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Capture sélective du monoxyde de carbone par des corroles de cobalt et application à la mise au point d'un détecteur de gaz / Selective trapping of carbon monoxide with cobalt corroles to aim the development of a gas sensorQuesneau, Valentin 20 December 2018 (has links)
Ces travaux de thèse ont pour objectif la synthèse de nouveaux corroles de cobalt pour la détection à des concentrations sub-ppm de CO. La détection du monoxyde de carbone à de telles concentrations représente des enjeux de santé publique et industriel.Lors de ces travaux de thèse, les corroles de cobalt tétra-coordinés synthétisés se sont révélés instables dans le temps. Une nouvelle stratégie a été utilisée en se servant de ligands axiaux labiles comme groupements protecteurs des corroles de cobalt. Cette stratégie a permis d’élaborer un capteur détectant le monoxyde de carbone à des seuils de l’ordre du ppb.Enfin la dernière partie de ce travail concerne le développement de nouveaux matériaux poreux à base de corroles de cobalt dont les résultats se révèlent prometteurs pour la détection et le stockage du monoxyde de carbone. / This work aims to develop cobalt corroles for sub-ppm carbon monoxide detection. Surnamed “the silent killer”, detection at low-level of this gas represents a public health and an industrial challenge.During this work, synthesized tetra-coordinated cobalt corroles were found to be not stable over time. A new approach was developed, using labile axial ligands as protective groups of the tetra-coordinated cobalt corrole. This strategy leads to a ppb level detection sensor.The synthesis of new porous organic polymer based on cobalt corroles represents the last part of this work. Gas sorption measurement of these new materials are encouraging for their development for carbon monoxide detection or storage.
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Corrole Synthesis and Catalytic Applications Toward Cobalt(III)-Catalyzed Epoxidation, N-H Insertion, and CyclopropanationKim, Chung Sik 31 December 2010 (has links)
A variety of bromocorroles, useful precusors for Pd-based cross coupling, were sucessfully synthesized in moderate to good yields. Chiral corroles were also synthesized through use of chiral amides in the aforementioned cross coupling reactions. Cobalt complexes bearing π-acceptor (CNtBu) and σ-donor (PPh3) ligands were also prepared in excellent yields. In this dissertation, cobalt (III) corrole complexes were applied to three different reaction areas: epoxidation, N-H insertion, and cyclopropanation. Cobalt(III) corroles were found to be efficient catalysts for epoxidation reactions. The epoxidation reactions can be carried out using ethyl phenyldiazoacetate, an acceptor/donor diazo compound, as a carbenoid precusor.The reaction provided highly diastereoselective epoxides. In addition to epoxidation, N-H insertion reactions using cobalt(III) corroles as catalysts smoothly produced the desired products with diverse diazo reagents. The reactions were screened using ethyl phenyldiazoacetate with a selection of anilines and amides. In order to investigate non-ylide intermediate based metal-mediated catalytic reactions, cyclopropanation was conducted using cobalt (III) corroles as catalysts, producing the desired cyclopropyl nitroesters in high yields and with excellent diastereoselectivity under a concerted mechanism. Asymmetric cyclopropanation reactions were carried out using chiral cobalt(III) corrole complexes to generate the enatiomerically pure desired cyclopropanes in moderate yields.
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Aplicações da mobilidade iônica acoplada a espectrometria de massas como uma técnica analítica para o estudo de misturas complexas e separação de isômeros / Applications of ion mobility mass spectrometry as an analytical technique for the study of complex mixtures and isomers separationsLima, Maíra Fasciotti Pinto, 1987- 21 August 2018 (has links)
Orientador: Marcos Nogueira Eberlin / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-21T09:34:26Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012 / Resumo: Esta dissertação apresenta uma breve introdução sobre a técnica de mobilidade iônica acoplada a espectrometria de massas (Capítulo 1) e a discussão de resultados aplicados a três subprojetos distintos. A técnica de TWIM-MS é uma técnica de separação na qual a separação em dos íons ocorre em uma cela de mobilidade iônica e é baseada em parâmetros como a seção de choque, carga, polarizabilidade, que é a capacidade de um íon ter sua densidade eletrônica distorcida pela interação com o gás de mobilidade, além de, obviamente, da estrutura tridimensional dos íons em fase gasosa. Sobre o Capitulo 2, objetivo do trabalho em petroleômica foi desenvolver e otimizar um método para a identificação de compostos polares presentes em amostras de petróleo e seus derivados como diesel e gasolina, que fosse capaz de diferenciar amostras distintas com relação essas composições, verificando quais respostas esta técnica pode fornecer nos estudos petroleômicos. Puderam ser identificadas as classes N, O2 e NO, com excelente resolução com a técnica de TWIM-MS. Entretanto, acredita-se que algumas outras classes ainda podem ser elucidadas. O CO2 se mostrou ser o melhor gás de mobilidade a ser utilizado para a resolução destas classes. A técnica de TWIM-MS também se mostrou adequada para a caracterização de gasolina e seus aditivos, entretanto mais amostras de diesel aditivado devem ser investigadas, para se descobrir porque os aditivos não puderam ser detectados através da técnica de ESI-TWIM-MS. Com relação ao estudo das estruturas em fase gasosa dos isômeros do Corrol (Capítulo 3), podese observar que o corrorin tem a estrutura tridimensional mais compacta entre todos os isômeros, enquanto NCC4 e corrol são os isômeros com maiores seções de choque e maiores drift times. Mesmo que o norrole tenha os maiores valores previstos de CCS, seu menor momento de dipolo resulta em interações mais fracas com o gás de mobilidade, e um drift time menor do que o esperado é obtido. Uma melhor resolução entre os isômeros de corrol foi alcançada usando CO2 como gás de mobilidade. Além disso, estes isômeros podem ser diferenciados monitorando íons característicos resultantes de suas fragmentações. Em conclusão, mostrou-se que a diferenciação por TWIM-MS destas estruturas pode ser conseguida através do monitoramento das diferenças entre as suas mobilidades relativas e também pelos espectros distintos de MS/MS obtidos para cada isômero. Já o Capítulo 4, visou avaliar a separação de 4 dissacarídeos isoméricos, em que se observou que a utilização de mais gases polarizáveis, tais como o CO2 na análise realizada com o Synapt G2 permite uma resolução quase na linha de base, o que não foi possível utilizando N2 como gás de mobilidade e nem na primeira geração do equipamento comercial Synapt, mesmo usando CO2 como gás de mobilidade / Abstract: This dissertation presents a brief introduction of the technique of Ion Mobility Mass Spectrometry (Chapter 1) and also the discussion of results applied to three distinct subprojects. The technique of Traveling Wave Ion Mobility Mass Spectrometry, is a separation technique in which the separation of the ions occurs in a mobility cell and is based on parameters such as collision cross-section, charge, polarizability (the capacity of an ion to have its electronic density distorted by interaction with the drift gas) and the three dimensional structure (shape) of ions in the gaseous phase. The main goal of the work performed in petroleomics (Chapter 2), was to develop and optimize a method for the identification of polar compounds present in oil samples and its derivatives, such as diesel and gasoline. The applied method was able to differentiate oil samples based on some polar components. Classes N, O2 and NO could be identified with proper resolution with TWIM-MS technique. However, it is believed that some other classes may be elucidated. CO2 was shown to be the best drift gas to be used for the separation of these classes. The technique of TWIM-MS also proved to be suitable for the characterization of gasoline and its additives, however, more samples of additive diesel must be investigated to find out why the additives could not be detected by the technique of ESI-TWIM-MS. During the study of tridimensional structures in the gaseous phase of five Corrole isomers (Chapter 3), it was observed that significant differences in shape and charge distributions for the protonated molecules lead to contrasting gas phase mobilities, most particularly for corroin, the most "confused¿ isomer. Accordingly, corroin was predicted by DFT and collisional cross section calculations to display the most compact tridimensional structure. NCC4 and corrole, on the other hand were found to be the most planar isomers. Better resolution between the corrole isomers was achieved using the more polarizable and massive CO2 as the drift gas and contrasting labilities towards CID, allowed the prompt differentiation of some isomers. Chapter 4 aimed to evaluate the separation of four isomeric disaccharides, where it was observed that the use of more polarizable gases, such as CO2, in the analysis performed with a Synapt G2 allows almost a baseline resolution for some isomeric pairs. This was not possible using N2 as drift gas with the Synapt G2, and not with the Synapt G1 using either N2 or CO2 / Mestrado / Quimica Analitica / Mestra em Química
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