associée à la première stratégie d'accès au Cu(III) : l'addition oxydante intramoléculaire dirigée par des ligands naphthylphosphine et naphthylamine peri-iodées. [...] / The present work deals with the synthesis of Au(III) and Cu(III) compounds and the study of their stability and reactivity toward p substrates. An experimental and theoretical approach has been used in order to access complexes capable of undergoing migratory insertion processes. The first chapter delivers a bibliographic overview of the organometallic chemistry of gold and copper. The importance of the high oxidation state +III is highlighted by the description of important examples having contributed to the understanding of processes associated to the access and reactivity of Au(III) and Cu(III) complexes. The second chapter describes the synthesis of two p-arene Au(III) complexes by migratory insertion of olefins in the Au-C(sp)2 bond of a (P,C) cyclometallated complex. Interactions between the metallic center and the aromatic systems have been characterized by NMR, DFT and XRD for one of the complexes. Based on this insertion reactivity, a process of direct arylation of ethylene has been evidenced. The third chapter concerns the development of an intermolecular hydroarylation of alkynes process, catalyzed by [(P,C)Au(III)(OAcF)2] complexes. These have shown great activity and robustness in presence of trifluoroacetic acid. The reaction has been generalized to a broad substrate scope and a comparative study has been carried on, especially with (N,C) cyclometallated complexes, showing the superiority of (P,C) complexes for the hydroarylation of alkynes. The fourth chapter presents the envisioned strategy to develop a copper-catalyzed oligomerization of ethylene process. A predictive approach based on DFT calculations permitted to evidence easier migratory insertions in the Cu(III)-C bond than in the Cu(I)-C bond. Two strategies for the access to Cu(III) species have been theoretically evaluated. The most favourable calculations have oriented the choice of ligand models used in chapters five and six. The fifth chapter deals with the experimental study related to the first strategy of access to Cu(III) species: the directed intramolecular oxidative addition by peri-iodo napthylphosphine and naphthylamine ligands. [...] Or(III) Insertion migratoire Complexe π Catalyse Hydroarylation Cu(III) Addition oxydante Couplages Gold(III) Migratory insertion Π-complex Catalysis Hydroarylation Copper(III) Oxidative addition Couplings
7	Investigations into cyclopropanation and ethylene polymerization via salicylaldiminato copper (II) complexes Boyd, Ramon Cornell 23 January 2007 Two distinct overall research objectives are in this Masters thesis. Very little relates the two chapters apart from the ligands. The first chapter addresses diastereoselective homogeneous copper catalyzed cyclopropanation reactions. Cyclopropanation of styrene and ethyl diazoacetate (EDA) is a standard test reaction for homogeneous catalysts. Sterically bulky salicylaldimine (SAL) ligands should select for the ethyl trans-2-phenylcyclopropanecarboxylate diastereomer. Steric bulk poorly influences trans:cis ratios. Salicylaldiminine ligands do not posses the correct symmetry to affect diastereoselectivity. The SAL ligand belongs to the Cs point group in the solid state. Other ligand motifs are more effective at altering the trans:cis ratios. The second chapter addresses the general route toward successful copper(II) ethylene polymerization catalysts. Catalytic activity of the copper(II) complexes is very low. Polymer chain growth from a copper catalyst is very unlikely. Copper-carbon bonds decompose by homolytic cleavage or C-H activation. Copper-alkyls and aryls readily decompose into brown colored oils and salts with different colors. Ligand transfer to trimethylaluminum (TMA) appears to explain low yield ethylene polymerization. bulky migratory insertion mechanism coordination/insertion methodology d-block metal late transition metal phenolic ring coordination number ketimine precatalysts ketimine nitrogen bis(salicylaldiminato)copper(II) ratio cyclopropane steric bulk salicylaldiminato TMA salt trimethylaluminum aryl oil alkyl copper-aryls copper-alkyls C-H activation homolytic homolytic cleavage copper(II) polymerization ethylene cis trans symmetry diastereomer salicylaldimine SAL EDA ethyl diazoacetate styrene cyclopropanation copper diastereoselective steric protection stable CH(SiMe3)2 intermediate catalytic activity associated TMA free TMA vacant coordination site hydrolysis Lewis acid halogen anionic anionic ligand donor ligand monodentate anionic ligand aluminum(III) monodentate polymer chain polymer chain aluminum-carbon bond bulky SAL ligand open coordination site first row transition metal PE paramagnetic high molecular weight polyethylene alkylate methylaluminoxane MAO anionic ligands arylate aluminum carbon aluminum carbon bond beta-hydrogen elimination beta hydrogen elimination Aufbau reaction Aufbau neutral dialkyl aluminum aluminum-alkyl aluminum alkyl copper(0)
8	Investigations into cyclopropanation and ethylene polymerization via salicylaldiminato copper (II) complexes Boyd, Ramon Cornell 23 January 2007 (has links) Two distinct overall research objectives are in this Masters thesis. Very little relates the two chapters apart from the ligands. The first chapter addresses diastereoselective homogeneous copper catalyzed cyclopropanation reactions. Cyclopropanation of styrene and ethyl diazoacetate (EDA) is a standard test reaction for homogeneous catalysts. Sterically bulky salicylaldimine (SAL) ligands should select for the ethyl trans-2-phenylcyclopropanecarboxylate diastereomer. Steric bulk poorly influences trans:cis ratios. Salicylaldiminine ligands do not posses the correct symmetry to affect diastereoselectivity. The SAL ligand belongs to the Cs point group in the solid state. Other ligand motifs are more effective at altering the trans:cis ratios. The second chapter addresses the general route toward successful copper(II) ethylene polymerization catalysts. Catalytic activity of the copper(II) complexes is very low. Polymer chain growth from a copper catalyst is very unlikely. Copper-carbon bonds decompose by homolytic cleavage or C-H activation. Copper-alkyls and aryls readily decompose into brown colored oils and salts with different colors. Ligand transfer to trimethylaluminum (TMA) appears to explain low yield ethylene polymerization. bulky migratory insertion mechanism coordination/insertion methodology d-block metal late transition metal phenolic ring coordination number ketimine precatalysts ketimine nitrogen bis(salicylaldiminato)copper(II) ratio cyclopropane steric bulk salicylaldiminato TMA salt trimethylaluminum aryl oil alkyl copper-aryls copper-alkyls C-H activation homolytic homolytic cleavage copper(II) polymerization ethylene cis trans symmetry diastereomer salicylaldimine SAL EDA ethyl diazoacetate styrene cyclopropanation copper diastereoselective steric protection stable CH(SiMe3)2 intermediate catalytic activity associated TMA free TMA vacant coordination site hydrolysis Lewis acid halogen anionic anionic ligand donor ligand monodentate anionic ligand aluminum(III) monodentate polymer chain polymer chain aluminum-carbon bond bulky SAL ligand open coordination site first row transition metal PE paramagnetic high molecular weight polyethylene alkylate methylaluminoxane MAO anionic ligands arylate aluminum carbon aluminum carbon bond beta-hydrogen elimination beta hydrogen elimination Aufbau reaction Aufbau neutral dialkyl aluminum aluminum-alkyl aluminum alkyl copper(0)

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