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Wendell Willkie, a Hoosier liberalThompson, Sarah Chapman 03 June 2011 (has links)
At various intervals there have appeared on the American scene unique individuals whose ideals and principles have shaped the course of American history and the destiny of the American people. More often than not, they have appeared, as if providentially, in times of stress and turmoil, or at the least, during periods that were particularly decisive to the nation's history.Such individuals have always had certain characteristics in common. They were men of integrity and principle. They had a deep and abiding love for their country and an unfaltering faith in her future under a democratic system of government. They were men of vision whose ideas were usually far ahead of the times in which they lived. And they were not content merely to espouse their particular principles in theory alone, they also had the necessary devotion to duty to work tirelessly to make those ideals a reality, and the courage and fortitude to remain constant in the face of the adversity which they encountered in the process. Most of them had an empathy for the common man which transcended the normal sphere of interpersonal relationships and elevated it to the plane which recognizes the human kinship and brotherhood of all men. And finally, all of them left a legacy of ideas which are universally viable, and which serve as a constant source for the renewal of those ideals which are the foundation and supporting strength of the nation.In the days when the Republic was new, America was fortunate in having more than a few men of this caliber--men like Thomas Jefferson, James Madison, Alexander Hamilton. And later, at decisive moments when the need was great, other men like Abraham Lincoln, Theodore Roosevelt, and Woodrow Wilson arose to lead their country and to plead the cause of liberalism and humanitarianism. Wendell Willkie was another such man. He believed in the integrity and worth of the individual, in his right to the basic human freedoms regardless of race, creed, or color, and in the ability of an enlightened citizenry to govern itself politically under a democratic system of government, and economically under the free-enterprise system.His contributions reflected these basic beliefs. At home he strove to lift American politics out of the realm of narrow, petty partisanship and expediency, and to elevate it to a system, regulated by high moral conduct, which would be responsive to the needs of the American people. In a broader sense, he fought imperialism both at home and abroad by working to establish those civil liberties which guarantee freedom, equal opportunity, and dignity to all human beings. He worked to rally the free world against the perils of a totalitarianism which threatened to destroy that freedom, and above all, to rally it in support of a system of international cooperation which not only would keep world peace, but also provide a forum where the brotherhood of man could become a reality.It is the purpose of this dissertation to examine the principles and ideals which guided Wendell Willkie's thinking and motivated his actions, to note the nineteenth-century background which fostered them, to follow the active crusade he made in their behalf, and finally, to summarize briefly the contribution of those ideals and principles to the American democratic system and to the concept of "one world."
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Transition Metal Complexes and Main Group Frustrated Lewis Pairs for Stoichiometric and Catalytic P-P and H-H Bond ActivationGeier, Stephen 15 February 2011 (has links)
Stoichiometric and catalytic small molecule activation reactions are vital for the synthesis of new materials. The activation of phosphorus-hydrogen or phosphorus-phosphorus bonds allows for the facile synthesis of new phosphorus-containing molecules for a wide variety of applications.1
An investigation of the P-H dehydrocoupling reaction was undertaken utilizing two rhodium(I) based catalysts. Over the course of this investigation it was found that the Rh(I) systems were also active catalysts for the reverse reaction: phosphorus-phosphorus bond hydrogenation (and hydrosilylation). This reaction was exploited for the synthesis of novel phosphines from P-P bound species. Molecules with P-P bonds were reacted in a stoichiometric fashion with the catalyst precursor, producing a variety of novel species with interesting bonding features which shed some light on the reaction mechanism.
Following the discovery in 2006 that a linked phosphine-borane system could reversibly activate hydrogen2 a tremendous effort has been put forth to understand and expand this unprecedented reactivity.3,4 This new archetype for metal-free small molecule activation, containing a bulky Lewis acid and Lewis base which are unable to bond directly due to steric repulsion, has been termed a “frustrated Lewis pair” (FLP).3,4
The FLP concept is expanded to include bulky P-P bound species, pyridines and P-O bound Lewis bases as partners for B(C6F5)3. In some cases small molecule activation produced ion pairs or zwitterions related to those found for reactions with tertiary phosphines,3,4 but in others novel reaction pathways were discovered including phosphorus-phosphorus bond cleavage, catalytic hydrogenations and the formation of novel intramolecular FLPs. An unexpected situation was observed for the pair of 2,6-lutidine with B(C6F5)3, where adduct formation was observed along with free Lewis acid and base, but H2 activation by the FLP proceeded smoothly.
Covalently bound phosphinoboranes of the general formula R2PB(C6F5)2 are synthesized. While systems with small R groups dimerized, monomers existed for cases with bulkier R groups. These monomers were found to exhibit extraordinarily short phosphorus-boron bonds yet were still capable of H2 activation analogous to bimolecular phosphine-borane systems. These systems also showed unique reactivity with Lewis acids and Lewis bases.
This work further demonstrates the broad and general utility of the FLP concept in the synthesis of new materials and in catalytic transformations.
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Heavy atom induced phosphorescence of organic materials using mono- and trifunctional organomercury derivativesBurress, Charlotte Nicole 15 May 2009 (has links)
This dissertation focuses on the phosphorescence of organic chromophores using
perfluoro-ortho-phenylene mercury (1) and bis(pentafluorophenyl)mercury (2) as
external heavy atom effect inducers. To ascertain the suitability of these luminescent
adducts for OLED applications, several research objectives have been investigated.
To further shorten the triplet lifetimes of adducts involving 1, a strategy was
developed which combines both internal and external heavy atom effects. Specifically,
complexes involving 1 and N-methylcarbazole, N-methylindole and the 1-
halonaphthalenes were investigated. The existence and stability of the complexes could
be confirmed in solution by fluorescence spectroscopy. In the solid state, these adducts
form supramolecular binary stacks where the molecules of 1 alternate with the aromatic
substrate. As a result of the mercury external heavy atom effect, all of these adducts
display intense room temperature phosphorescence of the free arene. With the Nheterocycles,
the triplet lifetimes were drastically reduced to below 100 mu-s.
To appreciate the origin of the unusual heavy atom effects observed in arene
adducts with 1, 2 was studied as a monofunctional analog to 1. By utilizing fluorescence
spectroscopy, naphthalene, biphenyl, and fluorene complexes of 1 and 2 have been
detected in solution. The solid state structure of the adducts with 2 reveal
supramolecular binary stacks. Comparison of the photophysical results supports the
occurrence of cooperative effects between the Lewis acidic mercury centers of 1, which
make it a more efficient external heavy-atom effect inducer. Polymeric materials which are amenable to deposition in thin layers were
investigated as substrates for 1 and 2. Both poly(vinyl-2-naphthalene) and
poly(vinylcarbazole) interact with 1 and 2 in solution as evidenced by fluorescence
spectroscopy. With the solid blend 1•PVK, a small doping percentage of 1 results in
white emission, while larger percentages of 1 yield bright orange emission.
This dissertation presents the first structurally characterized ternary complex with
1, carbazole, and coordinating solvents THF and triethylamine. IR spectroscopy and
short N···O and N···N distances in the solid state indicates that the acidic N-H moiety of
carbazole interacts with the solvent by hydrogen bonding. In the extended structure,
molecules of 1 and the hydrogen bonded complex alternate to form supramolecules.
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Neutral and Cationic Main Group Lewis Acids - Synthesis, Characterization and Anion ComplexationHudnall, Todd W. 14 January 2010 (has links)
The molecular recognition of fluoride and cyanide anions has become an
increasingly pertinent objective in research due to the toxicity associated with these
anions, as well as their widespread use. Fluoride is commonly added to drinking water
and toothpastes to promote dental health, and often used in the treatment of osteoporosis,
however, high doses can lead to skeletal fluorosis, an incurable condition. Cyanide is
also an extremely toxic anion, which binds to and deactivates the cytochrome-c oxidase
enzyme, often leading to fatality. The molecular recognition of these anions in water has
proven to be challenging. For fluoride, the anion is small, and thus, efficiently hydrated
(?H�hyd = -504 KJ/mol), making its complexation in aqueous environments particularly
difficult. In addition to being small and efficiently hydrated like the fluoride anion,
cyanide has a pKa(HCN) of 9.3 making its competing protonation in neutral water a further
complication. Recent efforts to complex fluoride and cyanide have utilized
triarylboranes, which covalently bind the anion. Monofunctional triarylboranes display
a high affinity for fluoride with binding constants in the range of 105-106 M-1 in organic
solvents, and chelating triarylboranes exhibit markedly higher anion affinities. These
species, however, remain challenged in the presence of water.
This dissertation focuses on the synthesis and properties of novel Lewis acids
designed for the molecular recognition of fluoride or cyanide in aqueous environments.
To this end, a group 15 element will be incorporated into a main group Lewis acidcontaining
molecule for the purpose of: i) increasing the Lewis acidity of the molecule
via incorporation of a cationic group, and ii) increasing the water compatibility of the
host. Specifically, a pair of isomeric ammonium boranes has been synthesized. These
boranes are selective sensors which selectively bind either fluoride or cyanide anions in water. The study of phosphonium boranes has revealed that the latent Lewis acidity of
the phosphonium moiety is capable of aiding triarylboranes in the chelation of small
anions. Finally, my research shows that Br�nsted acidic H-bond donors such as amides,
when paired with triarylboranes, are capable of forming chelate complexes with fluoride.
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Synthesis,structures and reactivities of bis(triarylmethylium) dications and related diboranesWang, Huadong 01 November 2005 (has links)
The primary goal of the research described in this thesis concern the synthesis,
characterization and study of 1,8-bis(diarylmethylium)naphthalenediyl dications. Such
dications have been prepared from the corresponding diols and have been fully
characterized. Single crystals X-ray diffraction studies indicate that the two cationic
centers of these derivatives are separated by 3.0 - 3.1 ??. The enforced proximity of the
cationic centers intensifies the electron deficiency of these derivatives which behave as
strong organic oxidants. As indicated by cyclic voltammetry, these dications undergo a
two-electron reduction to afford the corresponding acenaphthenes. The newly formed
C-C bond which links the former methylium are remarkably long (1.628-1.706 ??.) and
can, in some instances, be oxidatively cleaved in the presence of acids. These dications
can also be reduced chemically by reducing reagent, such as hydride, chloride, bromide
and iodide. Remarkably, the reaction of 1,8-bis(diphenylmethylium)naphthalenediyl
dication with fluoride anion results in the formation of a mono fluorinated cation which
features an unsymmetrical C-F?C bridge between the former methylium centers. As
indicated by 1H NMR spectroscopy, the structure of this cation is fluxional with the fluorine atom oscillating between the former methylium centers. Finally, this thesis also
deals with the synthesis and study of 4,6-bis(dimesitylboryl)dibenzofuran and
isoelectronic dications.
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Development of Lewis Base Catalyzed Stereoselective Methods for Synthesis of Beta- Lactones and Dyotropic Rearrangements of Tricyclic Beta-Lactones.Purohit, Vikram C. 14 January 2010 (has links)
The recent finding that the FDA-approved antiobesity agent orlistat (tetrahydrolipstatin, Xenical) is a potent inhibitor of the thioesterase domain of fatty acid synthase (FAS) led us to develop a concise and practical asymmetric route to
pseudosymmetric 3,4-dialkyl-cis-beta-lactones. The well-documented upregulation of FAS
in cancer cells makes this enzyme complex an interesting therapeutic target for cancer.
The described route to 3,4-dialkyl- beta -lactones is based on a two-step process involving Calter's catalytic, asymmetric ketene dimerization of acid chlorides followed by a facialselective hydrogenation leading to cis-substituted- beta -lactones. Importantly, the ketene dimer intermediates were found to be stable to flash chromatography, enabling
opportunities for subsequent transformations of these optically active, reactive
intermediates. Subsequent R-epimerization and R-alkylation or acylation led to trans- beta -
lactones and beta -lactones bearing alpha-quaternary carbons, respectively. Several of the ketene dimers and beta-lactones displayed antagonistic activity (apparent Ki in the low micromolar range) in competition with a fluorogenic substrate toward a recombinant
form of the thioesterase domain of fatty acid synthase. The best antagonist, a simple
phenyl-substituted cis- beta -lactone, displayed an apparent Ki (2.5 ( 0.5 muM) of only 10- fold lower than that of orlistat (0.28 ( 0.06 muM). In addition, mechanistic studies of the ketene dimerization process by Reaction View infrared spectroscopy support previous findings that ketene formation is rate determining. A highly diastereoselective, nucleophile-promoted bis-cyclization process,
employing readily available and tractable keto-acid substrates, is described. This
methodology provides concise access to bicyclic- and tricyclic-beta-lactones bearing
tertiary carbinol centers and quaternary carbons, greatly extending the scope of previous routes to bicyclic-beta-lactones from aldehyde acid substrates. This and related processes may be revealing a subtle interplay between [2 plus 2] cycloaddition and nucleophilecatalyzed aldol lactonization (NCAL) reaction manifolds. An early induction period in the bis-cyclization of keto-acids is confirmed via isolation of the complex between 4- pyrrolopyridine and Modified Mukaiyama reagent N-propyl-2-bromo pyridinium triflate.
Dyotropic rearrangements of tricyclic keto beta-lactones derived in high yields and
>19:1 diastereoselectivity from readily available 1, 3-dione acids is described. Zn (II) salts were found to be most efficient for affecting dyotropic 1, 2-acyl migrations where
as sub stoichiometric TMSOTf was found to execute a delta-lactone migration providing bis
gamma-lactone in modest yields. Enantioselective desymmetrization with inexpensive (S) - tetramisole has been demonstrated to provide direct evidence of Lewis base involvement in the Nucleophile Promoted Bis-cyclization of keto-acids. Further studies using TsCl as the carboxylate activating agent instead of modified Mukaiyama reagent and catalytic tetramisole are described for achieving practical, catalytic, enantioselective synthesis of beta-lactones from keto-acids. Preliminary studies toward conjugate addition- lactonization pathway provided a hint as to the complexity involved to affect this transformation under the bis-cyclization conditions. An alternate hypotheses concerning the possibility of isomerization-dienolate formation - lactonization is experimentally proven. Additionally, applications of these
and related findings in the intramolecular Morita-Baylis-Hillman reaction with cyclic
ketones have been investigated which provide new avenues of synthetic methodology
development.
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Nationalism and political liberty : Redlich, Namier, and the crisis of empire /Ng, Amy. January 1900 (has links)
Texte fondé sur: Dissertation--University of Oxford. / Bibliogr. p. 217-230.
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Synthesis and characterization of Lewis acidic aluminum and gallium complexes /Kingsley, Nicholas Bruck. January 2009 (has links)
Thesis (Ph. D.)--University of Toledo, 2009. / Typescript. "Submitted as a partial fulfillment of the requirements for the Doctor of Philosophy Degree in Chemistry." Includes bibliographical references (leaves 123-132).
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Adventures in group 13 chemistry /Silverman, Joel Samuel, January 1999 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references. Available also in a digital version from Dissertation Abstracts.
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The Federal Theatre Project fractured national identity and the silencing of America's only national theatre: with a special look at Sinclair Lewis's It can't happen here /Monroe, Rebecca A. January 1996 (has links)
Thesis (M.A.)--Kutztown University, 1996. / Source: Masters Abstracts International, Volume: 45-06, page: 2834. Typescript. Includes bibliographical references (leaves 86-92).
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