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Item Detecting trace pollutants used on kiwifruit orchards : a thesis presented in partial fulfilment of the requirements of the degree of Master of Philosophy in Chemistry at Massey University, Manawatu, New Zealand(Massey University, 2023) Scott, JacobTrace pollutants from sprays used on kiwifruit orchards are difficult to detect, often requiring sophisticated machinery and sample pre-treatment to detect them at very low levels. There are new techniques being created, but a significant portion of these are expensive, complicated, or are sensitive to interferents. Most techniques use some form of chromatography, but this requires expensive equipment and is slow, however, they can successfully detect the pollutants at very low levels. The use of supramolecular cages to bind and detect these pollutants could remove the need for expensive equipment and speed up the detection process. Supramolecular cages can be tailored to specific pollutants, minimizing the potential for interferences. They can also have a variety of detection mechanisms by adding a detection unit to the cage, allowing for simple testing and the use of cheaper equipment. This project will explore the use of supramolecular cages to bind and detect typical pollutants used in the New Zealand kiwifruit industry.Item Encapsulation of tetrahedral anions in nickel mesocate cages : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Chemistry at Massey University, Manawatu, New Zealand(Massey University, 2022) Park, Chong Yon NicoleFinding ways to isolate anions and metals is a modern problem as concerns over pollution of anions have become popular in the scientific community. The applications of supramolecular structures are endless, ranging from drug delivery to refining metals at an industrial scale. In this thesis, three variations of a di-salicylaldimine linked ligands were designed to form anion encapsulating mesocates. Each ligand differs by the spacer linking the salicylaldimine units. L1 has a six-carbon spacer, L2 has a p-xylylic spacer and L3 has a m-xylylic spacer. After the synthesis and characterisation of these ligands, complexation was achieved with various nickel salts resulting in the formation of dinuclear triple-stranded mesocate complexes; [BF₄⊂Ni₂(L1)₃](BF₄)₃ (C1), [ClO₄⊂Ni₂(L1)₃](ClO₄)₃ (C2) and two dinuclear di-stranded mesocate complexes; [SO₄⊂Ni₂(L3)₂][Ni(SO₄)₂ (EtOH)₄] (C3), [ClO₄⊂Ni₂(L3)₂](ClO₄)₂ (C4). The crystals have been characterised with IR spectroscopy, UV-Vis spectroscopy, mass spectrometry, atomic absorption spectroscopy, conductivity measurements and single crystal X-ray diffraction. An uncommon mesocate structure was observed from the X-ray diffraction data collected whereby the anion in the centre of the cage forms covalent bonds with the two Ni²⁺ metal ions. In addition, metal salt extraction experiments were attempted in a two-phase solvent system with L3, nickel sulfate to assess how much nickel and sulfate could be extracted from the aqueous mixture to the organic solution. Although a reliable measurement of sulfate could not be obtained, the highest percentage of the nickel extracted measured in hexane was 89%. However, there is potential to gather a higher value using the optimal conditions found in these experiments.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 Pyrazine based ligands : supramolecular structures : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Chemistry at Massey University, Manawatū, New Zealand(Massey University, 2021) Donaldson, Marryllyn EmmaPyrazine based ligands have been found to facilitate electronic communication between metal centres, within polynucleated structures. The control of spin states can lead to controllable bistable states of metal centres, in multinucleated supramolecular structures, possibly leading to a physical-materials, with binary analogous properties. These areas are especially of interest to many industries due to the rapidly approaching upper limit in conventional magnetic data storage. The aim of this research is the creation of new pyrazine-based ligands, which can form metal-organic supramolecular complexes, and then investigate the architectures that can be built. The design and synthesis of a new series of ligands based around a central, symmetric, pyrazine-units with functionality on the 2,5- positions was achieved including azide, alkyne and aldehyde groups. These units were than used to synthesise four novel-ligands to contribute to the ever-expanding library of ligands used in supramolecular chemistry. New pyrazine ligands were reacted with a wide range of 3d metal salts, which assembled into eleven 1D polymer chain complexes, and a 3D polymer network. NMR spectroscopy, Mass spectroscopy, ART-IT, X-ray crystallography, and other techniques was utilised to analyse the structural aspects of the ligands and complexes.