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dc.contributor.advisorKilian, Petr
dc.contributor.authorSomisara, Dhanasekara M. U. K.
dc.description.abstractThe rac- and meso- forms of “all carbon” 1,2-diphosphonium dications with the naphthalene -1,8-diyl backbone were synthesised in good yields and purity by double alkylation of the parent diphosphine (1,2-diphenyl-1,2-diphosphaacenaphthene) using strong alkylating agents. Pure rac- and meso- forms of 1,2-diphosphoniums were obtained diastereospecifically by using methyl triflate and trimethyloxonium tetrafluoroborate respectively. It was found that the equilibrium between the rac- and meso- forms at room temperature in acetonitrile solutions effectively depends on the anion present. A reaction mechanism which proceeds via a P-pentacoordinated intermediate was proposed for the epimerisation observed between the rac- and meso- forms in the presence of F⁻ donors in the solution. Reactivity of the new 1,2-dications towards a range of compounds (nucleophiles, bases) was examined and a series of new compounds including phosphine-phosphoniums and phosphonium-phosphine oxides were obtained. Cyclic and acyclic compounds belonging to a novel group of phosphine-arsine mixed peri-substituted acenaphthenes were synthesised by introducing arsenic and phosphorus to the acenaphthene ring, using stepwise lithiation and carbon-group 15 element coupling. All new compounds were fully characterised including single crystal X-ray diffraction. The effect of the peri-substitution by phosphorus moieties and mixed arsine-phosphine peri-substitution on the naphthalene ring was studied using the detailed structural data obtained for these systems.en_US
dc.publisherUniversity of St Andrews
dc.subject1,2-diphosphonium dicationsen_US
dc.subject.lcshOrganophosphorus compoundsen_US
dc.subject.lcshOrganoarsenic compoundsen_US
dc.titleSynthetic studies into phosphorus and arsenic peri-substituted naphthaleneen_US
dc.type.qualificationnamePhD Doctor of Philosophyen_US
dc.publisher.institutionThe University of St Andrewsen_US
dc.rights.embargodatePrint and electronic copy restricted until 20th June 2018en_US
dc.rights.embargoreasonThesis restricted in accordance with University regulationsen_US

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