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dc.contributor.advisorClarke, Matt
dc.contributor.authorJones, Charlotte E. S.
dc.coverage.spatial229en_US
dc.date.accessioned2012-05-23T09:35:51Z
dc.date.available2012-05-23T09:35:51Z
dc.date.issued2011-06
dc.identifieruk.bl.ethos.552706
dc.identifier.urihttp://hdl.handle.net/10023/2611
dc.description.abstractThis thesis is divided into three main results chapters that reflect the path my research took. In the first results chapter, the first organocatalyst for the carbonyl-ene reaction was discovered and found to give high conversion using 1,3-bis(3,5-bis(trifluoromethyl)phenyl)thiourea. Various carbonyl and alkene precursors were examined in the ene reaction in both catalysed and uncatalysed reactions. It was found that ene reactions using fluoral and ethyl trifluoropyruvate give higher rates of reaction when compared to other carbonyl compounds. A novel enantiopure thiourea was synthesised and the ene reaction was catalysed enantioselectively to 33% e.e. In an attempt to catalyse the reaction to a further extent a new thiourea bonded to a P(=S)R2 group was developed. However, the intramolecular hydrogen bonding of this catalyst was thought to be so strong that this it did not catalyse the reaction. The synthesis of a chiral phosphoric acid was achieved but this was an unsuccessful catalyst in the ene reaction. Two component achiral thiourea and chiral acids were also examined in the ene and Mannich-type reaction. The new easily synthesised thiourea for this reaction has an interesting intermolecular hydrogen bonding coordination in the solid state. Asymmetric fluorination of ketoesters using palladium is a dynamic kinetic resolution. In the 2nd chapter cationic palladium complexes were synthesised and used to determine the optimum parameters for bidentate ligands in this reaction. Four carbon chain phosphines were found to give the highest conversion for this reaction among those ligands tested such as 1,4-bisdiphenylphosphinobutane (bite angle 99º). A new bis-phosphinous amide chiral ligand was developed with a bite angle of 96.7º. The dichloropalladium complex of this phosphine was isolated and structurally characterised. The use of the palladium complex in asymmetric fluorination was attempted however this was found to be unsuccessful. Mechanistic studies reveal that the formation of the desired cationic catalyst did not occur under conditions shown to work well for other palladium phosphine complexes. The ligand was investigated further in hydrogenation reactions. The phosphinous amide was protected as its borane and was used in the rhodium catalysed hydrogenation of alkenes to give high conversion and up to 93% e.e. The borane protected phosphinous amide was also found to catalyse the hydrogenation of acetophenone using copper complexes with up to 84% e.e for the hydrogenation of acetophenone, although conversion was quite low.en_US
dc.language.isoenen_US
dc.publisherUniversity of St Andrews
dc.subjectAsymmetric catalysisen_US
dc.subjectOrganocatalysisen_US
dc.subjectEne reactionen_US
dc.subjectFluorinationen_US
dc.subjectHydrogenationen_US
dc.subjectThioureaen_US
dc.subject.lccQD505.J7
dc.subject.lcshAsymmetric synthesisen_US
dc.subject.lcshCatalysisen_US
dc.subject.lcshEnantioselective catalysisen_US
dc.subject.lcshOrganofluorine compounds--Synthesisen_US
dc.subject.lcshHydrogenationen_US
dc.subject.lcshThioureaen_US
dc.titleEnantioselective homogeneous catalysts for the synthesis of fluorinated organic compoundsen_US
dc.typeThesisen_US
dc.type.qualificationlevelDoctoralen_US
dc.type.qualificationnamePhD Doctor of Philosophyen_US
dc.publisher.institutionThe University of St Andrewsen_US


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