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181	Reactivity of well-defined organometallic copper(III) complexes in carbon-heteroatom bond forming reactions Casitas Montero, Alícia 01 June 2012 (has links) This thesis is focused on the unexplored field of organometallic copper(III) chemistry. Arylcopper(III) complexes have been proposed as key intermediates in Ullmann condensation reactions that consist in the coupling of aryl halides and heteroatom nucleophiles catalyzed by copper. The study of the reactivity of well-defined arylcopper(III) complexes may provide a better understanding of the mechanism of Ullmann condensation reactions, which is still under intense debate. In this doctoral dissertation we study the feasibility of well-defined arylcopper(III) complexes, which are stabilized within macrocyclic ligands, to participate in C-heteroatom bond forming reactions. We develop copper-catalyzed C-N and C-O bond forming reactions, as well halide exchange reactions, including fluorinations, based on Cu(I)/Cu(III) catalytic cycle within model aryl halide substrates. We uncover the fundamental understanding of the two-electron redox steps, oxidative addition and reductive elimination, at copper. / Aquesta tesi es centra en el camp de la química organometàl•lica del coure(III) que roman sense explorar. Els complexos arilcoure(III) s'han proposat com a intermedis clau en les reaccions de condensació Ullmann que consisteixen en l'acoblament d'halurs d'arils i nucleòfils basats en heteroàtoms catalitzades amb coure. L'estudi de la reactivitat de complexos arilcoure(III) ben definits pot proporcionar una millor comprensió del mecanisme de les reaccions de condensació Ullmann, el qual es troba sota un intens debat. En aquesta tesi doctoral s'estudia la viabilitat del complexos arilcoure(III), estabilitzats en lligands macrocíclics, de participar en reaccions de formació d'enllaç carboni-heteroàtom. S'han desenvolupat reaccions de formació d'enllaç C-N i C-O així com reaccions d'intercanvi d'halurs, on s'inclouen fluoracions, catalitzades amb coure i basades en un cicle catalític Cu(I)/Cu(III) utilitzant substrats models d'halur d'aril. S'ha obtingut una comprensió fonamental de les etapes redox a dos electrons, addició oxidant i eliminació reductiva, en coure. Reductive elimination Eliminació reductiva Eliminación reductiva Organometallic copper(III) Coure(III) organometàl·lic Cobre(III) organometálico Carbon-heteroatom bond Enllaç carboni-heteroàtom Enlace carbono-heteroátomo Copper catalysis Catàlisi amb coure Catálisis con cobre Fluorination Fluoració Fluoración Oxidative addition Addició oxidant Adición oxidante 547
182	Progrès vers la synthèse totale de la calyciphylline B Ly, Vu Linh 12 1900 (has links) Les alcaloïdes Daphniphyllum constituent une vaste famille de produits naturels isolés à partir de plantes à feuillage persistant couramment utilisés dans la médecine chinoise traditionnelle. Ils affichent une gamme impressionnante d'activités biologiques; antipyrétique, anti-inflammatoire, antioxydant et même anticancéreux. La calyciphylline B appartient à cette famille et possède un motif original comprenant sept stéréocentres adjacents, dont un stéréocentre quaternaire tout carbone, avec un échafaudage hexacyclique. Sa structure a été déterminée par données spectroscopiques, plus précisément par des techniques de RMN 2D. Malgré le peu d'information sur son activité biologique, sa synthèse représente sans le moindre doute un grand défi pour les chimistes organiciens. Le groupe de recherche du Prof. Hanessian a entrepris la synthèse totale de la calyciphylline B en 2010, laquelle est toujours en cours. Une nouvelle approche a été développée pour la préparation d'un intermédiaire azabicyclo[3.3.0]octane avancé. Ce mémoire résume les travaux de recherche de l'auteur sur les progrès réalisés pour la voie alternative élaborée par le groupe du prof. Hanessian. Le travail effectué comprend la formation d'un stéréocentre quaternaire, l'alkylation d'un énolate sur un triflate d'alkyle secondaire, une réduction diastéréosélective, une cyclisation réductrice ainsi qu'une oxydation de Wacker régiosélective. / The Daphniphyllum alkaloids constitute a broad class of natural products isolated from a genus of evergreen plants extensively used in traditional Chinese medicine. These alkaloids display an impressive range of biological activities, including antipyretic, anti-inflammatory, antioxidant, and even anticancer properties. Calyciphylline B is a structurally unique member of this family containing seven contiguous stereocenters including an all-carbon quaternary stereocenter with a fused-hexacyclic ring scaffold. Its structure was determined by spectroscopic methods, especially 2D NMR techniques. Despite the sparse availability of information on its biological activity, its synthesis is undoubtedly a great challenge for synthetic chemists. The research group of Prof. Hanessian embarked on the total synthesis of calyciphylline B in 2010 and the project is still ongoing. A new route was developed for the preparation of an advanced azabicyclo[3.3.0]octane intermediate. This thesis summarizes the research work of the author on the progress made for the synthetic route developed by the Hanessian group. The work done includes the formation of a quaternary stereocenter, alkylation of an enolate using a secondary alkyl triflate, diastereoselective reduction, reductive cyclization, and a regioselective Wacker oxidation. Calyciphylline B synthèse totale approche chiron stéréocentre quaternaire alkylation d'énolate amination réductrice déplacement SN2 inversion de configuration pyrrolidine bicyclique Calyciphylline B total synthesis chiron approach quaternary stereocenter enolate alkylation reductive amination SN2 displacement inversion of configuration bicyclic pyrrolidine
183	Study of compact quantum groups with probabilistic methods : caracterization of ergodic actions and quantum analogue of Noether's isomorphisms theorems / Etude des groupes quantiques compacts avec des méthodes probabilistes : caractérisation d'actions d'action ergodiques et analogues quantiques des théorèmes d'isomorphismes de Noether Omar hoch, Souleiman 29 June 2017 (has links) Cette thèse étudie des problèmes liés aux treillis des sous-groupes quantiques et la caractérisationdes actions ergodiques et des états idempotents d’un groupe quantique compact.Elle consiste en 3 parties. La première partie présente des résultats préliminaires sur lesgroupes quantiques localement compacts, les sous-groupes quantiques normaux ainsi queles actions ergodiques et les états idempotents. La seconde partie étudie l’analogue quantiquede la règle de modularité de Dedekind et de l’analogue quantique des théorèmesd’isomorphisme de Noether ainsi que leur conséquences comme le théorème de raffinementde Schreier, et le théorème Jordan-Hölder. Cette partie s’inspire du travail de recherche deShuzhouWang sur l’analogue quantique du troisième théorème d’isomorphisme de Noetherpour les groupes quantiques compacts ainsi que le travail récent de Kasprzak, Khosraviet Soltan sur l’analogue quantique du premier théorème d’isomorphisme de Noether pourles groupes quantiques localement compacts. Dans la troisième partie, nous caractérisonsles états idempotents du groupe quantique compact O−1(2) en s’appuyant sur la caractérisationde ses actions ergodiques plongeables. Cette troisième partie est dans la lignedes travaux fait par Franz, Skalski et Tomatsu pour les groupes quantiques compactsUq(2), SUq(2) et SOq(3). Nous classifions au préalable les actions ergodiques et les actionsergodiques plongeables du groupe quantique compact O−1(2).Les travaux présentés dans cette thèse se basent sur deux articles de l’auteur et al.Le premier s’intitule “Fundamental isomorphism theorems for quantum groups” et a étéaccepté pour publication dans Expositionae Mathematicae et le second est intitulé “Ergodicactions and idempotent states of O−1(2)” et est en cours de finalisation pour être soumis. / This thesis studies problems linked to the lattice of quantum subgroups and characterizationof ergodic actions and idempotent states of a compact quantum group. It consistsof three parts. The first part present some preliminary results about locally compactquantum groups, normal quantum subgroups, ergodic actions and idempotent states. Thesecond part studies the quantum analog of Dedekind’s modularity law, Noether’s isomorphismtheorem and their consequences as the Schreier refinement theorem and theJordan-Hölder theorem. This part completes the work of Shuzhou WANG on the quantumanalog of the third isomorphism theorem for compact quantum group and the recentwork of Kasprzak, Khosravi and Soltan on the quantum analog of the first Noether isomorphismtheorem for locally compact quantum groups. In the third part, we characterizeidempotent states of the compact quantum group O−1(2) relying on the characterizationof embeddable ergodic actions. This third part is in the sequence of the seminal works ofFranz, Skalski and Tomatsu for the compact quantum groups Uq(2), SUq(2) and SOq(3).We classify in advance the ergodic actions and embeddable ergodic actions of the compactquantum group O−1(2).This thesis is based on two papers of the author and al. The first one is entitled“Fundamental isomorphism theorems for quantum groups” which have been accepted forpublication in Expositionae Mathematicae and the second one is entitled “Ergodic actionsand idempotent states of O−1(2)” and is being finalized for submission. Groupe quantique localement commpact Groupe quantique discret Groupe quantique linéairement réductif Lemme de Zassenhaus Théorème de raffinement de Schreier Action ergodique Théorème d'isomorphismes de Noether Groupe quantique compact État idempotent Règle de modularité de Dedekind Compact quantum group Idempotent state Normal quantum subgroup Ergodic action Noether's isomorphisme theorem Discrete quantum group Linearly reductive quantum group Zassenhaus lemma Schreier refinement theorem Jordan-Hölder theorem Dedekind’s modularity law 515
184	Influência dos nutrientes nitrogênio e fósforo na degradação anaeróbia do pentaclorofenol e na diversidade microbiana dos sedimentos enriquecidos do Estuário de Santos-São Vicente, Estado de São Paulo / Influence of nitrogen and phosphorus nutrients on the anaerobic degradation of pentachlorophenol and on the natural microbial diversity of sediments from the Santos-São Vicente estuary, state of São Paulo, Brazil Gunther Brucha 01 October 2007 (has links) A pesquisa que ora se apresenta visou estabelecer as condições nutricionais adequadas para o uso do sedimento do estuário de Santos - São Vicente do Estado de São Paulo, como inóculo no reator anaeróbio horizontal de leito fixo (RAHLF) no processo de degradação anaeróbia do pentaclorofenol (PCP) em busca da aplicação da tecnologia em escala real, assim como identificar grupos microbianos envolvidos no processo. Para tanto, sedimento do estuário de Santos-São Vicente, com características metanogênicas foi utilizado. Os microrganismos provenientes do sedimento estuarino foram enriquecidos sob condições metanogênicas e halofílicas, visando a utilização do sedimento como inoculo nos ensaios nutricionais e na operação dos reatores do tipo RAHLF. O meio de cultivo salino Biota, suplementado com glicose e formiato, foi utilizado para o desenvolvimento da comunidade microbiana metanogênica halofílica. Testes de degradação do PCP foram realizados previamente sob diferentes concentrações de nitrogênio e fósforo, com vistas a uma melhor compreensão da relação N:P adequada para o processo anaeróbio. Os resultados provenientes do acompanhamento da diversidade microbiana do domínio Bacteria nas diferentes relações testadas indicaram a seleção de distintas comunidades microbianas, resultando em diferentes velocidades de degradação do PCP. A relação N:P de 10:1 foi a que apresentou melhores resultados, pois além da rápida degradação do PCP quando comparada com as outras relações, apresentou a maior diversidade de microrganismos. Posteriormente, o sistema RAHLF foi operado com vazão média afluente de aproximadamente 44 mL/hora, com meio mineral salino Biota (DQO:N:P de 1000:130:45) para R1 e com a alteração para relação DQO:N:P de 1000:10:1 para R2. Duas diferentes estratégias foram adotadas para partida dos reatores. Para R1, optou-se por acrescentar PCP na concentração inicial de 10,0 mg/L, durante 110 dias causando desestabilização da metanogênese e acúmulo de PCP, requerendo intervenção para recuperação do reator pelo período de 90 dias. Na partida do RAHLF 2, optou-se pelo aumento gradual de concentração do PCP de 0,5 mg/L a 12,0 mg/L durante 52 dias. Após estabelecimento da metanogêsenese, R1 foi alimentado durante 270 dias com 5,0 mg PCP/L, durante 41 dias com 8,0 mg/L e 59 dias com 12 mg/L. O balanço de massa no reator RAHLF 1 demonstrou que 0,52% do PCP adicionado saiu no efluente e que não ocorreu adsorção no sistema. 22,34 mg de 2,4,6 TCP, intermediário da degradação do PCP, ficaram adsorvidos na biopartícula. Os resultados das análises de diversidade microbiana apontaram para mudança da comunidade microbiana do domínio Bacteria ao longo do período operacional e morfologias de bacilos fluorescentes semelhantes a Methanobacterium sp estiveram presentes no reator. No RAHLF 2, a degradação do PCP foi de 100%, até a concentração de 10,0 mg/L. No final da fase com 12,0 mg PCP/L, a concentração no efluente foi de 1,4 mg PCP/L, com eficiência média de remoção de 93,2 \'+ ou -\' 5,5%. 2,4,6 TCP foi o intermediário principal no efluente do reator. 4,06% do PCP adicionado ao sistema foram encontradas no efluente e 15,94% ficaram adsorvidas nas biopartículas do reator. Portanto, considera-se que 80% do PCP adicionado sofreu degradação anaeróbia microbiana. A presença dos microrganismos Methanocalcullus e Methanosaeta na fase final de operação do RAHLF 2 e determinadas no sedimento coletado foi considerada fundamental para manter estabilidade do reator. Essa descoberta contribui com informações sobre a real diversidade microbiana de ecossistemas tropicais, sobretudo em habitats anaeróbios, bem como sobre as condições nutricionais e os procedimentos necessários para confiná-la em reatores e usá-la em processos de biorremediação. / The research presented here aimed to determine the optimal nutritional conditions for the use of sediment from the Santos-São Vicente estuary in the state of São Paulo, Brazil, as an inoculum for a horizontal-flow anaerobic immobilized biomass reactor (HAIB) applied to the anaerobic degradation of pentachlorophenol (PCP), seeking to apply the technology on the real scale and to identify the microbial groups involved in the process. To this end, sediment with methanogenic characteristics from the Santos-São Vicente estuary was used. The microorganisms from the estuarine sediment were enriched under methanogenic and halophilic conditions, aiming to use the sediment as an inoculum in nutritional assays and in the operation of HAIB reactors. Biota saline culture medium supplemented with glucose and formiate was used to develop the halophilic methanogenic microbial community. PCP degradation tests were carried out previously under different concentrations of nitrogen and phosphorus in order to gain a better understanding of the optimal N:P ratio for the anaerobic process. The findings on the microbial diversity of the domain Bacteria at the various ratios tested here indicated the selection of distinct microbial communities, resulting in different PCP degradation velocities. The N:P ratio utilized was 10:1 since it presented the best results not only in terms of faster PCP degradation than the other ratios but also highest diversity of microorganisms. The HAIB reactor was then operated with a mean inflow of approximately 44 mL/hour, using the biota saline mineral medium with a COD:N:P ratio of 1000:130:45 in R1 (reactor 1) and a COD:N:P ratio of 1000:10:1 in R2. Two distinct strategies were adopted to start up the reactors. In R1 PCP was added at an initial concentration of 10.0 mg/L for 100 days, causing destabilization of the methanogenesis and accumulation of PCP, requiring a 90-day intervention for the reactor\'s recovery. To start up R2, the PCP concentration was increased gradually from 0.5 mg/L to 12.0 mg/L for 52 days. After methanogenesis was established, R1 was fed for 270 days with 5.0 mg of PCP/L, followed by 41 days with 8.0 mg/L and 59 days with 12 mg/L. The mass balance in R1 indicated that 0.52% of the added PCP exited through the reactor\'s outflow and that adsorption of the system did not occur. 22.34 mg of 2,4,6 TCP, an intermediary of PCP degradation, was adsorbed in the bioparticles. The results of the analysis of microbial diversity indicated a change in the microbial community of the domain Bacteria along the operational period, with fluorescent bacilli morphologies resembling Methanobacterium sp present in the reactor. PCP degradation in R2 was 100% up to a concentration of 10.0 mg/L. At the end of the phase with 12.0 mg PCP/L, the effluent concentration was 1.4 mg PCP/L, with a mean removal efficiency of 93.2 \'+ or -\' 5,5%. 2,4,6 TCP was the main intermediary in the reactor\'s effluent. 4.06% of the PCP added to the system was found in the effluent and 15.94% was absorbed in the bioparticles of the reactor. Therefore, it was concluded that 80% of the added PCP underwent microbial anaerobic degradation. The presence of Methanocalcullus and Methanosaeta microorganisms in the final operating phase of R2, which was determined in the collected sediment, was considered fundamental for maintaining the reactor\'s stability. This discovery contributes to the body of information about the real microbial diversity of tropical ecosystems, above all in anaerobic habitats, and about the nutritional conditions and procedures involved in confining these microorganisms in reactors and using them in bioremediation processes. Arquéias metanogênicas halofílicas Biorremediação anaeróbia Desalogenação redutiva do PCP Estuário de Santos-São-Vicente Teoria dos recursos limitantes Anaerobic bioremediation Halophilic methanogenic archaea Reductive dehalogenation of PCP Resource ratio theory Santos-São Vicente estuary
185	From Copper to Gold: Identification and Characterization of Coinage-Metal Ate Complexes by ESI Mass Spectrometry and Gas-Phase Fragmentation Experiments Weske, Sebastian 30 January 2019 (has links) No description available. 540 coinage metal copper silver gold cuprate argentate aurate ate complex organocuprate organoargentate organoaurate magnesium organocuprate normant cuprate Cu(I) Cu(III) Ag(I) Ag(III) trifluoromethylation copper-mediated trifluoromethylation ruppert prakash c-c coupling cross coupling silver-mediated cross-coupling reactive intermediate reductive elimination counter ion effect esi ms esi-ms gas-phase fragmentation collision-induced dissociation cid gas-phase experiment gas-phase chemistry ion chemistry curiosity driven research Chemie (PPN62138352X)
186	Real impossible worlds : the bounds of possibility Kiourti, Ira Georgia January 2010 (has links) Lewisian Genuine Realism (GR) about possible worlds is often deemed unable to accommodate impossible worlds and reap the benefits that these bestow to rival theories. This thesis explores two alternative extensions of GR into the terrain of impossible worlds. It is divided in six chapters. Chapter I outlines Lewis’ theory, the motivations for impossible worlds, and the central problem that such worlds present for GR: How can GR even understand the notion of an impossible world, given Lewis’ reductive theoretical framework? Since the desideratum is to incorporate impossible worlds into GR without compromising Lewis’ reductive analysis of modality, Chapter II defends that analysis against (old and new) objections. The rest of the thesis is devoted to incorporating impossible worlds into GR. Chapter III explores GR-friendly impossible worlds in the form of set-theoretic constructions out of genuine possibilia. Then, Chapters IV-VI venture into concrete impossible worlds. Chapter IV addresses Lewis’ objection against such worlds, to the effect that contradictions true at impossible worlds amount to true contradictions tout court. I argue that even if so, the relevant contradictions are only ever about the non-actual, and that Lewis’ argument relies on a premise that cannot be nonquestion- beggingly upheld in the face of genuine impossible worlds in any case. Chapter V proposes that Lewis’ reductive analysis can be preserved, even in the face of genuine impossibilia, if we differentiate the impossible from the possible by means of accessibility relations, understood non-modally in terms of similarity. Finally, Chapter VI counters objections to the effect that there are certain impossibilities, formulated in Lewis’ theoretical language, which genuine impossibilia should, but cannot, represent. I conclude that Genuine Realism is still very much in the running when the discussion turns to impossible worlds.
187	Action in Chronic Fatigue Syndrome: an Enactive Psycho-phenomenological and Semiotic Analysis of Thirty New Zealand Women's Experiences of Suffering and Recovery Hart, M J Alexandra January 2010 (has links) This research into Chronic Fatigue Syndrome (CFS) presents the results of 60 first-person psycho-phenomenological interviews with 30 New Zealand women. The participants were recruited from the Canterbury and Wellington regions, 10 had recovered. Taking a non-dual, non-reductive embodied approach, the phenomenological data was analysed semiotically, using a graph-theoretical cluster analysis to elucidate the large number of resulting categories, and interpreted through the enactive approach to cognitive science. The initial result of the analysis is a comprehensive exploration of the experience of CFS which develops subject-specific categories of experience and explores the relation of the illness to universal categories of experience, including self, ‘energy’, action, and being-able-to-do. Transformations of the self surrounding being-able-to-do and not-being-able-to-do were shown to elucidate the illness process. It is proposed that the concept ‘energy’ in the participants’ discourse is equivalent to the Mahayana Buddhist concept of ‘contact’. This characterises CFS as a breakdown of contact. Narrative content from the recovered interviewees reflects a reestablishment of contact. The hypothesis that CFS is a disorder of action is investigated in detail. A general model for the phenomenology and functional architecture of action is proposed. This model is a recursive loop involving felt meaning, contact, action, and perception and appears to be phenomenologically supported. It is proposed that the CFS illness process is a dynamical decompensation of the subject’s action loop caused by a breakdown in the process of contact. On this basis, a new interpretation of neurological findings in relation to CFS becomes possible. A neurological phenomenon that correlates with the illness and involves a brain region that has a similar structure to the action model’s recursive loop is identified in previous research results and compared with the action model and the results of this research. This correspondence may identify the brain regions involved in the illness process, which may provide an objective diagnostic test for the condition and approaches to treatment. The implications of this model for cognitive science and CFS should be investigated through neurophenomenological research since the model stands to shed considerable light on the nature of consciousness, contact and agency. Phenomenologically based treatments are proposed, along with suggestions for future research on CFS. The research may clarify the diagnostic criteria for CFS and guide management and treatment programmes, particularly multidimensional and interdisciplinary approaches. Category theory is proposed as a foundation for a mathematisation of phenomenology. action Chronic Fatigue Syndrome Myalgic Encephalomyelitis Chronic Immune Deficiency Syndrome enaction social enaction social enactivism enactive psycho-phenomenological psychophenomenological vipassana groundlessness mind-body korper leib co-generative Focusing co-creative environment Antonio Damasio reciprocal constraints Pierre Vermersch Claire Petitmengin Antione Lutz narrative discourse phenomenal invariants Evan Thompson Merleau-Ponty Algirdis Julien Greimas Husserl first-person Fransisco Varela modelling invariants Natalie Depraz isotope John Boyd OODA loop Jonathan Shear Shaun Gallagher Arthur Kleinman Humberto Maturana second-person Alva Noe Dan Zahavi stages Embodied Mind Canterbury Wellington New Zealand non-dual non-reductive embodied phenomenological third-person graph-theoretical cluster analysis cognitive science experience solution subject-specific categories universal categories universal categories self energy illness process intersubjectivity Mahayana Buddhism contact narrative recovered making sense recursive loop perception dynamical decompensation neurology diagnosis empathy treatment management neurophenomenological neurophenomenology consciousness veracity agency multidimensional interdisciplinary category theory enculturation mathematisation of phenomenology interview nomenclature diagnostic criteria incidence prevalence coping strategy etiology epidemiology psychosomatic medicine meaning women girl female anthropology sociology cognitive behavioral therapy exercise therapy recovery mindful awareness suffering symbolisation Prasangika no-self aggregates wheel of karma cognition basic element analysis mental factors operational closure stereotypes enactive ontologically fragile self grief process-knowledge epoche phenomenal invariants textual invariants compound meaning saturation formalisation cluster analysis inter-session review inter-individual validation explicitation interview intricacy confidence psychophenomenology self-esteem sanction self dis-integration permanence continuity ego-self emotion surrender semiotic square meditation empathy semiotic compassion existential feelings goal obstruction movement transformation change somatic Giovanna Colombetti agoraphobia panic anxiety psychotherapy sleep rest pain weakness strength stamina Diego Cosmelli heaviness food chemicals allergy recovering despair frustration helplessness fear efference valence afference as-if-body-loop consciousness representation attention recovery intention sustainable sustainability neurasthenia existential feelings asthenia hysteria mononucleosis samatha-vispasnya prajna vijnana Eugene Gendlin Abhidharma dukkha shamatha interdependence vipashyana

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