Studies in molecular, supramolecular and macromolecular design.
| dc.contributor.advisor | Lincoln, Stephen Frederick | en |
| dc.contributor.advisor | Pyke, Simon Matthew | en |
| dc.contributor.author | Archer, Oscar | en |
| dc.contributor.school | School of Chemistry and Physics | en |
| dc.date.issued | 2011 | en |
| dc.description.abstract | This thesis will be in three parts describing three projects which investigated different areas of new materials science in the context of nanotechnological chemistry. The parts include: the synthesis and characterisation of novel metalloporphyrin complexes with the geometry of ‘molecular cogs’; physical analysis of simple, new cyclodextrin-based inclusion compounds, and attempts to generate rotaxanes there-from; and analysis of the behaviour of aromatic hydrophobically-modified water-soluble polymers as components in supramolecular complexing complementary polymer systems. A synthetic approach through a vinyl sulfone–modified Barton and Zard pyrrole was successfully utilised. It was envisaged that this functionality could be extended further into a cyclic spiro substituent: where the spiro functionality incorporated aromaticity, it would constitute a planar, non-rotating substituent arranged orthogonally to the macrocyclic plane. Symmetrical, tetraspiro annulated porphyrin systems including indanyl and fluorenyl derivatives were synthesised and spectroscopically characterised. The fluorenyl-derived zinc metalloporphyrin gave suitable crystals for X-ray crystallographic analysis. The design and synthesis of a series of cyclodextrin inclusion compounds incorporating relatively simple amino-substituted biaryl axle was carried out. The pseudorotaxanes were asymmetric in character, incorporating functionalised homo- and heteroaromatic rings at either end, joined by an unsaturated linker. The heterocycle was an azine ring (pyridine or pyrimidine), and therefore bore one or more nitrogen protonation sites; pK[subscript]a s in water-methanol solutions were determined. Distinct inclusion in a-cyclodextrin was observed and quantified in dilute basic aqueous solution by UV-visible spectroscopy. Corresponding inclusion in concentrated acidic conditions was studied through 2D NMR techniques, revealing a clear temperature dependence for the a-cyclodextrin/pyridine based axle, and site-exchange analysis was performed to determine the rate of inclusion compound formation. Generation of corresponding rotaxanes was not achieved, most likely due to the reactivity of azine ring-bound amine groups in the necessary reaction conditions. The range of hydrophobically modified polymers was expanded by appending amide- bonded aromatic side chains to poly(acrylic acid), to give phenyl-, diphenyl-, naphthyl- and anthryl-type modification. This procedure allowed control over the molecular weights of the polymer products, and a degree of direction of the amount of each new polymer’s modification observed primarily through 2D NMR techniques, and absorbance/fluorescence where applicable. It was generally found that aromatic substituents lacked the tendency to aggregate in solution that is observed for long polymer-bound alkyl groups. This is likely due to the relative length and rigidity of aromatic species. For naphthyl and anthryl groups excimer emission would be a likely consequence of aggregation but its absence suggests that π-CH hydrophobic association between aromatic groups and the alkane backbone is more favoured. For the anthryl- bearing polymer in particular this means that the likely form of substitution consistent with the fluorescence data is not suitable for studying anthracene fluorescence behaviour in an aqueous-polymer environment. The interactions of these modified polymers with native α- and β-cyclodextrin and the corresponding cyclodextrin-modified PAAs in aqueous solution were assessed with 2D NOESY NMR spectroscopy. | en |
| dc.description.dissertation | Thesis (Ph.D.) -- University of Adelaide, School of Chemistry and Physics,, 2011 | en |
| dc.identifier.uri | http://hdl.handle.net/2440/71034 | |
| dc.provenance | Copyright material removed from digital thesis. See print copy in University of Adelaide Library for full text. | en |
| dc.subject | porphyrin; cyclodextrin; poly (acrylic acid); rotaxane; spiro-annulation | en |
| dc.title | Studies in molecular, supramolecular and macromolecular design. | en |
| dc.type | Thesis | en |