Shared more. Cited more. Safe forever.
    • advanced search
    • submit works
    • about
    • help
    • contact us
    • login
    View Item 
    •   MOspace Home
    • University of Missouri-Columbia
    • Graduate Studies - Theses and Dissertations (MU)
    • Theses and Dissertations (MU)
    • Dissertations (MU)
    • 2007 Dissertations (MU)
    • 2007 MU dissertations - Freely available online
    • View Item
    •   MOspace Home
    • University of Missouri-Columbia
    • Graduate Studies - Theses and Dissertations (MU)
    • Theses and Dissertations (MU)
    • Dissertations (MU)
    • 2007 Dissertations (MU)
    • 2007 MU dissertations - Freely available online
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.
    advanced searchsubmit worksabouthelpcontact us

    Browse

    All of MOspaceCommunities & CollectionsDate IssuedAuthorAuthor/ContributorTitleSubjectIdentifierThesis DepartmentThesis AdvisorThesis SemesterThis CollectionDate IssuedAuthorAuthor/ContributorTitleSubjectIdentifierThesis DepartmentThesis AdvisorThesis Semester

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular AuthorsStatistics by Referrer

    Deantiaromatization as a driving force in an electrocyclization of cyclopentadienone and the total synthesis of 1-epi-esco-pseudopteroxazole

    Zheng, Pinguan, 1977-
    View/Open
    [PDF] public.pdf (6.963Kb)
    [PDF] short.pdf (259.9Kb)
    [PDF] research.pdf (6.704Mb)
    Date
    2007
    Format
    Thesis
    Metadata
    [+] Show full item record
    Abstract
    Deantiaromatization has been successfully demonstrated as a driving force in an electrocyclization of cyclopentadienones. The reaction was found to be general for a number of substrates and provides a unique way to access tricyclic ring systems with high stereoselectivity. Some evidence was uncovered to show that the process is indeed an 8 [pi] conrotatory electrocyclic ring closure. During the exploration of substituent effects in the electrocyclization, a novel coupling reaction of an organolithium with primary halides was discovered. The experimental data suggested the engagement of the silicon atom and the important role of terminal alkene in the coupling reaction. However, the application of thiw methodology to other silane systems was successful. The total synthesis of 1-epi-seco-pseudopteroxazole was accomplished in 17 steps, featuring the Buchwald-Hartwig coupling, a stereoselective intramolecular Michael reaction, a Heck coupling and asymmetric reduction of trisubstituted alkene. In the course of reductive cleavage of the C-I bond to access key intermediate 358, a novel dephenylation of Harmata benzothiazines was discovered to provide chiral cyclic sulfinamides with complete stereocontrol. Preliminary mechanistic studies were carried out and a plausible mechanism was proposed based on our experimental results.
    URI
    https://hdl.handle.net/10355/4669
    https://doi.org/10.32469/10355/4669
    Degree
    Ph. D.
    Thesis Department
    Chemistry (MU)
    Collections
    • 2007 MU dissertations - Freely available online
    • Chemistry electronic theses and dissertations (MU)

    Send Feedback
    hosted by University of Missouri Library Systems
     

     


    Send Feedback
    hosted by University of Missouri Library Systems