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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Snow Flakes

Glaser, Michael 22 March 2007 (has links)
No description available.
32

The Synthesis of Benzyloxy Substituted DP-PPV and Examination of the Horner-Wadsworth-Emmons Reaction in the Synthesis of DP-PPV

Lear, Jeremy M. 04 June 2014 (has links)
No description available.
33

The Use of the Bible in Longfellow's Poetry

Turner, Ellen Howard 01 1900 (has links)
This thesis presents a brief biography of the American poet Henry Wadsworth Longfellow, then follows with a discussion of the influence of the Bible in Longfellow's poetry.
34

Nukleofilní zavedení fluorovaných funkčních skupin pomocí organofosforových sloučenin. / Nucleophilic introduction of fluorinated functional groups using organophosphorus compounds.

Opekar, Stanislav January 2014 (has links)
In the Introduction part of this thesis, the chemistry of organofluorine compounds is discussed, particularly the methods for the preparation of organofluorine compounds mainly by fluoroalkylation methods. Furthermore, the chemistry of fluorinated phosphonates, methods of their preparation, reactivity and biological activity is discussed. Additionally, the reactivity of fluoromethane derivatives is briefly mentioned and especially, the reactivity of diethyl fluoromalonate and fluorobisfenylsulfonylmethane is described. The Results and discussion part is devoted to the reactivity of three fluorinated phosphonates: tetraethyl fluoromethylenbisphosphonate, diethyl fluorophenylsulfonylphosphonate and previously not described diethyl fluoronitromethylphosphonate. These fluorinated phosphonates belong to the family of nucleophilic monofluoroalkylation reagents, meaning that these compounds are convenient starting materials for the synthesis of complex organic molecules containing the fluorine atom. The results deal with the reactivity of above mentioned fluorinated phosphonates, mainly with alkylation reactions, Horner-Wadsworth-Emmons reactions and conjugated additions. Also, other synthetic methods such as the Mitsunobu reaction or the palladium catalyzed allylation reaction were investigated; however,...
35

Glimpses of her Father's glory : deification and divine light in Longfellow's Evangeline

Bartel, Timothy E. January 2013 (has links)
In this thesis I endeavor to discover and show the Unitarian and Patristic theological influences on Henry Wadsworth Longfellow's long narrative poem Evangeline, with special focus on the poem's theological teachings concerning deification and descriptions of the spiritual experience of shining with divine light. In chapter one, I explore the theological climate of early nineteenth-century New England, focusing on the Unitarian and Transcendental movements and Longfellow's familiarity with both. In chapter two, I present an overview of the critical literature concerning the religious elements of Evangeline, beginning with reviews by Longfellow's contemporaries and ending with recent scholarship that calls for a new investigation of Unitarian influences on Evangeline. In chapters three and four, I look back to those Church Fathers who articulated the doctrines of deification and divine light in the second through fourth centuries. Through looking at the presence of the Church Fathers in Longfellow's writings, especially in the unexplored “Christian Fathers” manuscript lectures from the early 1830s, I show how the Patristic writers proved interesting and inspiring to Longfellow in the years leading up to the publication of Evangeline. Finally, in chapters five and six, I investigate in depth the religious elements of Evangeline, giving special attention to the keynote passages of 2.1 and 2.5, which include, respectively, theological teaching concerning deification and a description of the spiritual experience of shining with divine light. I conclude that though in 2.1 Longfellow articulates theological teachings that possess strong affinities with Unitarian doctrine, in 2.5 Longfellow concludes the poem with a characteristically Patristic vision of the deified heroine shining with divine light.
36

Canon and corpus: The making of American poetry / Making of American poetry

Upton, Corbett Earl, 1970- 12 1900 (has links)
viii, 233 p. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / This dissertation argues that certain iconic poems have shaped the canon of American poetry. Not merely "canonical" in the usual sense, iconic poems enjoy a special cultural sanction and influence; they have become discourses themselves, generating our notions about American poetry. By "iconic" I mean extraordinarily famous works like Henry Wadsworth Longfellow's "Paul Revere's Ride," Walt Whitman's "Song of Myself," and Claude McKay's "If We Must Die," that do not merely reside in the national memory but that have determined each poet's reception and thus have shaped the history of American poetry. Through case studies, I examine longstanding assumptions about these poets and the literary histories and myths surrounding their legendary texts. In carefully historicized readings of these and other iconic poems, I elucidate the pressure a single poem can exert on a poet's reputation and on American poetry broadly. I study the iconic poem in the context of the poet's corpus to demonstrate its role within the poet's oeuvre and the role assigned to it by canon makers. By tracing a poem's reception, I aim to identify the national, periodic, political, and formal boundaries these poems enforce and the distortions they create. Because iconic poems often direct and justify our inclusions and exclusions, they are of particular use in clarifying persistent obstacles to the canon reformation work of the last thirty years. While anthologies have become more inclusive in their selections and self-conscious about their ideological motives, many of the practices regarding individual poets and poems have remained unchanged over the last fifty years. Even as we include more poets in the canon, we often ironically do so by isolating a particular portion of the career, impulse in the work, or even a single poem, narrowing rather than expanding the horizon of our national literature. Through close readings situated in historical and cultural contexts, I illustrate the varying effects of iconic poems on the poet, other poems, and literary history. / Committee in charge: Dr. Karen J. Ford, Chair; Dr. John T. Gage, Member; Dr. Ernesto J. Martinez, Member; Dr. Leah W. Middlebrook, Outside Member
37

Síntese de Penta-2,4-dienonitrilas e 2-Cianometileno-but-3-enoatos de Etila via Olefinação de Horner-Wadsworth-Emmons e sua Aplicação na Obtenção de 4-Trifluormetil-piridin-2(1H)-iminas Substituídas e 2H-Piran-2-onas Análogas . / "Synthesis of Penta-2,4-dienenitriles and Ethyl 2-Cyanomethylene-but-3- enoates via Horner-Wadsworth-Emmons olefination and their Application to Obtaining Substituted 4-Trifluoromethyl-pyridin-2(1H)-imines and 2H-Pyran-2- ones Analog".

Bencke, Carlos Eduardo 26 March 2013 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / This paper presents the Horner-Wadsworth-Emmons olefination applied to preparing 22 new 5-alkoxy-3-trifluoromethyl-penta-2,4-dienenitriles (5), 5- phenylthio-3-trifluoromethyl-penta-2,4-dienenitriles (6) and ethyl 4-alkoxy-2- cyanomethylene-but-3-enoates (7) from the condensation between diethyl cyanomethylphosphonate (4) and β-alkoxyvinyl ketones (1), β-phenyltiovinyl ketones (2) and ethyl 4-alkoxy-2-oxo-but-3-enoates (3), furnishing the desired products with 10 to 93% yields. In a second step, this paper presents a simple and accessible novel synthetic route, for the preparation of a series of 30 unpublished 1,6- disubstituted 4-trifluoromethyl-pyridin-2(1H)-imines (14-19) from the condensation reaction of 5-aryl-3-trifluoromethyl-5-methoxy-penta-2,4- dienenitriles (Ar = Ph, 4-F-C6H4, 4-Br-C6H4, 4-Me-C6H4 and 4-MeO-C6H4) (5) with primary amines R-NH2 (R = Bu, 2-(1-cyclehexenil)ethyl, 2-(4- morpholinyl)ethyl, 2-phenethyl-ethyl, 2-(4-chlorophenethyl)ethyl and 2-(4- methoxyphenethyl)ethyl) (8-13), in a solvent free sealed system to give the expected products with yields between 20 to 98%. In addition, a series of new 6-substituted 4-trifluoromethyl-2H-pyran-2- ones (20) was obtained in 88 to 100% yeld, from the autocondensation reaction of 5-aryl-3-trifluoromethyl-5-methoxy-penta-2,4-dienenitriles (Ar = Ph, 4-F-C6H4, 4-Br-C6H4, 4-Me-C6H4 and 4-MeO-C6H4) (5), in a reflux system using water as solvent in the presence of HCl and 1 equivalent of ZnBr2. The pyridinimines, pyranones and dienes obtained in this work were identified and characterized by Hydrogen Nuclear Magnetic Resonance (H1NMR), Carbon-13 Nuclear Magnetic Resonance (C13 NMR), Mass Spectroscopy (GC-MS-EI), High Resolution Mass Spectroscopy (HRMS-ESI) and Elemental Analysis. / Este trabalho apresenta a metodologia de olefinação Horner-Wadsworth- Emmons aplicada de maneira inédita na preparação de 22 novas 5-alcóxi-3- trifluormetil-penta-2,4-dienonitrilas (5), 5-feniltio-3-trifluormetil-penta-2,4- dienonitrilas (6) e 4-alcóxi-2-cianometileno-but-3-enoato de etila (7) a partir da reação entre cianometilfosfonato de dietila (4) e respectivas β-alcoxivinil cetonas (1), β-feniltiovinil cetonas (2) e 4-alcóxi-2-oxo-but-3-enoatos de etila (3), levando a formação dos produtos com rendimentos entre 10 e 93%. Numa segunda etapa, este trabalho apresenta uma nova rota sintética, simples e acessível, para a preparação de uma série de 30 inéditas 4- trifluormetil-piridin-2(1H)-iminas 1,6-dissubstituídas (14-19) a partir da reação de condensação entre os 5-aril-3-trifluormetil-5-metóxi-penta-2,4-dienonitrilas (Ar = Ph, 4-F-C6H4, 4-Br-C6H4, 4-Me-C6H4 e 4-MeO-C6H4) (5) com aminas primárias R-NH2 (R = Bu, 2-(1-cicloexenil)etila, 2-(4-morfolinil)etila, 2-fenetiletila, 2-(4-clorofenetil)etila e 2-(4-metoxifenetil)etila) (8-12), em um sistema fechado e sem solvente, obtendo os produtos esperados com rendimentos de entre 20 e 98%. Em outra etapa do trabalho, foram obtidas 4-trifluormetil-2H-piran-2-onas 6-substituídas (20) a partir da reação autocondensação de 5-aril-3-trifluormetil- 5-metóxi-penta-2,4-dienonitrilas (Ar = Ph, 4-F-C6H4, 4-Br-C6H4, 4-Me-C6H4 e 4- MeO-C6H4) (5), em um sistema de refluxo utilizando água como solvente, na presença de HCl e 1 equivalente de ZnBr2, obtendo-se os produtos esperados com rendimentos entre 88 e 100%.As piridiniminas, piranonas e dienos obtidos neste trabalho foram identificados e caracterizados por Ressonância Magnética Nuclear de Hidrogênio (RMN H1), Ressonância Magnética Nuclear de Carbono-13 (RMN C13), Espectroscopia de Massas (CG-MS-EI), Espectroscopia de Massas de Alta Resolução (HRMS-ESI) e Análise Elementar.
38

Synthesis of Vinylene-Linked Two-Dimensional Conjugated Polymers via the Horner–Wadsworth–Emmons Reaction

Pastoetter, Dominik L., Xu, Shunqi, Borrelli, Mino, Addicoat, Matthew, Biswal, Bishnu P., Paasch, Silvia, Dianat, Arezoo, Thomas, Heidi, Berger, Reinhard, Reineke, Sebastian, Brunner, Eike, Cuniberti, Gianaurelio, Richter, Marcus, Feng, Xinliang 21 May 2024 (has links)
In this work, we demonstrate the first synthesis of vinylene-linked 2D CPs, namely, 2D poly(phenylenequinoxalinevinylene)s 2D-PPQV1 and 2D-PPQV2, via the Horner–Wadsworth–Emmons (HWE) reaction of C2-symmetric 1,4-bis(diethylphosphonomethyl)benzene or 4,4′-bis(diethylphosphonomethyl)biphenyl with C3-symmetric 2,3,8,9,14,15-hexa(4-formylphenyl)diquinoxalino[2,3-a:2′,3′-c]phenazine as monomers. Density functional theory (DFT) simulations unveil the crucial role of the initial reversible C−C single bond formation for the synthesis of crystalline 2D CPs. Powder X-ray diffraction (PXRD) studies and nitrogen adsorption-desorption measurements demonstrate the formation of proclaimed crystalline, dual-pore structures with surface areas of up to 440 m2 g−1. More importantly, the optoelectronic properties of the obtained 2D-PPQV1 (Eg=2.2 eV) and 2D-PPQV2 (Eg=2.2 eV) are compared with those of cyano-vinylene-linked 2D-CN-PPQV1 (Eg=2.4 eV) produced by the Knoevenagel reaction and imine-linked 2D COF analog (2D-C=N-PPQV1, Eg=2.3 eV), unambiguously proving the superior conjugation of the vinylene-linked 2D CPs using the HWE reaction.
39

Control of Crystallinity of Vinylene-Linked Two-Dimensional Conjugated Polymers by Rational Monomer Design

Pastoetter, Dominik L., Liu, Yannan, Addicoat, Matthew A., Paasch, Silvia, Dianat, Arezoo, Bodesheim, David, Waentig, Albrecht L., Xu, Shunqi, Borrelli, Mino, Croy, Alexander, Richter, Marcus, Brunner, Eike, Cuniberti, Gianaurelio, Feng, Xinliang 04 June 2024 (has links)
The interest in two-dimensional conjugated polymers (2D CPs) has increased significantly in recent years. In particular, vinylene-linked 2D CPs with fully in-plane sp2-carbon-conjugated structures, high thermal and chemical stability, have become the focus of attention. Although the Horner-Wadsworth-Emmons (HWE) reaction has been recently demonstrated in synthesizing vinylene-linked 2D CPs, it remains largely unexplored due to the challenge in synthesis. In this work, we reveal the control of crystallinity of 2D CPs during the solvothermal synthesis of 2D-poly(phenylene-quinoxaline-vinylene)s (2D-PPQVs) and 2D-poly(phenylene-vinylene)s through the HWE polycondensation. The employment of fluorinated phosphonates and rigid aldehyde building blocks is demonstrated as crucial factors in enhancing the crystallinity of the obtained 2D CPs. Density functional theory (DFT) calculations reveal the critical role of the fluorinated phosphonate in enhancing the reversibility of the (semi)reversible C−C single bond formation.
40

Methods for Asymmetric Olefination Reactions; Development and Application to Natural Product Synthesis

Strand, Daniel January 2006 (has links)
This thesis deals with the development and application of methods for asymmetric olefinations, in particular Horner-Wadsworth-Emmons (HWE) reactions, in the synthesis of certain natural products. Relying on asymmetric HWE reactions to access key building blocks, two natu-ral products, pyranicin and pyragonicin, were synthesized from common late intermediates. The utility of the HWE reactions is highlighted through a desymmetrization of a meso-dialdehyde as well as a stereoconvergent reaction sequence employing the sequential use of a HWE parallel kinetic resolution fol-lowed by a Pd-catalyzed allylic substitution to convergently transform a race-mate to a single stereoisomer of the product. Methodological extensions of these syntheses include a divergent synthesis of 2,3,6-substituted tetrahydropyran derivatives and application of Zn-mediated asymmetric alkynylations to install key stereocenters. Synthetic studies directed towards a more complex target, mucocin, employing a triply convergent strategy, have also been performed. Expedient and reliable routes to three key fragments were developed, as well as methodology to access to all nine stereocenters. The fragment coupling to assemble the oligonuclear core still remains a challenge, however. Key features of the synthesis include the formation of two fragments from a common precursor derived from an asymmetric HWE desymmetrization, Zn-mediatedated asymmetric alkynylations, a stereoselective oxa-Michael cyclization dependent on a simultaneous protective group migration and a one-pot procedure for the synthesis of a TBS protected iodohydrin from a terminal epoxide. An investigation of the possibilities for developing a transition metal catalyzed asymmetric olefination using a chiral Re-complex is outlined. An enantioen-riched BINAP-Re complex was synthesized and characterized by X-ray. An efficient protocol for the olefination of functionalized aldehydes employing this catalyst was developed, but gave racemic products in two attempted kinetic resolutions of racemic substrates, most likely due to a reaction pathway proceeding via a non-metal associated phosphonium ylide. / QC 20100921

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