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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The synthesis of the cyclometallated palladium complexes and their applications in olefin oligomerization and in phenylacetylene oligomerization/polymerization.

Mungwe, Nothando Wandile. January 2007 (has links)
<p><font face="TimesNewRomanPSMT"> <p align="left">This thesis reports the synthesis of the imine ligands from Schiff base condensation reaction of aldehyde derivatives and equimolar quantities of aniline derivatives. The imine ligands spectrometry.</p> </font></p>
2

The synthesis of the cyclometallated palladium complexes and their applications in olefin oligomerization and in phenylacetylene oligomerization/polymerization.

Mungwe, Nothando Wandile. January 2007 (has links)
<p><font face="TimesNewRomanPSMT"> <p align="left">This thesis reports the synthesis of the imine ligands from Schiff base condensation reaction of aldehyde derivatives and equimolar quantities of aniline derivatives. The imine ligands spectrometry.</p> </font></p>
3

The synthesis of the cyclometallated palladium complexes and their applications in olefin oligomerization and in phenylacetylene oligomerization/polymerization

Mungwe, Nothando Wandile January 2007 (has links)
Magister Scientiae - MSc / This thesis reports the synthesis of the imine ligands from Schiff base condensation reaction of aldehyde derivatives and equimolar quantities of aniline derivatives. The imine ligands spectrometry.
4

Rh-catalyzed asymmetric C-H bond activation by chiral primary amine

Taleb Sereshki, Farzaneh 03 February 2017 (has links)
Developing asymmetric C-H bond activation methods in order to achieve enantiopure products is crucial for the advancement of the field and for the production of novel chiral compounds. Therefore, we tried to develop this area of organic chemistry by presenting metal catalyzed stereoselective C-H bond activation utilizing chelation-assisted tools. The first section of this study involves Rh(I) catalyzed asymmetric C-H bond activation of a series of ketones via an intermolecular procedure. By this method, we examine ortho-alkylation of aromatic ketones and β-functionalization of α-β unsaturated ketones with a series of prochiral olefins. In the second section, we present an efficient three steps method for stereoselective intramolecular C-H bond activation of indol-3-carboxaldehyde with tethered prochiral olefins. The catalytic system in both methods involves a joint chiral primary amine and Rh(I) catalyst. Chiral primary amines can serve to induce enantioselectivity as well as acting as a useful directing group which has shown appropriate coordination to the transition metal catalyst, providing high regioselectivity. / February 2017
5

Synthesis and Mechanistic Studies on the Reaction of N-phenylpyridin-2-Amine Palladacycle with Aryltrifluoroboratess to 9-(pryidin-2yl)-9H-carbazole

Li, Ya-Ming 09 August 2010 (has links)
An effiecient stoichiometric amount system has been developed for the synthesis of N-phenylpyridin-2-amine Palladacycle, and then reation with aryl trifluoroborate to 9-(pyridine-2-yl)-9H-carbazoles by C-H bond activation/ C-C bond formation and C-N bond formation. The subsitutent effect of the aryl trifluoroborate with N-phenylpyridin-2-amine Palladacycle intermediate was observed. Mechanistic studies of C-H bond cleavaged, including trapping of reaction intermediates and kinetic isotope effect experiments, are also presented.
6

Sulfonyl Chlorides as Versatile Reagents for Chelate-assisted C–H Bond Functionalizations

Dimitrijevic, Elena 14 January 2010 (has links)
Despite the great abundance of C–H bonds in readily available starting materials, their use in synthesis of functionalized molecules has been hampered by the high bond strengths, rendering them inert to common organic reagents. However, recent progress in the field has addressed this issue, enabling selective C–H bond functionalizations to be performed using catalytic transition metal mediated processes. Herein, the use of sulfonyl chlorides as versatile reagents for C–H bond functionalizations is reported. Using chelation assistance, the regioselective conversion of C–H bonds to either C–S, C–Cl or C–C bonds was achieved. The methodology development, substrate scope determination and mechanistic investigations will be discussed.
7

Sulfonyl Chlorides as Versatile Reagents for Chelate-assisted C–H Bond Functionalizations

Dimitrijevic, Elena 14 January 2010 (has links)
Despite the great abundance of C–H bonds in readily available starting materials, their use in synthesis of functionalized molecules has been hampered by the high bond strengths, rendering them inert to common organic reagents. However, recent progress in the field has addressed this issue, enabling selective C–H bond functionalizations to be performed using catalytic transition metal mediated processes. Herein, the use of sulfonyl chlorides as versatile reagents for C–H bond functionalizations is reported. Using chelation assistance, the regioselective conversion of C–H bonds to either C–S, C–Cl or C–C bonds was achieved. The methodology development, substrate scope determination and mechanistic investigations will be discussed.
8

Investigating rhodium-catalysed hydroacylation and carbon-carbon bond activation

Coxon, Thomas January 2017 (has links)
The work described in this thesis documents the development of new rhodium(I)-catalysed methodologies within two areas of research. The first examines the use of carbonyls as chelating groups in hydroacylation to produce synthetically valuable ketones and enones. The second area explores new carbon-carbon bond activation methodologies. Chapter 1 presents a literature review of the historical development of rhodium-catalysed hydroacylation, with a focus on chelating groups that can currently be used to suppress decarbonylation. A brief review of methodologies that avoid the requirement for a tether is also included. Chapter 2 describes the development of a novel hydroacylation methodology employing carbonyl-based functional groups as tethers on aldehyde substrates. The chapter begins with the optimisation studies for the hydroacylation of &beta;-formyl amides with terminal and internal alkynes, allenes and terminal alkenes, and subsequently explores the substrate scope for each case. The chapter then outlines the investigations undertaken with 1,4-dicarbonyl and 1,5-dicarbonyl systems, N-formyl amides, &beta;-formyl esters and finally &beta;-formyl ketones. A detailed description of the routes undertaken to synthesise each starting material is also presented. Chapter 3 presents a short review surveying the key milestones in the development of carbon-carbon activation methodologies. The chapter begins with a theoretical comparison to carbon-hydrogen activation and a discussion of the unique challenges that are faced. An overview of the major strategies employed to enact these processes is subsequently presented for both strained and unstrained substrates. Chapter 4 outlines the attempts undertaken to develop a novel carbon-carbon bond activation methodology. The work evaluates sulfur-, nitrogen- and alkene-based chelating groups, known to be successful in hydroacylation, in analogous ketone substrates. Chapter 5 discusses the conclusions from this work and the potential for further work. Chapter 6 presents the experimental procedures and data.
9

Development of New Cobalt Pincer Complexes for Catalytic Reduction Reactions

Li, Yingze 18 October 2019 (has links)
No description available.
10

Synthesis of N-(2-pyridinyl)-carbazoles and Their Iridium (III) Complexes

Shen, Wei-ting 30 July 2010 (has links)
N-phenylpyridin-2-amine , treated with stochiometric amount of palladium(II) acetate in dichloromethane at 65-70¢J for 4 h, to give high yield palladacycle 53. The reaction of palladacycle 53 with potassium aryltrifluoroborates in 1,4-dioxane at 140¢J for 24 h, could give a variety of N-(2-pyridinyl)carbazoles 55a-55m via sequential C-H bond activation. Carbazole derivative 55a reacted with irdium chloride gave iridium dimer, which followed by addition of picolinic acid via ligand exchange will form iridium complexes, which can further be utilized as OLEDs materials.

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