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dc.contributor.advisorAlexander T. Radosevich.en_US
dc.contributor.authorDummit, Krysta A.(Krysta Alanna)en_US
dc.contributor.otherMassachusetts Institute of Technology. Department of Chemistry.en_US
dc.date.accessioned2021-01-06T20:16:32Z
dc.date.available2021-01-06T20:16:32Z
dc.date.copyright2020en_US
dc.date.issued2020en_US
dc.identifier.urihttps://hdl.handle.net/1721.1/129287
dc.descriptionThesis: Ph. D., Massachusetts Institute of Technology, Department of Chemistry, September, 2020en_US
dc.descriptionCataloged from student-submitted PDF of thesis.en_US
dc.descriptionIncludes bibliographical references.en_US
dc.description.abstractFirst, the development of a novel C-H amination strategy using both a Cu(II) Lewis acid and an organic hydrogen atom transfer (HAT) catalyst to activate benzylic C-H bonds adjacent to aromatic azaheterocycles is described. This simple method demonstrates very high selectivity towards aromatic azaheterocycles without using exogenous directing groups and affords excellent site selectivity in substrates with more than one reactive position. A wide range of aromatic azaheterocyclic structures not compatible with previously reported catalytic systems have proven to be amenable to this approach. Mechanistic investigations indicate a possible radical-mediated H-atom abstraction for select substrates, which would stand in contrast to known closed-shell Lewis acid catalyzed processes. Second, the synthesis and analysis of a series of three homologous [alpha],[alpha],[alpha]',[alpha]'-tetramethyl-[subscript 1]-phenylphosphacycles in order to investigate the theory that 4-membered ring phosphacycles - phosphetanes - are maximally biphilic as a result of bond angle compression that minimizes the HOMO-LUMO gap is reported. Analysis of [superscript 31]P NMR principal components validates the decrease in HOMO-LUMO gap as the intra-ring bond angle is compressed in the synthesized series as predicted by TD-DFT computations; however, ¹J[subscript P-Se] coupling constants, cyclic voltammograms and UV-Vis measurements are less conclusive. Computational modeling of the (3+1) cheletropic addition of the phosphacycles to nitrobiphenyl as a measure of the biphilicity reveals relative activation barriers within computational error for all but the smallest ring, indicating that the effect of intra-ring bond angle compression on phosphorus biphilic reactivity is a generally subtle effect.en_US
dc.description.statementofresponsibilityby Krysta A. Dummit.en_US
dc.format.extent305 pagesen_US
dc.language.isoengen_US
dc.publisherMassachusetts Institute of Technologyen_US
dc.rightsMIT theses may be protected by copyright. Please reuse MIT thesis content according to the MIT Libraries Permissions Policy, which is available through the URL provided.en_US
dc.rights.urihttp://dspace.mit.edu/handle/1721.1/7582en_US
dc.subjectChemistry.en_US
dc.titleStudies in duality : discovering a dual catalytic amination reaction and investigating the origin of biphilicity in phosphacyclesen_US
dc.title.alternativeDiscovering a dual catalytic amination reaction and investigating the origin of biphilicity in phosphacyclesen_US
dc.typeThesisen_US
dc.description.degreePh. D.en_US
dc.contributor.departmentMassachusetts Institute of Technology. Department of Chemistryen_US
dc.identifier.oclc1227521794en_US
dc.description.collectionPh.D. Massachusetts Institute of Technology, Department of Chemistryen_US
dspace.imported2021-01-06T20:16:31Zen_US
mit.thesis.degreeDoctoralen_US
mit.thesis.departmentChemen_US


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