Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.651939
Title: Metallo-cyclodextrins : building blocks in non-covalent assemblies of photoactive units for the study of photo-induced intercomponent processes
Author: Haider, Johanna M.
Awarding Body: University of Edinburgh
Current Institution: University of Edinburgh
Date of Award: 2001
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Abstract:
Cyclodextrin receptors have been employed to build supramolecular systems consisting of metal and organic photo/redox-active components. The photo-induced communication between redox-active units assembled in water via non-covalent interactions is established. Receptor ligands consisting of a β-cyclodextrin functionalised with a terpyridine or bipyridine unit, ttp-β-CD and mbpy-β-CD respectively, and their ruthenium(II) metal complexes [(ttp-β-CD)Ru(ttp)][PF6]2, [(ttp­β-CD)Ru(tpy)][PF6]2, [(ttp-β-CD)2Ru][PF6]2, and [(mbpy-β-CD)3Ru][PF6]2 are synthesised and fully characterised. Addition of redox active guests, such as quinones, to aqueous solutions of [(ttp-β-CD)Ru(ttp)][PF6]2 or [(mbpy-β-CD)3Ru][PF6]2, leads to a quenching of the 3MLCT emission which is attributed to intramolecular electron transfer from the ruthenium centre to the non-covalently bound guest in the cyclodextrin cavity. Metallo acceptor guests with a hydrophobic binding unit to assure assembly in the cyclodextrin, such as [(biptpy)Os(tpy)][PF6]2 are investigated to study metal-metal communication. Time resolved spectroscopy and steady state experimental results are given. Binding studies with permethylated β-cyclodextrin to obtain association constants of anthraquinone-4-sulfonic acid, anthraquinone-4-caxboxylic acid and benroquine are performed by emission spectroscopy. Inclusion of a biphenyl unit in permethylated β-cyclodextrin is studied by UV/Vis spectroscopy, using 4’-(p-biphenyl)-2,2’:6’2”-terpyridine and Zn(biptpy)][PF6]2 as model compounds for a 1:1 and 1:2 inclusion complex formation respectively. The assembly of cyclodextrin recognition sites in macromolecular structures by using simple coordination chemistry is presented. Tris-cyclodextrin complexes are prepared by reaction of the bidentate ligand mbpy-β-CD with iron(II) and rutheniuim(II) or by reaction of the tertendare ligand ttp-β-CD with europium(III). Bis-cyclodextrin complexes axe obtained by addition of iron(II) to ttp-β-CD. The characterisation of the compounds and their luminescent properties are reported.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.651939  DOI: Not available
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