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Filtering by: Creator O'Conner, Carl W. Remove constraint Creator: O'Conner, Carl W. Academic Affiliation Chemistry Remove constraint Academic Affiliation: Chemistry Committee Member Blakemore, Paul R. Remove constraint Committee Member: Blakemore, Paul R.

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  • A Diels-Alder approach to biaryl synthesis

    Creator:
    Ashburn, Bradley O.
    Abstract:
    An expedient approach to the synthesis of a wide range of highly programmable biaryl templates has been accomplished. Utilizing the Diels-Alder [4+2] cycloaddition, a wide range of tri- and tetra-ortho-substituted biaryls have been synthesized in only three to four steps from commercially available materials. We have successfully synthesized entire classes...
    Resource Type:
    Dissertation
    Full Text:
    AN ABSTRACT FOR THE DISSERTATION OF Bradley O. Ashburn for the degree of Doctor of Philosophy

  • Computational Investigation and Prediction of Mechanisms and Stereocontrol in Complex Organic Reactions

    Creator:
    Pattawong, Ommidala
    Abstract:
    Complex organic transformations, such as the addition of pyrrole to ketene using planar chiral organocatalyst (*PPY), the four-component anhydride- Manniach reactions, and the site-selective desymmetrization of meso-1,2-diol, are remarkable synthetic reactions that provide high yield and high selectivity. However, the exact mechanism and origins of stereocontrol for theses synthetic organic...
    Resource Type:
    Dissertation
    Full Text:
    CH···O interactions. The former differentiates the E/Z-catalyst enolates in the transition states

  • Dynamics and Design of Green Fluorescent Protein-Inspired Superphotoacids and Red-Emitting Fluorophores with Transient Absorption and Femtosecond Stimulated Raman Spectroscopy

    Creator:
    Chen, Cheng
    Abstract:
    In the past decades, femtosecond stimulated Raman spectroscopy (FSRS) has been gaining tremendous popularity in fundamental sciences stemming from chemistry to biology. It is capable of capturing both equilibrium and non-equilibrium structural information across a broad range of timescales with simultaneously high temporal and spectral resolutions. Femtosecond transient absorption spectroscopy...
    Resource Type:
    Dissertation
    Full Text:
    group (EDG) to the ortho site of the −OH/O− group of p-HBDI was discovered to destabilize the ground

  • Synthetic Studies towards Highly Oxygenated Furanyl Diterpenoids

    Creator:
    Goswami, Subir
    Abstract:
    The furanyl diterpenoid family of natural products has drawn the attention of both synthetic organic chemists and pharmacologists due to their complex structural architectures and diverse biological activity. Among them, wortmannin has been most extensively studied for biological activities. All these furanyl diterpenoids consist of a highly strained naptha[1,8-bc]furan core,...
    Resource Type:
    Dissertation
    Full Text:
    .; Oh, C.; Scheuer, P. J. J. Korean Chem. Soc. 1995, 39, 301-305. (e) Zhu, Y.; Yoshida, W. Y.; Kelly

  • Cis-2,5-diaminobicyclo[2.2.2]octane : a novel C₂-symmetric scaffold for asymmetric catalysis

    Creator:
    Shaw, Subrata
    Abstract:
    This thesis describes the development of a new enantioselective synthetic method employing chiral cis-2,5-diaminobicyclo[2.2.2]octane-based organometallic catalysts. The significance of this new method to organic synthesis is illustrated with preparation of enantioenriched products that are transformed to important pharmaceutical agents. Chapter 1 provides a brief historical overview of asymmetric catalysis, especially...
    Resource Type:
    Dissertation
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    38 Chapter 3. The Asymmetric Hetero-Diels-Alder Reaction 39 3.1 Introduction 39 3.2 Role of

  • Total synthesis of phorboxazole A

    Creator:
    Lee, Tae Hee
    Abstract:
    The total synthesis of a highly potent cytotoxic marine natural product, phorboxazole A, is described. Both a palladium(II)-mediated and a palladium(II)-catalyzed intramolecular alkoxycarbonylation were used as key steps for the preparation of the two cis-2,6-disubstituted tetrahydropyran rings (C22-C26 and C11-C15) of phorboxazole A. The synthesis used a convergent approach involving...
    Resource Type:
    Dissertation
    Full Text:
    , 3801. (n) Greer, P. B.; Donaldson, W. A. Tetrahedron 2002, 58, 6009. (o) White, J. D.; Kranemann, C. L

  • Part I: Synthetic studies toward the southern portion of Azaspiracid-1; Part II: Total synthesis of amphidinolide B₁ and the proposed structure of amphidinolide B₂

    Creator:
    Lu, Liang
    Abstract:
    The structural architecture present in marine toxin azaspiracid - 20 stereocenters, 9 rings, 3 separated spirocenters - has attracted considerable synthetic attention. Our efforts toward the synthesis of azaspiracid have led to the completion of both C₁-C₂₆ northern and C₂₇-C₄₀ southern halves. Herein, the synthesis of southern FGHI ring system...
    Resource Type:
    Dissertation
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    212224 27 1.4 1.5 1.6 1.7 1.8 O O 40 37 39 1.9 4 steps N3 O 373940 1.10 CHO O O 1.11 9

  • Studies toward the synthesis of halichlorine and pinnaic acid

    Creator:
    Korf, Eric A.
    Abstract:
    Three approaches toward the core of halichlorine and pinnaic acid are described. The first approach entails a racemic transannular nitrone-olefin [3+2] cycloaddition from nitrone 238. Construction of the nitrone 238 began with aldehyde 241. Another key feature in this route involved a ring-closing metathesis for the formation of a 14-membered...
    Resource Type:
    Dissertation
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    of halichlorine……..…….39 1.4.17. Ihara’s approach to the bicyclic core of halichlorine

  • A unified approach for the total synthesis of C₁₀-functionalyzed Lycopodium alkaloids

    Creator:
    Saha, Mrinmoy
    Abstract:
    Lycopodium alkaloids have shown widespread and noteworthy biological activity, consisting of over 250 known natural products. Moreover, their structural complexity and diversity have attracted considerable attention from numerous laboratories including our own. Recently, we have developed a unified approach that would provides access to numerous, previously unprepared C₁₀-functionalized lycopodium alkaloids....
    Resource Type:
    Dissertation
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    ), as they share similar skeleton to the eastern fragment of himeradine A. lycopodine (1.1) N O

  • Total Synthesis of Cephalotaxus Alkaloids and Synthetic Studies toward Bazzanin K

    Creator:
    Ju, Xuan
    Abstract:
    Dearomatization reactions exist broadly in biosynthesis and chemical synthesis. The highly functionalized atoms of arenes can be masked by it aromaticity, and upon dearomatization, those reactive atoms can be readily applied to bond formation and further manipulation. The total synthesis of (–)-cephalotaxine and (–)- homoharringtonine is described via an oxidative...
    Resource Type:
    Dissertation
    Full Text:
    CHO O H OEt 3) NaOEt, MeI 53%, >95% ee 79%, >95% ee c) d) e) f) OH 1) tBuOK, tBuOH 2) NaOMe