Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.659574
Title: Synthesis of metal based interlocked architectures : spanning through oxidation states, geometries and coordination motifs
Author: Morelli, Alessandra
Awarding Body: University of Edinburgh
Current Institution: University of Edinburgh
Date of Award: 2004
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Abstract:
Efficient synthetic methods have been developed for catenates and rotaxanes based on tetrahedral and trigonal bipyrimidal metal complexes using the metal-bis-phenanthroline synthon pioneered in Strasbourg. The aim of this project was to investigate the possibility to synthesise mechanically interlocked architecture using metals with higher oxidation states, different geometries and higher coordination motifs. Chapter Two describes the synthesis of a general ligand system for rotaxane complexes of ions that prefer octahedral coordination – the commonest ligand geometry amongst transition metals but up to now a rare coordination mode for rotaxanes. Simple mixing of the components at room temperature is sufficient to assemble a broad range of octahedrally coordinated metal-[2]rotaxanes in excellent yields. The reactions have few, if any, by products and proceed under thermodynamic control in the absence of a catalyst or any other external reagents. Chapter Three reports the template-directed synthesis of a [2]catenate and a [2]rotaxane by a clipping approach around trivalent octahedral cobalt ions. Chapter Four reports the design and investigation of the synthesis of pentacoordinate rotaxane about divalent zinc and cadmium metals and of tetracoordinate rotaxane about divalent palladium. A clipping approach as well as a threading-and-capping approach were considered for both geometries, leading to interesting results involving the kinetics and thermodynamics of each complex. Zinc was suitable for the self-assembling of the macrocycle about the metal-thread complex but failed to hold the unstoppered thread in place to undergo capping reaction; cadmium on the contrary yielded rotaxane upon threading approach but lead to the formation of more thermodynamically stable hexacoordinate catenate upon ligand self-assembly via clipping approach. Palladium did not promote any self-organization towards the assembly of the macrocycle via clipping approach about the preformed thread.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.659574  DOI: Not available
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