dc.check.chapterOfThesis	2,3
dc.check.embargoformat	E-thesis on CORA only	en
dc.check.opt-out	Not applicable	en
dc.check.reason	This thesis is due for publication or the author is actively seeking to publish this material	en
dc.contributor.advisor	Maguire, Anita R.	en
dc.contributor.author	O'Mahony, Graham E.
dc.contributor.funder	Irish Research Council for Science Engineering and Technology	en
dc.date.accessioned	2013-07-11T14:23:15Z
dc.date.available	2014-07-12T04:00:05Z
dc.date.issued	2013
dc.date.submitted	2013
dc.description.abstract	The focus of this thesis is the preparation of enantiopure sulfoxides by means of copper-catalysed asymmetric sulfoxidation, with particular emphasis on the synthesis of aryl benzyl and aryl alkyl sulfoxides. Chapter 1 contains a review of the methods employed for the asymmetric synthesis of sulfoxides, compounds with many applications in stereoselective synthesis and in some cases with pharmaceutical application. Chapter 1 describes asymmetric oxidation, including metal-catalysed, non metal-catalysed and enzyme-catalysed, in addition to synthetic approaches via nucleophilic substitution of appropriately substituted precursors. Kinetic resolution in oxidation of sulfoxides to the analogous sulfones is also discussed; in certain cases, access to enantioenriched sulfoxides can be achieved via a combination of asymmetric sulfoxidation and complementary kinetic resolution. The design and synthesis of a series of sulfides to enable exploration of the substituent effects of the copper-mediated oxidation was undertaken, and oxidation to the racemic sulfoxides and sulfones to provide reference samples was conducted. Oxidation of the sulfides using copper-Schiff base catalysis was undertaken leading to enantioenriched sulfoxides. The procedure employed is clean, inexpensive, not air-sensitive and utilises aqueous hydrogen peroxide as oxidant. Extensive investigation of the influence of the reaction conditions such as solvent, temperature, copper salt and ligand was undertaken to lead to the optimised conditions. While the direct attachment of one aryl substituent to the sulfide is essential for efficient enantiocontrol, in the case of the second substituent the enantiocontol is dependent on the steric rather than electronic features of the substituent. Significantly, use of naphthyl-substituted sulfides results in excellent enantiocontrol; notably 97% ee, obtained in the oxidation of 2-naphthyl benzyl sulfide, represents the highest enantioselectivity reported to date for a copper-mediated sulfur oxidation. Some insight into the mechanistic features of the copper-mediated sulfur oxidation has been developed based on this work, although further investigation is required to establish the precise nature of the catalytic species responsible for asymmetric sulfur oxidation. Full experimental details, describing the synthesis and structural characterisation, and determination of enantiopurity are included in chapter 3.	en
dc.description.sponsorship	Irish Research Council for Science Engineering and Technology (EMBARK)	en
dc.description.status	Not peer reviewed	en
dc.description.version	Accepted Version
dc.format.mimetype	application/pdf	en
dc.identifier.citation	O’Mahony, G. E. 2013. Copper-catalysed asymmetric sulfide oxidation. Ph.D. Thesis, University College Cork.	en
dc.identifier.endpage	347
dc.identifier.uri	https://hdl.handle.net/10468/1173
dc.language.iso	en	en
dc.publisher	University College Cork	en
dc.rights	© 2013, Graham E. O'Mahony	en
dc.rights.uri	http://creativecommons.org/licenses/by-nc-nd/3.0/	en
dc.subject	Asymmetric oxidation	en
dc.subject	Asymmetric catalysis	en
dc.subject.lcsh	Copper.	en
dc.subject.lcsh	Sulfur--Oxidation.	en
dc.subject.lcsh	Asymmetric synthesis.	en
dc.subject.lcsh	Sulfoxides.	en
dc.thesis.opt-out	false	*
dc.title	Copper-catalysed asymmetric sulfide oxidation	en
dc.type	Doctoral thesis	en
dc.type.qualificationlevel	Doctoral	en
dc.type.qualificationname	PhD (Science)	en
ucc.workflow.supervisor	cora@ucc.ie	*

Copper-catalysed asymmetric sulfide oxidation

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