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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.
71

Ruthenium- and Cobalt-Catalyzed Chelation-Assisted C-H Functionalizations

Li, Jie (Jack) 03 July 2015 (has links)
No description available.
72

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.
73

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.
74

Part A: Palladium-Catalyzed C–H Bond Functionalization Part B: Studies Toward the Synthesis of Ginkgolide C using Gold(I) Catalysis

Lapointe, David 26 January 2012 (has links)
The field of metal-catalyzed C–H bond functionalizations is an incredibly vibrant and spans beyond the formations of biaryl motifs. The introduction chapter will cover the mechanistic aspects of the C–H bond functionalization with metal-carboxylate complexes. The mechanistic facets of this reaction will be the main conducting line between the different sections and chapters of the first part of this thesis. In the second chapter, will be described additives that can readily promoted C–H bond arylation of poorly reactive substrates. More specifically, we will revisit the intramolecular direct arylation reaction we will demonstrate the effect of pivalic acid as a co-catalyst by developing milder reaction conditions. In the third chapter we be described experimental and computational studies which suggested that the a single pathway might be involved in the palladium-catalyzed C–H bond functionalization of a wide range of (hetero)arene. Following this we will describe a general set of conditions for the direct arylation of wide range of heteroarenes. Also, we will present two different strategies to selectively and predictably arylate substrates containing multiple functionalizable C–H bonds. In the fourth chapter will be presented our efforts toward the development of new C–H bond functionalization methods in which we could apply our knowledge on the C–H bond cleavage and apply it to the formation of new scaffolds. The development of two new palladium-catalyzed methods were also described. In the fifth chapter, our effort toward the development of ligands to specifically promoted C–H bond cleavage will be presented. In the sixth chapter will be presented the latest results on the study of the mechanism of the C–H bond cleavage combining experimental and computational studies. In part B of this thesis will be presented our strategy toward the total synthesis of ginkgolide C that included two gold(I)-catalyzed reactions as key steps in the preparation of the spiro[4.4]nonane core of this natural product. The first studies on the feasibility of the key steps of the synthesis will be described.
75

Pastors, be still and know that I am God! a discussion of the applicability of the doctrine of the providential care of God for the outlook of evangelical pastors dealing with difficulties in ministry /

Moore, Bryan E., January 1998 (has links)
Thesis (D. Min.)--Gordon-Conwell Theological Seminary, South Hamilton, Mass., 1998. / Abstract and vita. Includes bibliographical references (leaves 198-202).
76

The impact of prayer on the ministries of D.L. Moody, C.H. Spurgeon, and Billy Graham : a descriptive study /

Baker, Rodney, January 1999 (has links)
Thesis (D. Min.)--Liberty Baptist Theological Seminary, 1999. / Includes bibliographical references.
77

Late-Stage Peptide Functionalization by Ruthenium-Catalyzed C H Arylations and Alkylations

Schischko, Alexandra 24 October 2018 (has links)
No description available.
78

Ruthenium- and Cobalt-Catalyzed C-H Activation

Bu, Qingqing 30 October 2018 (has links)
No description available.
79

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 β-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, β-formyl esters and finally β-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.
80

Ruthenium- and Cobalt-Catalyzed Chelation-Assisted C–H Functionalization

Mei, Ruhuai 31 August 2017 (has links)
No description available.

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