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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.
61

Oxazaborolidine-mediated reduction of prochiral 2-alkylidene cycoalkanones

Simpson, Alison Fiona January 1999 (has links)
No description available.
62

New enantioselective metal-catalysed conjugate addition-initiated reactions of alkenyl(aza)arenes

Saxena, Aakarsh January 2013 (has links)
I. Enantioselective Rhodium-Catalysed Arylation of Electron-Deficient Alkenylarenes β-substituted alkenyl-para-nitroarenes, an unexplored substrate class for catalytic asymmetric addition reactions, undergo highly enantioselective rhodium-catalysed arylations with arylboronic acids in the presence of a dibenzylamide-containing chiral diene ligand. One example of the asymmetric arylation of an alkenyl-p-cyano-m-( trifluoromethyl)benzene is also reported. The scope of this process is broad with variation in the β-position of the alkene, additional substituents on the electrondeficient arene, and sterically and electronically unique arylboronic acids all tolerated. The synthetic utility of the developed methodology is demonstrated by smoothly converting one arylated product into its corresponding indole via the Bartoli reaction. II. Enantioselective Copper-Catalysed Reductive Coupling of Alkenylazaarenes with Ketones Catalytic enantioselective methods for the preparation of chiral azarene-containing compounds are of high value. By combining the utility of copper hydride catalysis with the ability of C=N-containing azaarenes to activate adjacent alkenes toward nucleophilic additions, the enantioselective reductive coupling of alkenylazaarenes with ketones has been developed. The process is tolerant of a wide variety of azaarenes and ketones, and provides aromatic heterocycles bearing tertiary-alcoholcontaining sidechains with high levels of diastereo- and enantioselection.
63

The synthesis and application of novel chiral transition metal complexes

Green, Simon Michael January 1999 (has links)
No description available.
64

Novel cyclopentadienyl transition metal complexes

Veighy, Clifford Robert January 2001 (has links)
No description available.
65

Enantioselective synthesis of oxygenated hydrocarbons by biotransformation

Archer, Ian Victor James January 1996 (has links)
No description available.
66

The development of a general method for the asymmetric epoxidation of electron deficient alkenes

Elston, Catherine L. January 1996 (has links)
No description available.
67

Asymmetric allylic and progargylic oxidation reactions

Tolhurst, Keith F. January 1998 (has links)
No description available.
68

The synthesis of homochiral polythiophenes

Golighar, Abdul Munaff January 1995 (has links)
No description available.
69

Implementation of a modular Fly away Kits (FLAK) for C4ISR in order to counter asymmetric threats in the coalition riverine and maritime theatres

Hochstedler, Robert A. 06 1900 (has links)
This research analyzes the design and implementation of a Maritime Command, Control, Computer, and Communications for Intelligence, Surveillance, and Reconnaissance (C4ISR) fly away kit (FLAK) in order to combat asymmetric threats in the coalition maritime environment. This FLAK will be modular, adaptable, scalable, and secure end to end, composed of routable networks, and built entirely from commercial off the shelf technologies (COTS). Basing measures of effectiveness (MOE) on the recently published Quadrennial Defense Report (QDR) and the Numbered Fleet Commanders Communication Message, these kits will be tested with the goal of fulfilling thirteen of the fifteen high priority short-falls in the modern United States CIV-MIL and Coalition Forces' abilities to conduct multiple missions in the current brown (riverine), green (littoral), and blue (deep water) operational theatres. The Maritime FLAK will be designed with the intent of increasing the US forward presence and extending the C4ISR into restricted maritime theatres. Since US forces cannot intervene directly into regions like the Straits of Malacca, but can support coalition forces through advisors and technological adaptations, modular solutions to extend C4ISR into these maritime territories are needed. Furthermore, due to the adaptability and scalability of the technologies to be implemented into the maritime FLAK, these completed kits will be able to be used by the recently formed Naval Expeditionary Combat Command (NECC) in current operations in the Global War on Terrorism. / US Navy (USN) author.
70

Asymmetric synthesis of β- and γ- amino acids

Zammit, Charlotte Maria January 2015 (has links)
This thesis is concerned with the development of new synthetic routes for the asymmetric syntheses of a range of β- and γ-amino acids. Chapter 1 introduces the various biological activities displayed by cyclic β-amino acid containing compounds together with their occurrence in pharmaceutical molecules and β-peptides. Some of the most commonly used synthetic strategies for the preparation of carbocyclic β-amino acids are briefly described, with the focus on the formation and functionalisation of a five-membered carbocyclic ring. Chapter 2 describes a full investigation into a highly diastereoselective Ireland-Claisen rearrangement of stereodefined allyl β-amino esters to access enantiopure α-substituted β-amino acid products. The synthetic utility of this methodology is highlighted by its application in the asymmetric syntheses of five previously inaccessible C(5)-substituted 1,2-anti-1,5-syn-transpentacins. Chapter 3 delineates investigations into a highly diastereoselective conjugate additionelimination protocol for the preparation of a cyclic β'-amino-α,β-unsaturated ester. Subsequent chemo- and diastereoselective conjugate addition reactions of Grignard reagents and lithium amides to this substrate enabled the asymmetric syntheses of four C(5)-substituted 1,2-anti-1,5-syn-transpentacins and two five-membered β,β'-diamines. Chapter 4 details the extension of the protocol developed in Chapter 3 for the conjugate addition of Grignard reagents to a range of acyclic γ-(N,N-dibenzylamino)-substituted α,β-unsaturated esters. Elaboration of the β,γ-disubstituted γ-amino ester products culminated in the asymmetric syntheses of six β,γ-disubstituted γ-amino acids. Chapter 5 chronicles the preparation of an azabicyclic α,β-unsaturated ester, following which attempts towards the asymmetric synthesis of various substituted pyrrolizidines using a conjugate addition protocol are subsequently described. Chapter 6 contains full experimental procedures and characterisation data for all compounds synthesised in Chapters 2, 3, 4 and 5.

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