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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.
41

Novel calixpyrrole-like anion receptors

An, Deqiang 28 August 2008 (has links)
Not available / text
42

Synthesis and characterization of some organoruthenium complexes with macrocyclic amine ligands

蔡美玉, Choi, Mei-yuk. January 1999 (has links)
published_or_final_version / Chemistry / Master / Master of Philosophy
43

Organic oxidation catalysed by ruthenium and manganese macrocycles

楊志雄, Yeung, Chi-hung. January 1993 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
44

A study of the attachment of a palladium molecular square to a planar gold surface or nanoparticle

Miller, Benjamin I. January 2006 (has links)
We plan to study the attachment of a cationic tetranuclear palladium II-based macrocyclic square onto a planar gold surface or a gold nanoparticle. To understand the possible mechanisms of attachment of inorganic molecular square to gold we will see if certain related salts can cause an induced aggregation of nanoparticles.The replacement of the surface-passivated citrate layer on the gold nanoparticles can be characterized by infrared spectroscopy and shifts in the surface plasmon resonance band. Consequently, if it can bond gold nanoparticles via electrostatic interactions, then it may be possible that the square can attach to a planar gold surface by a similar mechanism.Infrared spectra of the aggregated nanoparticles will be compared to those obtained using the attachment of molecular square on a planar gold surface. By comparing.infrared spectra it may be possible to determine by what mechanism the square is attaching to gold. / Department of Chemistry
45

The supramolecular chemistry of cucurbituril molecules

Lorenzo, Susan, Chemistry, Faculty of Science, UNSW January 2006 (has links)
The set of molecules cucurbit[n]uril (Qn) are macrocycles composed of n glycoluril monomers linked by methylene groups. These molecules have two oxygen-ringed portals of a diameter slightly smaller than their internal cavity diameter. This thesis describes syntheses, crystallisations, crystal structure determinations, crystal packing analyses and force field calculations exploring the supramolecular chemistry of Qn molecules and their derivatives. Qn acts as a host for guest molecules and at the outset of this project no metal containing molecule had been encapsulated in a Qn molecule. One aim of this project was to prepare such complexes. This was achieved with the synthesis and characterisation of crystalline {[cis-SnCl4(H2O)2]@Q7}2(SnCl6)3(H3O)6(H2O)23. Other compounds prepared and characterised crystallographically in the course of this project are: [(Q6)(Na3(H2O)8)]2[CoCl4]4[Co(H2O)6]2[CoCl(H2O)5]2(Cl)4, (Q5@Q10)(CH3COOH)(Cl)2(H3O)2(H2O)26, (Cl@Q5)4Q6(SnCl6)8(H3O)20(H2O)24, (Q8)3(PtCl6)4(H3O)8(H2O)x, (Q8)2(PtCl6)3(H3O)6(H2O)18, (Q7)(Cr3O10)(H3O)2(H2O)x and (Q6)(SnCl6)(H3O)2(H2O)x. While the smaller Qn (n = 5?) retain their circular forms, the larger Qn (n &gt 8) are less rigid and distort to accommodate larger guests. After analysis of the crystal structures of these Qn compounds and those listed in the Cambridge Structural Database, the principal packing motifs of the Qn molecules were elucidated. The most common is the portal-to-side interaction in which the portal oxygen atoms of one Qn approach the hydrogen atoms around the equator of another Qn. Force-field calculations on guest@Qn complexes were conducted to determine the mechanism for the formation of these complexes. A comparison of the intermolecular interactions of phenylated systems and comparable fluorinated phenyl systems was made using both crystal packing analyses and forcefield energy calculations. Intermolecular energy parameters for these calculations were derived and validated in this work. The principal fluorinated species studied was the [B(C6F5)4]?anion. Examination of its crystal structures found that the substitution of the hydrogen atoms by fluorine atoms is influential enough to alter the predominant intramolecular conformation. It is the ???flipper?conformer, between pairs of perfluorophenyl groups, that is overwhelmingly the favoured conformation and this has a strong effect on the types of phenyl embraces that a [B(C6F5)4]?anion will form. While the parallel 4PFE, the offset parallel 4PFE and the orthogonal 4PFE are all observed the 6PFE is not.
46

Synthesis of new heterocyclic structures based on indoles

Somphol, Kittiya, Chemistry, Faculty of Science, UNSW January 2007 (has links)
Novel indolo-macrocycles have been generated from the attempts to synthesise bis-indolo-cyclotriveratrylenes by the condensation of I, I'-diindolyl-3,3'-dimethanols catalysed by p-toluenesulfonic acid. The addition of substituents on indoles led to enhanced solubilities of the macrocycles. Nine- and six-membered ring compounds have been synthesized from the acid-catalysed reaction of I,I'-diindolyl compounds and aryl aldehydes. Some reactions of these compounds and the attempted synthesis of 2,2' diindolylmethanes from the cyclic compounds have also been described. The electrophilic substitution reactions of 3-substituted 4,6-dimethoxyindole 2,6-dimethanols and 3-substituted 4,6-dimethoxyindole-7 and 2-carbaldehydes and I-substituted indoles afforded triindolyl dialdehydes. The wriation of substituents at C-7 of indole-7-aldehydes and at C-2 of indole-2-aldehydes has also been discussed. Reaction of the hydroxymethylindole and 1,2-di(indol-I-ylmethyl)benzene gave a new macrocycle. Substitution reactions of 2,2???-diindolylmethane-7,7'-dimethanol and indole-7- and 2-aldehydes gave tetraindolyl dialdehydes. Sodium borohydride reduction of tri- and tetra-indolyl dialdehydes gave tri- and tetra-indolyl dimethanols respectively. Acid-catalysed reactions of tri- and tetra-indolyl dimethanols afforded only calix[3] and [4]indoles respectively when all substituents at C-3 of indoles were aryl groups. New conditions for indole based imine synthesis have been established Macrocyclic imine formation from mono-, di-, tri and tetra-indolyl dialdehydes has been investigated. Reactions of indole-3, 7-dialdehydes and short chain diamines (1,2-diaminoethane, 1,2-diaminobenzene and 1,6-diaminohexane) gave mixtures while the reactions with long chain diamines (1,10 diaminodecane and 1,12-diaminododecane) gave monoindolyl macrocyclic imines. Reaction of indole-2, 7-dialdehydes and short chain diamines afforded diindolyl macrocyclic imines with head-tail structures, and the 2,7';2',2";7",2'''-Tetraindole-7 ,7"'-dialdehyde underwent cyclisation with triindolyl dialdehydes and 1,6-diaminohexane afforded triindolyl macrocyclic imines. 1,2 diaminoethane while the 2,3 ';1',1 ";3 ",2"'-tetraindole-7,7"'-dialdehydes underwent imine, with its precise structure established by X-ray crystallography. Reaction of of 1,3-di(indol-l-ylmethyl)benzene and 1,2 diaminoethane yielded a new macrocyclic reactions with long chain diamines yielded monoindolyl macrocyclic imines. Reaction ring closure with 1,2 diaminoethane and 1,6-diaminohexane.
47

Crown ethers as potential lead (II) specific probes : a thesis submitted for the degree of Doctor of Philosophy / by Daniela Caiazza.

Caiazza, Daniela January 1999 (has links)
Errata pasted onto front end-paper. / Bibliography: leaves 173-188. / xii, 188 leaves : ill. (chiefly col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Describes a comprehensive study of a select but informative set of crown ether ligands that may potentially be used in the development of a fluorescent lead (II) specific probe. / Thesis (Ph.D.)--University of Adelaide, Dept. of Chemistry, 1999
48

Syntheses and coordination studies of [9]aneN3 substituted with increasing numbers of 2-hydroxyethyl pendant arms / Steffen Phillip Creaser.

Creaser, Steffen Phillip January 1999 (has links)
Copies of author's previously published articles inserted. / Bibliography: leaves 176-187. / xiii, 187 leaves ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Describes the syntheses of three 1,4,7-triazayclonane macrocyclic ligands functionalised with increasing numbers of 2-hydroxyethyl pendant arms. / Thesis (Ph.D.)--University of Adelaide, Dept. of Chemistry, 1999
49

Design, synthesis, and photophysical and electrochemical studies of redox-active macrocyclic dinuclear transition metal complexes as potential molecular switches

Kong, Jianfei. January 2009 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 214-229). Also available in print.
50

Novel calixpyrrole-like anion receptors

An, Deqiang, Sessler, Jonathan L., January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisor: Jonathan L. Sessler. Vita. Includes bibliographical references. Available also from UMI company.

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