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Item Development of a molecular toolbox for multifunctional lanthanide-based supramolecular materials : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry at Massey University, Albany, New Zealand(Massey University, 2022) O'Neil, AlexUsing simple building blocks to develop functional supramolecular materials is an active area of research. To this extent the use of lanthanide ions (Ln³⁺ to direct supramolecular self-assembly with organic ligands has become a popularised method whereby the interesting photophysical properties of Ln³⁺ can be manipulated by simple modification of the organic architecture. Applications of such systems vary from solar waveguides, OLEDS, molecular sensors, contrast agents, bio-probes, security inks and barcodes. Herein, a synthetic strategy has been developed and investigated to readily functionalise the organic scaffolds 2,6-pyridinedicarboxamide (PDA) and 6-carbamoylpyridine-2-carboxcylic acid (PDC), using 1,2,3-triazole “click” chemistry. Using this approach, we have synthesised and assessed the f-directed self-assembly ability of some novel PDA-based and PDC-based assemblies. Initial studies focused on symmetrical incorporation of the 1,2,3-triazole linker into the PDA motif via side carbonyls. This resulted in the development of four ligand architectures (1-4), which in the presence of Eu³⁺ and Tb³⁺ self-assemble into Ln(L)₃ (CF₃SO₃)₃ (where L = 1-3) luminescent assemblies. While results of the PDA systems were promising, the systems were relatively unstable in competitive solvents, and as a result subsequent systems focused on the unsymmetrical modification of the PDC motif. Incorporation of our synthetic strategy into the PDC motif was straightforward and additionally improved both Ln³⁺ complex stability and emission intensity. Using this approach, amphiphilic ligand 5 and visibly emissive amphiphilic complexes Ln(5)₃ (where Ln = Eu³⁺, Tb³⁺, Sm³⁺ and Dy³⁺) were synthesised. The incorporation of a long alkane chain via the 1,2,3-triazole in ligand 5 allowed for the fabrication of ultra-thin luminescent films by Langmuir-Blodgett (LB) technique resulting in bright visibly emissive monolayer films. Furthermore, mixing of the emissive Ln(5)₃ complexes resulted in tunable emission dependent on the composition in both solution and monolayer film. Following this, single component dual emissive systems Ln(6)₃, [Ln(7)₃](CF₃SO₃)₃ and Ln(8)₃ were developed. This entailed the incorporation of blue emissive 1,8-naphthalimide (6 & 7) and pyrene (8) via the 1,2,3-triazole linker. When complexed with Eu³⁺ it resulted in dual emissive systems which were colour-tunable, changing colour dependent on the excitation wavelength, and in the case of Eu(6)₃ and Eu(8)₃ it results in white emissive solids and solutions. These properties were transferable to thin films, by spin coating techniques. Finally, the synthetic strategy was used in the initial development of multi-nuclear assemblies forming three multitopic ligands (9-11) and initial complexation studies were undertaken.Item Towards DNA-chromophore supramolecular assemblies for photon upconversion : a thesis submitted in the partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry, Massey University, Palmerston North, New Zealand(Massey University, 2015) Mutsamwira, SaymoreThe interactions of long DNAs of biological origin with small molecules have intrigued scientists for a while now, with particular emphasis on medical applications like cancer therapy. Recently, DNA’s unique highly ordered structures, selfassembly capabilities and ease of chemical modification have led to a more broad based approach for potential applications in photonic and electronic devices. In this thesis, we show that DNA can be used as a scaffold for supramolecular assembly of selected organic chromophores for tuning photon upconversion based on a triplettriplet annihilation (TTA) mechanism. Green-to-blue photon upconversion was observed using tris(bipyridine)ruthenium(II), [Ru(bpy)3]2+ as a long wavelength absorber and an insitu energy donor to an acceptor (R)-1-O-[4-(1- pyrenylethynyl)phenylmethyl]glycerol), abbreviated PEPy and also known as a twisted intercalating nucleic acid (TINA) monomer which acts as an annihilator and short wavelength photoemitter. This result prompted us to investigate interactions of the ligands ([Ru(bpy)3]2+ and ZnTMpyP4, the Zn2+ derivative of 5,10,15,20-tetrakis- (1-methyl-4-pyridyl)-21H,23H-porphine) with TINA moieties attached to a DNA scaffold. Zinc metallated porphyrins and ruthenium polypyridyl complexes are well known to act as donors in TTA-based energy upconversion. TINA-modified DNA duplexes and G-quadruplexes significantly improved the interaction between TINA and ZnTMpyP4/ [Ru(bpy)3]2+ as shown by fluorescence, circular dichroism (CD), and UV-Vis spectroscopy studies. In contrast to dynamic quenching of the TINA monomer fluorescence by [Ru(bpy)3]2+ and ZnTMpyP4 for free monomers in solution, ground state complex formation was the predominant mechanism of interaction between TINA-modified DNAs and [Ru(bpy)3]2+/ ZnTMpyP4. Energy upconversion was observed with a [Ru(bpy)3]2+ donor and TINA-modified DNAs. The results presented in this thesis lay a foundation for further energy upconversion studies utilizing appropriate organic chromophores using DNA as a scaffold.Item The solution and solid state analysis of xylylic di-copper complexes as receptors for encapsulating anions : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Chemistry at Massey University, Palmerston North, New Zealand(Massey University, 2011) Stevens, James RawiriThe investigation into neutral aryl-linked oxime dicopper helicates encapsulating a number of anions was carried out. Two dicopper aryl-linked salicyloxime derived complexes were synthesized and studied which contained either p-xylylic (1) or m-xylylic (2) incorporated spacer groups. UV-visible spectroscopy was used to determine the binding stability constants of the anion complexes. Complex binding, encapsulation of anions and the conformational flexibility of 1 and 2 was supported and ascertained by the crystal structural data obtained. Receptor 1 expressed an exceptional binding strength for sulfate in THF where a log K value of 5.5 ± 0.3 was acquired. Receptor 2 could form both helical and non-helical structures. This was able to bind bromide selectively in a 2:1 stoichiometry of anion:receptor with a log K2 value of 9.2 ± 0.1 and showed an unexpectedly high association constant for the perchlorate anion in a 1:1 stoichiometry with a log K value of 4.6 ± 0.2 (presumably in a helical structure).