Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.761819
Title: A study in ring expansion
Author: Curran, Adrian Charles Ward
Awarding Body: University of Glasgow
Current Institution: University of Glasgow
Date of Award: 1967
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Abstract:
Part I: The acid catalysed ring expansion reaction of 2-(3'-phenyl-3'-oxopropyl)-cyclopentanone to 4-phenylcyclo-hept-3-ene carboxylic acid, has been extended to include substituted aromatic and wholly aliphatic 1,5-diketones. In the case of the latter, where tetrahydroindanones proved to be the thermodynamically favoured product, modified conditions have been developed to afford the alkyl substituted cycloheptene carboxylic acids. The synthetic applicability of the reaction has been studied as a potential route to the alkaloid colchicine and to the guaianolide sesquiterpenes. Part II: The structure of Mannich bases arising from unsymm-etrical ketones has been related to the direction of acid catalysed enolisation. A parallel n. m. r. study of Mannich bases and their quaternary salts revealed useful information regarding the chemical shift of protons in the proximity of the quaternised centre. The hitherto disputed existence of a mixture of isomeric Mannich bases arising from unsymmetrical ketones (e. g. isopropy methyl ketone) has been unambiguously proved and and subsequently related to the isomeric mixture of enols formed under acidic conditions. beta,beta-Disubstituted Mannich bases have been convincingly shown to be capable of rearrangement under certain conditions (e. g. in the thermal Michael reaction) thus causing them to behave as their isomeric bases. The corresponding quaternary salts are not involved in any rearrangement process.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.761819  DOI: Not available
Keywords: QD Chemistry
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