Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 58 for “"Transition metal catalysts"”.
-
Transformation of biomass carbohydrates by transition metal catalysts
… acid has now been produced in high yields with a metal salt. The difference between maximizing production for HMF or levulinic acid from the same catalyst relies on the control of the reaction conditions. By using microwave irradiation, improved collisions and stabilized transition states allow …
-
NEW TRANSITION METAL CATALYSTS FOR CARBON-CARBON BOND FORMATION
… they enable have been the driving force of organometallic chemistry for the past decades. Since their inception, organometallic complexes have been applied to the formation of carbon-carbon bonds both as reagents and catalysts. Ligands and complexes tailored for a particular reaction have …
-
Mechanistic insights into the direct synthesis of H2O2 on transition metal catalysts
… favored over direct synthesis to H2O2 on most transition metal catalysts, and so significant research has been directed towards improving catalyst selectivity towards H2O2 through various methods. Despite significant research, the mechanism of this reaction, and the reasons for the importance …
-
Development of new late transition metal catalysts for the oligomerisation of ethene
… and nickel and palladium a-diimine catalysts for the polymerisation and oligomerisation of l-alkenes has stimulated interest in the use of late transition metals as catalysts for these processes.
-
Early transition metal catalysts for the living polymerization of olefins and alkynes
Zirconium and Hafnium Ziegler-Natta catalysts containing the [(2,6- C12C6H3NCH2CH2)2NMe]2- ([ArciN2NMe]2') ligand were prepared and employed in the polymerization of 1-hexene. Hafnium Ziegler-Natta catalysts containing the [(2,6- X2C6H3NHCH2)2C(CH3)(2-C5H4N)] ([Arx2NPy]2-) (X = Cl or F) ligand were …
-
Spectroscopic and kinetic evidence for origins of selective bond activation over transition metal catalysts
Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2024-05-01
-
Development of new transition metal catalysts for C-N bond formation and continuous flow processes for C-F bond formation
… accessing N-aryl a-branched tertiary amines, new catalysts have been designed to suppress undesired side reactions often encountered when these amine nucleophiles are used. These advances enabled the arylation of a wide array of sterically encumbered amines, highlighting the importance of rational …
-
Production of Single-Walled Carbon Nanotubes by Chemical Vapor Deposition: Design and Scale Up
… at various temperatures and gas flow rates with transition metal catalysts. Two processes to produce 10,000 tons per year of single-walled carbon nanotubes are proposed. Process simulations and cost analyses are included in the evaluation of each process design.
-
Synthesis and Characterization of New Platinum Group Metal Cluster Complexes Containing Tin and Germanium Ligands
… to enhance the activity and selectivity of transition metal catalysts. Platinum group metal derived bimetallic (platinum group metal-tin) clusters are used as precursors to nanoscale catalysts which are proven to be more effective than their monometallic counterparts. Ruthenium is a platinum …
-
Synthesis, characterization, and catalytic reactivity of first-row transition metal CCC pincer complexes
… and 90% of newly developed processes utilize catalysts. Understanding how to improve and create new catalysts is therefore essential to developing new products as well as greener and more efficient processes. One way to improve the environmental impact of these reactions is to move away from …
-
Exploring Photocatalytic and Electrocatalytic Reduction of CO2 with Re(I) and Zn(II) Complexes and Attempts to Employ a Novel Carbene Ligand to this Endeavor
… of CO2. Re(I) integrated photosensitizers and catalysts, synthesized from commercially available ligands, are introduced with the selective CO2 reduction of formic acid, making for a unique class of Re(I) catalysts typically selective for CO as a reduction product. Furthermore, synthesized …
-
The development of a model for high pressure propene oligomerisation over H-ZSM-5
… revises the characteristics and applications of catalysts which have been shown to be active for oligomerisation. This is further split into acid catalysts, heterogeneous nickel catalysts, other transition metal catalysts and finally homogeneous metal catalysts. The next section covers the …
-
Metal-ligand cooperativity in first row transition metals: hydrosilylation catalysis and mechanistic insights
The utility of transition metal catalysts has greatly expanded the scope of organic reactions. Historically, homogenous catalysis is dominated by platinum group metals (PGMs) due to their relative high activity and stability to air when compared to the 1st row counterparts of PGMs. However, 1st row …
-
Stereo–Chemical Control of Organic Reactions in the Interlamellar Region of Cation–Exchanged Clay Minerals
… can be generated by thermal, photochemical and transition metal catalysed processes from diazoalkanes. The carbene intermediates are very reactive and can add across double bonds to give 3-membered rings (cyclopropanes), insert into OH bonds to give esters and insert into neighbouring C-H bonds …
-
Synthesis of Chiral Benzimidazolylidenes from 1,10-Phenathrolines and 1,10-Phenathroline-2,9-dione /
… focus of much interest as ancillary ligands for transition metal catalysts in recent years. Their structural variability and strong cy-donation properties have led to the preparation of demonstrably useful organometallic catalysts. Among the three general structural types of NHCs …
-
Reaction mechanisms for catalytic partial oxidation systems : application to ethylene epoxidation
… and chelating coordination structures on transition metal catalysts. The UBI-QEP theory for diatomics has been extended for polyatomic adsorbates with empirical modifications to the theory.
-
Trichloroacetimidates as Alkylating Reagents in C-N Bond Formation and Synthesis of Aminosteroid and Quinoline Inhibitors of Src Homology 2 Domain-Containing Inositol Phosphatase (SHIP)
… thermally or through the use of Lewis acid or transition metal catalysts. Recently, the direct substitution of trichloroacetimidates using nitrogen nucleophiles has been accomplished utilizing transition metal catalysts, which indicates that trichloroacetimidates may be suitable alkylation …
-
Exploring Simple Catalyst for Transfer Hydrogenation of Ketones and Photocatalytic Hydrogen Production Using Homogeneous Metal Complexes
… to obtain valuable products including alcohols. Transition metal catalysts based on precious metals, such as Ru, Rh and Ir, are typically employed for this process. This thesis starts with a study on the potential of an Fe based complex carrying a PNP ligand (2,6-{Ph2PNH}2(NC5H3)) to function as …
-
I. The Catalytic Oxidation of Olefins by a Cobalt Complex. Ii. The Thermodynamics of Base Binding to a Cobalt Complex (Cosmdpt)
… but also commercially. In many cases transition metal catalysts are used to improve the rate and/or selectivity of such oxidations. Many homogeneous oxidations catalyzed by transition metal complexes, especially those containing first row transition metals, proceed by autoxidation. …
Page 1 of 3