Show simple item record

dc.contributor.advisorWard, Dale E.en_US
dc.creatorJheengut, Vishalen_US
dc.date.accessioned2007-08-24T14:00:53Zen_US
dc.date.accessioned2013-01-04T04:54:13Z
dc.date.available2008-08-25T08:00:00Zen_US
dc.date.available2013-01-04T04:54:13Z
dc.date.created2007en_US
dc.date.issued2007en_US
dc.date.submitted2007en_US
dc.identifier.urihttp://hdl.handle.net/10388/etd-08242007-140053en_US
dc.description.abstractThe thiopyran route to polypropionates is an attractive strategy that involves a stepwise iterative aldol homologation of tetrahydro-4H-thiopyran-4-one (I) with thiopyran aldehyde (II) followed by desulfurization to rapidly assemble stereochemically complex polypropionate synthons. In chapter 1, the thesis is summarized in the context of relevant background research including; a) the basic principle of the thiopyran route; b) dynamic kinetic resolution of -substituted aldehydes; c) previous syntheses of serricornin; iv) previous syntheses of membrenones.In chapter 2, proline-catalyzed enantioselective direct intermolecular aldol reactions of tetrahydro-4H-thiopyran-4-one with various achiral aldehydes were studied. The results provided insights on the behaviour and stereoselectivity profile of thiopyranone (a crucial starting block in the thiopyran design) in the proline-catalyzed aldol reaction.In chapter 3, inspired by the results of the aldol reaction of ketone (I) with achiral aldehydes, we next investigated the proline-catalyzed asymmetric aldol reactions of (I) with racemic thiopyran aldehyde (II) as a strategy to rapidly prepare enantiomerically pure tetrapropionate synthons without any requirement of enantioenriched aldehyde. The reaction occurred with high enantiotopic group selectivity and dynamic kinetic resolution.In chapter 4, a detailed study to ascertain the scope and limitations of the design strategy described in chapter 3 was extended towards other catalysts, aldehydes and ketones. Finally, applications of the above mentioned strategy towards the synthesis of serricornin and membrenones A and B are elaborated in chapters 5 and 6 respectively.en_US
dc.language.isoen_USen_US
dc.subjectdynamic kinetic resolutionen_US
dc.subjectserricorninen_US
dc.subjectmembrenonesen_US
dc.subjectdouble stereodifferentiationen_US
dc.subjectdiastereotopicen_US
dc.subjecttetrazoleen_US
dc.subjectenantiotopicen_US
dc.subjectprolineen_US
dc.subjectaldolen_US
dc.subjectorganocatalysisen_US
dc.subjectcyclic sulfidesen_US
dc.subjectmutual kinetic enantioselectionen_US
dc.titleThiopyran route to polypropionates : proline catalyzed aldol reactions of tetrahydro-4H-thiopyran-4-oneen_US
thesis.degree.departmentChemistryen_US
thesis.degree.disciplineChemistryen_US
thesis.degree.grantorUniversity of Saskatchewanen_US
thesis.degree.levelDoctoralen_US
thesis.degree.nameDoctor of Philosophy (Ph.D.)en_US
dc.type.materialtexten_US
dc.type.genreThesisen_US


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record