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  • Investigation of Chain Extension Approaches for the Stereoselective Reagent-Controlled Synthesis of alpha-Heteroatom Substituted Alkyl Boronic Esters

    Creator:
    Barsamian, Adam L.
    Abstract:
    Two distinct strategies were explored for the enantioselective synthesis of α-heteroatom substituted alkyl boronic esters by stereoselective reagent-controlled homologation using transient chiral carbenoid reagents CHYMX (Y = heteroatom, X = nucleofuge, M = electrofuge). In the first case, a stereospecific reagent-controlled homologation (sStReCH) approach to α-alkoxyalkylboronates using α-metalated S,O- and...
    Resource Type:
    Dissertation
    Full Text:
    Investigation of Chain Extension Approaches for the

  • Spectrophotometry of molybdenum, tungsten and chromium chelates of quercetin

    Creator:
    Mitchell, Lloyd James
    Abstract:
    Quercetin (3, 3', 4', 5, 7-pentahydroxyflavone) reacts with hexavalent molybdenum, tungsten and chromium to form chelates soluble in an ethanol-water medium. This color reaction has been investigated with a view to its possible application in the spectrophotometric determination of trace amounts of these metals. In the development of the method,...
    Resource Type:
    Dissertation
    Full Text:
    -quercetin chelate obeys Beer's law from O. 1 to 1. 8 ppm at 420 mµ where maximum absorbance occurs. The

  • Water and methanol adsorption on a series of organic complexes of montmorillonite

    Creator:
    Carter, Loren Sheldon
    Abstract:
    Water and methanol adsorption isotherms at 25° and 37° C. were determined on a series of organo-bentonite clays. The clays differed in the length of the carbon chain attached to the amine adsorbed in the cation exchange position. The amines used had carbon chains of 4, 6, 8, 10, 12,...
    Resource Type:
    Masters Thesis
    Full Text:
    about one millimeter extension per milligram of load. The isotherms were typical type II isotherms and

  • Thallous complexes in bromide solutions

    Creator:
    Dartau, Roland George
    Resource Type:
    Masters Thesis
    Full Text:
    heynolds and Argersinger (11, p. 418-.420), modified to allow its use in solutions of high ionic strength

  • Studying fusion reactions for effect of PCN on heavy nucleus formation and for nuclear structure effects

    Creator:
    Naik, Radhika
    Abstract:
    The fusion reaction ²⁰⁸Pb (⁵⁰Ti, xn) ²⁵⁸⁻x Rf (x = 1-3) was studied to determine PCN (probability that the mononucleus system evolves to form a compound nucleus inside the fission saddle point) and to establish the value of Wsur (survival probability) for the given reaction experimentally. The fission excitation function...
    Resource Type:
    Dissertation
    Full Text:
    larger than 2.5fm given by 1/30 AR × . This extension of the radius is attributed to the presence of

  • Development of Methods for Stereoselective Carbon-Carbon Bond Formation

    Creator:
    Wu, Zhenhua
    Abstract:
    Three distinct methods to achieve the stereoselective synthesis of carbon-carbon bonds were investigated, encompassing: (i) the formation of axially chiral biaryl molecules by enantioselective Suzuki cross-coupling, (ii) the synthesis of α-phenylalkylboronic esters by enantioselective chain extension, and (iii) the stereospecific synthesis of alkenes by eliminative cross-coupling of enantioenriched sp³-hybridized carbenoids....
    Resource Type:
    Dissertation
    Full Text:
    enantioselective chain extension, and (iii) the stereospecific synthesis of alkenes by eliminative cross-coupling

  • The normal vibrational analysis of polyacetaldehyde

    Creator:
    Lee, Dorothy
    Abstract:
    A method of calculating the normal vibrations of polymer molecules is presented in detail. The method is based on that used by Schachtschneider and Snyder in their analysis of polypropylene but has not heretofore been published. The factoring of the infinite matrix and reduction to the coordinates of the unit...
    Resource Type:
    Dissertation
    Full Text:
    rnolecules to rnake the extension to polyrner rnolecules by this rnethod. The geometry of polyrner chains

  • Stereospecific Synthesis of Stereotriad Motifs and Alkenes Using Enantioenriched sp³-Hybridized Carbenoids

    Creator:
    Xun, Sun
    Abstract:
    Enantioenriched sp³-hybridized carbenoid reagents CR1R2MX (X = nucleofuge, M = electrofuge) of different types were investigated for the synthesis of polysubstituted alkyl chains by iterative stereospecific reagent-controlled homologation (StReCH) and for the stereospecific connective synthesis of alkenes by eliminative cross-coupling. In the first part, putative enantioenriched α-chloroalkyllithiums (CHRLiCl) were employed...
    Resource Type:
    Dissertation
    Full Text:
    contiguous stereotriad motif were separately targeted by triple chain extension of B-phenethyl boronic

  • 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:
    require large π-conjugation extension and hence provides space for further chemical engineering for

  • The microstructure of marine sediments

    Creator:
    Stump, Arthur Darrell
    Abstract:
    The surface areas and pore size distributions of a series of terrigenous marine sediments were measured by gas adsorption. The sediment samples were taken from the continental terrace off the coast of Oregon near Newport. Sampling stations ranged up to 35 miles off shore between 44°20' and 45° north latitude....
    Resource Type:
    Dissertation
    Full Text:
    extension per mg load and with a capacity of 1+00 mg. The samples were contained in small buckets shaped