Show simple item record

dc.contributor.advisorMurphy, Paul V.
dc.contributor.authorFarrell, Mark
dc.date.accessioned2014-10-16T14:39:01Z
dc.date.issued2014-04-07
dc.identifier.urihttp://hdl.handle.net/10379/4641
dc.description.abstractThis thesis deals with the anomerisation of glycosidic linkages using TiCl4 and SnCl4. Methods involving the Lewis acid induced anomerisations of glycosides have been published over the past decade, however this methodology has not been widely utilised in carbohydrate chemistry due to low yields, large variations in selectivity, and the need for specific functional groups (e.g., carbamate). It is felt that a better understanding of the anomerisation reaction could be achieved by probing the effects of protecting groups and pushing the reaction to it limits. Chapter 1 deals with the anomerisation of glycosyl azides. Previous work by Murphy et al. has led to reasonable but not high selectivity using SnCl4. Since this work was carried out a seminal publication by Murphy et al. demonstrated the advantages of using TiCl4 in anomerisation reactions. The application of TiCl4 and varying the carboxylic functionality from acid to ester gave the desired high selectivities in good yields. Chapter 2 applies this successful approach to the anomerisation of disaccharide substrates, resulting in regioselective anomerisations and giving the desired alpha-products in high selectivities and yields. Chapter 3 deals with the influence of protecting groups on the rate of the anomerisation reaction. The rate of anomerisation for has been quantified for 34 substrates in an attempt to elucidate the influence of the steric and electronic effects. It was evident from the results obtained that both steric and electronic effects have an influence on the rate of anomerisation.en_US
dc.subjectCarbohydrateen_US
dc.subjectSynthesisen_US
dc.subjectOrganic chemistryen_US
dc.subjectDepartment of Chemistryen_US
dc.subjectSchool of Natural Sciencesen_US
dc.titleThe anomerisation of glycosidic linkagesen_US
dc.typeThesisen_US
dc.contributor.funderIRCSET-Roche Irelanden_US
dc.local.noteThis thesis outlines a method which can be utilized to prepare glycosidic linkages in a selective manner, which is not easily achieved.en_US
dc.description.embargo2017-07-04
dc.local.finalYesen_US
nui.item.downloads126


Files in this item

Attribution-NonCommercial-NoDerivs 3.0 Ireland
This item is available under the Attribution-NonCommercial-NoDerivs 3.0 Ireland. No item may be reproduced for commercial purposes. Please refer to the publisher's URL where this is made available, or to notes contained in the item itself. Other terms may apply.

The following license files are associated with this item:

Thumbnail

This item appears in the following Collection(s)

Show simple item record