En la tesis doctoral se describe el desarrollo y empleo de metodologías para la síntesis de diferentes compuestos nitrogenados. En el primer capítulo se llevaron a cabo reacciones catalizadas por acetato de cobre(II). Se estudió la alquilación de aminas, carboxamidas, fosfinamidas y sulfonamidas a través de un proceso de autotransferencia de hidrógeno, empleando alcoholes como fuente del electrófilo. También se desarrollaron metodologías para la síntesis de aminas secundarias, mediante la reacción aza-Wittig indirecta, y para la síntesis de amidas primarias, a través de un reordenamiento de tipo Beckmann a partir de aldehídos. En el segundo capítulo se estudiaron reacciones catalizadas por acetato de paladio(II). Se diseñó un protocolo de alquilación de aminas, tanto por un proceso de autotransferencia de hidrógeno como a través de la reacción aza-Wittig indirecta, y se comprobó la selectividad de este protocolo para la alquilación de carboxamidas y, especialmente, sulfonamidas.

This thesis presents the synthesis of porphyrin arrays for light-harvesting applications using Wittig chemistry, which allows the construction of covalently bound systems that are conjugated, stable and easy to characterize. This was achieved using a dendrimer strategy utilizing tetraarylporphyrins as building blocks, monofunctionalized with either aldehyde or phosphonium salt groups at the β-pyrrolic position, and benzenes, polyfunctionalized with either aldehyde or phosphonium salt groups; stepwise control of the addition of each porphyrin moiety was thus obtained. In this way, different porphyrins in different metallated states were arranged in a determinate geometrical relationship, which is of great importance in the investigations on electron/energy transfers. Arrays containing up to five metalloporphyrin units (two kinds of porphyrins coordinating two different metals) were synthesized and characterized. The unexpected chromatography behaviour and 1H-NMR spectra of a Zn porphyrin functionalized with a 1,3-bis(methyl(diethylphosphonate) benzene were the reason for an investigation, which uncovered, mainly with the use of NMR spectrometry, the first case of intramolecular coordination between the Zn centre and a phosphonate group of the same porphyrin. The dynamic nature of this coordination was characterized and chemical-physical parameters for Zn porphyrin/phosphonate binding were determined. In order to establish the photophysical properties of our conjugated arrays, we synthesized a series of dyads containing Zn and free-base tetraphenylporphyrins (TPPs) connected through variable length phenylenevinylene-type bridges; along with this series, the preparation of the Zn and free-base homometallic homologue dyads and two series of monomers carrying the conjugated linker were realized. Collaboration with IFOS-CNR in Bologna, Italy was established in order to investigate the intramolecular photophysics of those systems, which involve efficient intramolecular energy transfer from the Zn to the free-base porphyrin. Finally, dyads composed of Fe(III) and Zn porphyrin were prepared as part of a project in collaboration with the University of Pennsylvania for the investigation of new artificial photosynthetic systems. Two series of dimers were prepared in order to obtain incorporation in both the classes of hydrophobic and hydrophilic proteins. TPPs were used for the making of the hydrophobic dyads while hydrophilicity was achieved by employing tetraester porphyrin derivatives, which can be quantitatively hydrolyzed to afford the correspondent water soluble acids. A new monosubstituted porphyrin was also synthesized and incorporated in the arrays to minimize steric hindrance inside the protein binding sites.

Thèses (M.A.)--Université de Sherbrooke (Canada), 2002. / Titre de l'écran-titre (visionné le 20 juin 2006). Publié aussi en version papier.

Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 206-216). Also available in electronic version. Access restricted to campus users.

Les deux objectifs principaux de cette thèse sont : la préparation de nouvelles cétones insaturées et l'étude de leurs propriétés dans les domaines biologiques et de la chimie des matériaux. La synthèse de nouveaux bis-ylures mixtes-(P,S) et l'étude de leur réactivité. Dans le premier chapitre, après une introduction bibliographique sur l'importance des cétones a,b-insaturées dans le domaine biologique, sont décrites les synthèses de nouvelles dichalcones et d'hydroxybenzylidène-indanones. Le deuxième chapitre est consacré à l'étude de la chimie de coordination des nouveaux composés préparés, avec un intérêt particulier pour les complexes de fer(0) pour les bis-chalcones et de fer(III) pour les hydroxybenzylidène-indanones. Quelques complexes de cuivre(II) et de vanadium(V) sont également décrits. Le troisième chapitre est dédié à l'utilisation des composés organiques et complexes organométalliques dans le domaine de la biologie, et plus particulièrement leur activité cytotoxique. Des résultats très encourageants ont été obtenus notamment comme anti-cancéreux potentiel contre les lignées cellulaires U-251 (glioblastome). Les complexes d'hydroxybenzylidène-indanones de fer(III) ont également été utilisés pour préparer des films minces présentant des propriétés intéressantes en tant que semi-conducteurs. La dernière partie de ce manuscrit de thèse contient un rappel sur la chimie des bis-ylures et leur potentiel en tant que source de carbone atomique. Il décrit ensuite la synthèse, la caractérisation et la réactivité de deux nouveaux modèles de bis-ylures mixtes-(P,S). / The present work concerns two main topics: the development of new unsaturated ketones and the study of their properties towards biological and material applications. The preparation of new (P,S)-bis-ylides, species that can behave as atomic carbon source. In the first chapter, a brief bibliographic overview describes the importance of unsaturated ketones for biological applications followed by the synthesis and characterization of new bis-chalcones and hydroxybenzylidene-indanones. The second chapter deals with the preparation of new organometallic complexes, more specifically new bis-chalcones iron(0) complexes and new hydroxybenzylidene-indanone iron(III) complexes. Most of these species have been characterized by X-Ray diffraction analysis. Some copper(II) and vanadium(V) are also described. The third chapter is dedicated to the study of the new organic and organometallic compounds towards applications in biology and materials science. Of special interest, hydroxybenzylidene-indanone iron(III) complexes exhibits excellent results as cytotoxic agents for U-251 cancer cells (glioblastome). In addition, some of the complexes synthesized are useful to prepare thins film displaying semi-conductor properties. The last chapter of this manuscript contains an overview on bis-ylide chemistry, more specifically towards the species that can behave as sources of elementary carbon. Then the synthesis, characterization and reactivity of two new (P,S)-bis-ylides are described.

Rosemarie Trockel: The Problem of Becoming is a theoretical investigation of the artwork of contemporary German artist Rosemarie Trockel (b. 1952). Although Trockel is best known for her knit canvas works made throughout the 1980s, she has a remarkably large oeuvre which utilizes almost every artistic medium possible – from video and film work, to public monuments, painting, earthworks, sculpture, drawing, installation art, book-making, photography, and even robotics. Trockel’s artwork is constantly changing stylistically and thematically, which makes her work difficult to write about but is also what makes her work unique. By opening up a multiplicity of readings that refuse a fixed symbolic order, her art represents a continuous state of becoming other. Ultimately this project claims that Rosemarie Trockel’s artwork exemplifies a ‘virgulian’ subjectivity and an aesthetics of becoming. This project reads Trockel’s art through the philosophers Gilles Deleuze and Felix Guattari, as well important feminist and queer theorists such as Griselda Pollock, Teresa de Lauretis, Marguerite Duras, Simone de Beauvoir, and Monique Wittig. It also uses the theoretical construct of the virgule as an alternative to common art historical methods such as gender, culture, biography, historicity, or intentionality. The virgule is a theoretical construct (representing both an aesthetic mode or style and a form of subjectivity), which is, ultimately, a new way of reading works of art and literature. Each chapter of this thesis demonstrates different ways in which the virgule operates within Rosemarie Trockel’s artwork. Chapter one, ‘BB/BB’, centres on Trockel’s vitrine work ‘The Bardot Box’ (1993), in which Trockel combines Brigitte Bardot and Bertolt Brecht. These two figures are used to explore concepts of myth, fandom, the rhizome, and adolescence. Chapter two, ‘Mermaid/Angel’, looks at Trockel’s sculpture Pennsylvania Station (1987), which is usually read as relating to the Holocaust. Here, instead, the work will be looked at in relation to fairy tales and mythological creatures. It will also demonstrate Trockel’s fascination with the history of art and how women’s bodies are constructed throughout that history. Chapter three, ‘Domestic/Violence’, discusses how Trockel’s work can relate to historical German events (namely, the activities of terrorist Group the Red Army Faction). It also demonstrates her interest in uncovering forgotten histories and people. Chapter four, ‘Body/Machine’, explains how Trockel’s sculptural machine Painting Machine and 56 Brushstrokes bridges the divide between mechanical production and the handmade. This chapter also discusses the very different ways in which Trockel’s work portrays bodies (visceral versus clinical). The concluding chapter of Rosemarie Trockel: The Problem of Becoming, ‘Across the/Continental Divide’ places Trockel’s video work ‘Continental Divide’ (1994) in dialogue with Monique Wittig’s novel Across the Acheron, to show how the virgule operates as a subject position, and to demonstrate the limits of a virgulian subjectivity.

Thesis advisor: James P. Morken / This dissertation details three main projects that focus on stereoselective synthesis of organoboron reagents and their application to total synthesis studies. The first chapter describes the development of an enantioselective palladium-catalyzed conjuntive cross-coupling of bis(alkenyl)borates to access chiral allylboron reagents. These reagents are of high synthetic value that is demonstrated through various applications. The second chapter describes the development of a diastereoselective amine-modified boron-Wittig reaction with ketone electrophiles to access trisubstituted alkenyl boronic esters. The synthetic utility of these trisubstituted alkenyl boronic esters is demonstrated through a novel palladium-catalyzed cross-coupling reaction. The third chapter encompassess studies toward the total synthesis of natural products amphidinolides C and F. It highlights the application of methods developed in the Morken laboratory in the context of challenging total synthesis. It also highlights the potential for newly developed conjunctive cross-coupling and boron-Wittig reactions to solve problems in total synthesis. / Thesis (PhD) — Boston College, 2020. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

This dissertation explores the history of social-constructionist theories of sexual difference through the surprising connection between Jean-Jacques Rousseau and the lesbian-feminist writer and theorist Monique Wittig. Wittig developed a social contract theory that radically denaturalized sexual difference, an approach she credited to Rousseau. I offer an interpretation of her appropriation of Rousseau that frames it within the French women’s liberation movement. Then, re-reading him through her lens, I argue that Rousseau too viewed sexual difference as a social construction. Chapter 1 argues that Wittig’s concept of “the lesbian” is modeled after Rousseau’s “natural man.” Wittig used this notion in the “lesbian question” quarrel in the women’s movement to depict human freedom after the abolition of sexual difference. In chapter 2, I show how Wittig interprets the social contract as a political and epistemological concept that encodes the presuppositions, like heterosexuality or race, which shape the social order and knowledge production. Through this concept, she engages in a debate with the anthropologist Claude Lévi-Strauss over Rousseau’s legacy. Chapter 3 demonstrates that Rousseau retooled the naturalist Georges-Louis Leclerc de Buffon’s methodology and data in order to denaturalize sexual difference. From there, he posited that sex originates in the transition from proper nouns to common nouns, and is therefore a linguistic construction. This construction allows humans to understand virtue, because without it, humans are unable to access their moral sense. In chapter 4, I argue that his novel Julie represents his most sustained effort to harness material science to favor the development of moral sense. The novel synthesizes spiritual exercises’ emphasis on linguistic representations with materialist ideas about language’s influence on the body. It calls on readers to use spiritual exercises to shape their sexual identities in order to conform with rigidly defined gender roles. In the conclusion, I bring Wittig and Rousseau together within a loosely existentialist framework. I argue that by severing the chain of necessity between biology and sex, they posit a meaninglessness underlying our sexual identities; they react differently to this abyss, but it is in their realization of it that their work has a striking relevance today.

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Chapter One presents an overview of phosphorus reagents for the carbon homologations of aldehydes and ketones leading to functionalized carbonyl derivatives. Select examples are provided to exemplify the utility of carbon homologation methodology in synthesis and asymmetric organocatalysis and in the total synthesis of natural products. The directing effect of acetals on regioselective ylide formation is explored in Chapter Two. Evidence is presented for ylide formation through a complex induced proximity effect with lithium bases under coordinating conditions. Moreover, four-carbon donors represent a limit for useful directed ylide formation with trialkylphosphine-derived Wittig salts in carbonyl homologation reactions. A facile approach to the synthesis of methyl vinyl ketones (MVKs), using acetonyl tripropylphosphoranes under mild conditions, is reported in Chapter Three. A library of diversely functionalized MVKs was synthesized as a demonstration of the scope and generality of the methodology. The application of MVKs as substrates for organocatalysis and as building blocks for useful polyketide intermediates is briefly highlighted. In Chapter Four, the two-carbon homologation methodology that was presented in the previous chapter is applied to the synthesis of the polyketide olivetol and a series of O-methyl derivatives. Cyclic diketone intermediates were aromatized with catalytic iodine and DMSO as a terminal oxidant. Modification of the solvent system allowed for the selective synthesis of mono- or dimethyl ethers of methyl olivetolate. The selectivity of this aromatization is further explored in the final chapter with more complex substrates. Chapter Five focuses on the synthesis of the meroterpene phytocannabinoids found in Cannabis sativa. A synthetic strategy involving the sequential condensation/[3+3]-annulation of citral with cyclic 1,3-diketones synthesized in the previous chapter. This afforded non-aromatic meroterpenes that were subjected to acid-mediated thermal rearrangement and catalytic oxidative aromatization. Evidence for chemoselectivity of the aromatization methodology was demonstrated and a synthesis of methyl cannabinolate is presented. / Thesis / Doctor of Philosophy (PhD) / Methodologies for the extension of aldehydes to functionalized olefins and their application to the synthesis of cannabinolic acid methyl ester are presented.