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Denmark, Scott E. Denmark, Scott E. Burke, Martin D. Donk, Wilfred v Rauchfuss, Thomas B. Kornfilt, David Jean Pierre 2017-03-01T16:37:00Z 2017-03-01T16:37:00Z 2019-03-02T10:15:14Z 2016-11-30 2016-12 The Lewis base activation of Lewis acids has been harnessed in the development of an enantioselective oxysulfenylation reaction for unactivated alkenes. The weak Lewis acid N-(phenylthio)-phthalimide can be activated in the presence of a moderate Brønsted acid and chiral Lewis base donors. The resulting complex is a powerful sulfenylating agent capable of sulfenium transfer to simple mono-, di- and trisubstituted alkenes with high selectivity to form enantioenriched thiiranium ions. Stereospecific and site-selective capture of the thiiranium ions furnish vicinally functionalized thioethers. The nucleophile scope of the reaction encompasses alcohols, carboxylic acids and phenols. Both inter- and intramolecular sulfenylation reactions were realized. The reaction is highly robust and individual substrates usually did not require reoptimization. Mechanistic, X-ray crystallographic and kinetic investigations enabled a complete catalytic cycle to be formulated. The proposed cycle was supported by both kinetic data and the characterization of reaction intermediates. The turnover-limiting and enantiodetermining steps were identified as thiiranium ion formation. X-ray crystallography of the active sulfenylating agent did not immediately identify a basis for the high selectivity. Instead, the origin of selectivity in the reaction of trans-alkenes was determined to be distortion-based with the aid of computational models. Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2018-12-01 The student, David Kornfilt, accepted the attached license on 2016-11-29 at 14:19. The student, David Kornfilt, submitted this Dissertation for approval on 2016-11-29 at 14:23. This Dissertation was approved for publication on 2016-11-30 at 12:50. DSpace SAF Submission Ingestion Package generated from Vireo submission #10354 on 2017-02-28 at 14:37:01 Made available in DSpace on 2017-03-01T16:37:00Z (GMT). No. of bitstreams: 4 KORNFILT-DISSERTATION-2016.pdf: 8766160 bytes, checksum: 6bbf71143466e4b185255678233d4c8f (MD5) KornfiltThesis3l.docx: 6346049 bytes, checksum: a076c3449f55b53e0a7b908b96d64519 (MD5) LICENSE.txt: 4211 bytes, checksum: e3533c0f31abbfe38d75567f4b01e9f3 (MD5) PROQUEST_LICENSE.txt: 4557 bytes, checksum: 9589c034d5c9c8f6b13d4091b89f1e93 (MD5) Previous issue date: 2016-11-30 Embargo set by: Seth Robbins for item 98609 Lift date: 2019-03-01T16:37:19Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system U of I Only Restriction Lifted for Item 98609 on 2019-03-02T10:15:14Z. application/pdf http://hdl.handle.net/2142/95493 en Copyright 2016 David Kornfilt Catalysis Lewis Bases Enantioselecive Organocatalysis Lewis base catalyzed enantioselective oxysulfenylation of alkenes text text Chemistry Chemistry University of Illinois at Urbana-Champaign Dissertation Ph.D.