2026-09-21T08:33:38Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/121198 2023-12-11 col_2142_5131 col_2142_14789 com_2142_5130 com_2142_14788 com_2142_8903

Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2025-08-01 The student, Emily Mumford, accepted the attached license on 2023-05-26 at 13:41. The student, Emily Mumford, submitted this Dissertation for approval on 2023-05-26 at 14:34. This Dissertation was approved for publication on 2023-06-08 at 08:52. DSpace SAF Submission Ingestion Package generated from Vireo submission #19393 on 2023-12-04 at 17:30:24 Denmark, Scott E. Denmark, Scott E. van der Donk, Wilfred A. Mirica, Liviu M. Mehta, Angad P. 2023-08 application/pdf en text Selenium redox-catalyzed alkene syn-difunctionalization Mumford, Emily Millicent 2023-06-08 Alkene Difunctionalization Main Group Redox Catalysis Mechanism Oxazoline Imidazolidinone Selenium This thesis covers two projects both involving the use of selenium redox catalysis for alkene difunctionalization. It begins with a brief overview of the chemistry of electrophilic selenium reagents and their reactivity with alkenes to incorporate various nucleophiles in selenofunctionalization reactions. It then moves into examples where the incorporated selenide can be oxidized and displaced to give syn-dichlorination and syn-diamination products. In covering the state of the art in main group redox catalysis for alkene difunctionalization, comparisons are made to transformations accomplished using organoiodine redox catalysis. Chapter 2 covers the development of a high yielding and highly enantioselective alkene oxyamination reaction for the synthesis of 2-aryl oxazolines, based upon an existing strategy for alkene diamination. This oxyamination method uses N-tosyl benzamides in combination with alkene substrates, a chiral diselenide catalyst, and sym-collidinium fluoride tetrafluoroborate as an oxidant. Reaction discovery and optimization, alkene substrate scope, and transformation of the products to differentially protected amino alcohols as well as PHOX ligands are discussed. Mechanistic considerations of low-yielding substrates are addressed, and future directions including use of alkene oxyamination for the synthesis of additional classes of oxazoline-containing ligands are discussed. Chapter 3 covers efforts to elucidate the mechanism of the selenium redox-catalyzed syn¬-diamination reaction. Experiments towards mechanism determination included reaction profile determination through continuous reaction monitoring by 19F NMR, initial rate kinetics, assessment of any non-linear effects, probing for radical intermediates, evaluation of isolable species of reactions at partial conversion, and attempted syntheses of postulated intermediates along the proposed catalytic cycle. Along the way, the effects of reaction parameters including concentration, identity of solvent, urea nucleophile, oxidant, and diselenide were evaluated. Text eng https://hdl.handle.net/2142/121198 Copyright 2023 Emily Mumford Ph.D. Dissertation Chemistry University of Illinois at Urbana-Champaign Chemistry