Ce travail théorique a été réalisé dans le cadre général du développement de nouveaux composants mémoires utilisant le stockage de charges grâce à des molécules rédox. Une collaboration combinant recherche fondamentale, dans notre laboratoire, et recherche appliquée avec des équipes du CEA/LETI a conduit à la conception de systèmes hybrides constitués d'une monocouche de molécules rédox greffées sur la surface de silicium, les différents états de charge des molécules servant à stocker l'information. Notre but était de comprendre les paramètres (molécule, lien) gouvernant les transferts de charge et les propriétés électriques de tels systèmes. L'objectif principal de la thèse a donc été de modéliser les propriétés électroniques de molécules rédox et des systèmes résultants de leur greffage sur Si, à l'aide de méthodes basées sur la Théorie de la Fonctionnelle de la Densité. Un premier volet a été consacré à l'étude de processus rédox dans des porphyrine métallées intéressantes pour leur bistabilité. Un deuxième volet rassemble toutes les études sur les systèmes de molécules rédox greffées sur Si. En raison de leur nature hybride, deux approches ont été utilisées. La première, basée sur une description moléculaire où la surface de Si est modélisée par un aggrégat, conduit à des données importantes telles que le gap HOMO-LUMO, la localisation des charges ou les propriétés structurales. La deuxième basée sur des calculs de système périodique où la surface de Si est infinie, donne accès aux densités d'états. Ces données ont été ensuite comparées aux calculs moléculaires et discutées en liaison avec les propriétés électriques déterminées sur des composants tests.

In dieser Arbeit wird die Entwicklung und Charakterisierung neuer „smarter“ Redoxhydrogele mit drei verschiedenen funktionellen Eigenschaften und deren erfolgreicher Einsatz zur elektrochemischen Kontaktierung von Oxidoreduktasen beschrieben. Diese neuen Redoxpolymere 1. tragen kovalent integrierte Redoxzentren umgeben von einer hydrophilen Polymermatrix, 2. reaktive Kopplungsgruppen für den Aufbau selbstassemblierter Polymerschichten auf Elektrodenoberflächen und 3. lassen sich in ihrer Redoxaktivität durch Verwendung „intelligenter“ Polymere über externe Stimuli kontrollieren. Die Redoxhydrogele wurden nach dem Vorbild eines Baukastensystems in einfachen Ein-Stufen-Synthesen synthetisiert. Dazu wurden verschiedene Redoxzentren (Ferrocen, 1,10-Phenanthrolin-5,6-dion und 4-Carboxy-2,5,7-Trinitro-9-fluorenon), reaktive Kopplungsgruppen (Epoxy-, Amino-, Thiol- oder Disulfidfunktionen) und Polymermatrices (Poly-(N-Isopropylacrylamid) (PNIPAM) und Poly(ethylenglykolmethacrylat) (PEGMA)) in unterschiedlichen Zusammensetzungen miteinander copolymerisiert. Die Polymere wurden in Form von dünnen Polymerfilmen über die wiederholenden Funktionalitäten auf Elektrodenoberflächen aufgebracht und physiko- und elektrochemisch charakterisiert. Durch die erstmals gezeigte, derartige Ankopplung der Polymere, entstehen dreidimensionale, hydrophile selbstassemblierte Polymerschichten. Die Elektronentransferwege sind kurz und der Elektronentransfer effizient. Diese Polymer-modifizierten Elektroden wurden für die Kontaktierung von zwei exemplarisch ausgewählten Oxidoreduktasen eingesetzt, die Nicotinsäureamid-adenin-dinucleotid-abhängige Glucosedehydrogenase (NAD-GDH), welche ein freibewegliches Coenzym und die Pyrrolochinolinchinon-abhängige Glucosedehydrogenase (PQQ-GDH), welche ein prosthetisches Coenzym verwenden. Die Redoxaktivitäten des PNIPAMFoxy- und PEGMA-Fc-Polymers ließen sich durch externe Stimuli in Form von Temperatur und Calciumkonzentrationen kontrollieren. Ein Modell für die Komplexierung der Calciumionen durch die PEG-Seitenketten unter Ausbildung Kronenether-ähnlicher Strukturen und der daraus resultierenden Steigerung des Elektronentransfers wurde gezeigt. / This work describes the development and characterization of new, smart redox polymeres with three functionalities and their use in electrochemical wiring of oxidoreductases. These polymers 1. bear redox-active sites surrounded by hydrophilic polymeric matrix 2. surface-reactive groups to create self-assembled monolayers on electrodes 3. ionic-tunable redox activities by using stimuli-responsive polymers The syntheses of the redoxpolymers were resolved in simple one-step approaches using a building block system. Different mediators (ferrocene, 1,10-phenanthroline-5,6-dione and 4-carboxy-2,5,7-trinitro-9-fluorenone), reactive anchoring groups (groups epoxide, amine, thiol and disulfide) and polymer matrices (poly-(N-isopropylacrylamide) (PNIPAM), poly(ethylene glycol methacrylate) (PEGMA)) were copolymerized in different compositions. The polymers were anchored to electrode surfaces via the repetitive functionalities and physico- and electrochemical characterized. This kind of anchoring of the redoxpolymers was shown for the first time and three-dimensional hydropilic self-assembled polymer monolayers are created. The electron transfer pathways are short and the electron tranfer efficient. The polymer-modified electrodes were applied for wiring two oxidoreductases, nicotinamide-adenine-dinucleotide-dependent glucose dehydrogenase (NAD-GDH) with a diffusing coenzyme and the pyrroloquinoline quinone-dependent glucose dehydrogenase (PQQ-GDH) with a prosthetic coenzyme. The redox activities of PNIPAMFoxy and PEGMA-Fc-SS are tuneable with external stimuli like temperature and calcium concentrations. A model for the complexation of calcium by PEG side chains and the explanation of the resulting effects was shown.

Pyrazoles have been studied for over a century as an important class of heterocyclic compounds and continue to attract considerable interest due to the broad range of biological activities they possess. The incorporation of the essential structural features of pyrazoles with a ferrocene moiety could provide new derivatives with unexpected and/or enhanced biological activities since several ferrocene derivatives have already been shown to be active against a number of tumors. For this reason, we investigated the synthesis of ferrocenyl-substituted pyrazoles, such as 1-alkyl/aryl-5-ferrocenylpyrazoles, by employing the reaction between (2-formyl-1-chlorovinyl)ferrocene and hydrazine derivatives. Although this reaction is known, it was not studied in much detail and the low yields of ferrocenyl pyrazoles were obtained. Thus, we have reinvestigated this reaction and improved the yields of pyrazoles by optimizing the reaction conditions. (2-Formyl-1-chloro vinyl)ferrocene was first reacted with the excess amount (3 equivalents) of hydrazine derivative at 25 0C in dioxane under argon for 2 hours, and the resulting mixture was then heated at 100 0C for 6 hours in the same solvent. Under our optimized conditions, these reactions afforded 1-alkyl/aryl-5-ferrocenylpyrazole derivatives in moderate to good yields as a single or major product of the reaction. In some cases, 1-alkyl/aryl-3-ferrocenylpyrazole derivatives resulted from these reactions as very minor products.

Dans cette thèse, l'étude de la dépostion des molécules de ferrocène sur un substrat de Cu(111) par des simulations de dynamique moléculaire par premiers principes, en particulier, la dynamique moléculaire utilisant l'approche de Born-Oppenheimer (BOMD: Born-Oppenheimer Molecular Dynamics) et celle utilisant la fonctionnelle de l'énergie libre (FEMD: Free Energy Molecular Dynamics), combinées avec les études expérimentales par microscopie à effet tunnel (STM) à basse température et à courant constant ont montré que ces molécules de ferrocène peuvent être physisorbées sur un substrat de cuivre sans donner lieu à une dissociation moléculaire. Ce qui constitue un système idéal pour étudier la dynamique des états d'interfaces et leur réactivité par rapport à la déposition d’atomes métalliques. En particulier, la déposition d'un atome de Cuivre au dessus d'une molécule de ferrocène équilibrée sur le substrat de cuivre, conduit à un transfert de charges de cet atomes vers le substrat de Cu(111). On montre aussi que ces états d'interfaces ont le comportement bidimensionnel d'un gas d'électrons libres. / First-principles simulations studies, in particular Born-Oppenheimer molecular dynamics (BOMD) and free energy molecular dynamics (FEMD), combined with low-temperature scanning tunneling microscopy (STM) and spectroscopy reveal a non dissociative physisorption of ferrocene molecules on a Cu(111) surface, giving rise to ordered molecular layers. At the interface, a 2D-like electronic band is found, which shows an identical dispersion as the Cu(111) Shockley surface-state band. Subsequent deposition of Cu atoms forms charged organometallic compounds that localize interface-state electrons.

Submitted by Franciele Moreira (francielemoreyra@gmail.com) on 2017-09-13T16:28:44Z No. of bitstreams: 2 Dissertação - Evellyn Gonçalves de Souza - 2017.pdf: 2198173 bytes, checksum: 0e490bd8b1f7554afb334a3e27faf8ef (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-09-19T13:57:54Z (GMT) No. of bitstreams: 2 Dissertação - Evellyn Gonçalves de Souza - 2017.pdf: 2198173 bytes, checksum: 0e490bd8b1f7554afb334a3e27faf8ef (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-09-19T13:57:54Z (GMT). No. of bitstreams: 2 Dissertação - Evellyn Gonçalves de Souza - 2017.pdf: 2198173 bytes, checksum: 0e490bd8b1f7554afb334a3e27faf8ef (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-08-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Dengue is an endemic disease that causes wide concern both the health systems and to the patients. Thus, it is important that studies aiming at diagnoses faster and with possibility of field application can be developed for the medical intervention happens early, avoiding the worsening of the cases. Therefore, the aim of this work was to develop an electrochemical biosensor based on the use of aptamer as a bioelement for recognition on the surface of the boron doped diamond electrode (BDD) for the detection of each of the four serotypes of the dengue virus. Previously to the development of the biosensor, the dot-blot and apta-PCR techniques were used as validation methods for the interaction between aptamer B07 and target, the 5'UTR region present in the viral genome. The cyclic voltammetry technique was used in the analysis of redox reactions on the surface of the BDD electrode with and without modification of its surface with chitosan film. Ferrocene was used as the redox mediator and electroactive indicator of hybridization of the DNA strands formed in the sensor. The peaks of current indicated that the electrode with chitosan film modification on its surface presented greater stability. The redox compound had higher affinity for the double chains hybridized on the surface of the electrode, showing current values for DENV 1, 2, 3 and 4 of were 0.73; 0.69; 0.79 and 1.03 μA, respectively. These values were higher than the current found for the single-stranded aptamer (ssDNA), which was 0.62 μA, as well as for the current obtained from the aptamer hybridized with its complementary strand (dsDNA) whose value was 0.91 μA. Analyzes with time variations were performed showing a reduction in current values as a function of time, probably due to the reduction of the interaction of the electroactive material in the sensor. The aptasensor developed here showed good detection distinction between nucleic acid sequences, presenting potential for application in the detection of dengue virus. / A dengue é uma doença endêmica que causa grande preocupação tanto aos sistemas de saúde quanto aos pacientes. Dessa forma, é importante que estudos visando diagnósticos mais rápidos e com possibilidade de aplicação a campo possam ser desenvolvidos para que a intervenção médica possa ser precoce, evitando-se o agravamento dos casos. Neste sentido, buscou-se no presente trabalho desenvolver um biossensor eletroquímico baseado no uso de aptâmero como bioelemento reconhecedor na superfície do eletrodo de diamante dopado com boro (DDB) para a detecção de cada um dos quatro sorotipos do vírus da dengue. Previamente ao desenvolvimento do biossensor, as técnicas de dot-blot e apta-PCR foram utilizadas como métodos de validação da interação entre o aptâmero B07 e alvo, a região 5’UTR presente no genoma viral. A técnica de voltametria cíclica foi utilizada nas análises de reações redox na superfície do eletrodo DDB com e sem modificação de sua superfície com filme de quitosana. O composto ferroceno foi utilizado como mediador redox e indicador eletroativo de hibridização das cadeias de DNA formadas no sensor. Os picos de corrente indicaram que o eletrodo com modificação de filme de quitosana em sua superfície apresentou maior estabilidade, onde o composto redox teve maior afinidade pelas duplas cadeias hibridizadas na superfície do eletrodo, apresentando valores de correntes para DENV 1, 2, 3 e 4 de foram 0,73; 0,69; 0,79 e 1,03 μA, respectivamente. Esses valores foram superiores a corrente encontrada para o aptâmero em fita simples (ssDNA) que foi de 0,62 μA, assim como observada para corrente obtida do aptâmero hibridizado com sua fita complementar (dsDNA) cujo valor obtido foi de 0,91 μA. Análises com variações de tempo foram realizadas apresentando redução nos valores de correntes em função do tempo, provavelmente devido à redução da interação do material eletroativo no sensor. O aptasensor aqui desenvolvido apresentou boa detecção distinção entre sequências de ácidos nucleicos, apresentando potencial para aplicação na detecção do vírus da dengue.

Observando o atual interesse em polímeros organometálicos para diversas aplicações, foi feita a síntese de uma série de polímeros conjugados contendo ferroceno na cadeia principal visando à investigação de suas propriedades, em especial fenômenos magnetorresistivos, magneto-ópticos e de óxido-redução. Os polímeros preparados pelo método de McMurry foram os seguintes: PFV: poli(1,1\'-ferrocenilenovinileno) e PFV-DOPPV-M: poli[1,1\'-ferrocenilenovinileno-alt-(2,5-di-n-octilóxi)-1,4-fenilenovinileno]. Outros dois polímeros foram preparados utilizando o método de polimerização de Wittig, o PFV-DOPPV-W: poli[1,1\'-ferrocenilenovinileno-alt-(2,5-di-n-octilóxi)-1,4-fenilenovinileno] e o PFV-DMPPV: poli[1,1\'-ferrocenileno-vinileno-alt-(2,5-dimetóxi)-1,4-fenilenovinileno]. A síntese de polímeros contendo segmentos π-conjugados equenos e bem definidos separados por segmentos não-conjugados é uma das melhores stratégias para a obtenção de polímeros emissores de luz azul. Com base nesse argumento foi feita a síntese de uma série de polímeros contendo um derivado metoxilado de bisfenol-A (BPA) na cadeia principal, alternando-se com unidades de PPV ou PFV que apresentam segmentos conjugados bem definidos. Os polímeros preparados foram os seguintes: BPA-DOPPV:poli[2,2-bis(4-metoxifenil)-propano-alt-2,5-(di-n-octilóxi)-1,4-divinilbenzeno]; BPA-PPV: poli[2,2-bis(4-metoxifenil)-propano-alt-1,4-ivinilbenzeno]; BPA-DMPPV: poli[2,2-bis(4-metoxifenil)-propano-alt-2,5-dimetóxi-1,4-ivinilbenzeno]; BPA-DBPPV: poli[2,2-bis(4-metoxifenil)-propano-alt-2,5-dibromo-1,4-divinilbenzeno] e BPA-PFV: poli[2,2-bis(4-metoxifenil)-propano-alt-1,1\'-divinil-ferroceno]. Todos os polímeros obtidos foram caracterizados por métodos espectroscópicos (UV-VIS, IR, RMN), análises térmicas, SEC, entre outras. Algumas aplicações foram estudadas para esses polímeros, tais como a construção de um eletrodo de ORP modificado, a produção de diodos orgânicos emissores de luz (OLEDs) e a determinação da resposta \"olfativa\" de sensores de gases. / Owing to the current interest in organometallic polymers and their applications, a group of conducting polymers containing ferrocene in the main chain was synthesized aiming the study of their magnetoresistive, magneto-optic and redox properties. The following polymers were prepared via McMurry method: poly(1,1\'-ferrocenylenevinylene) (PFV) and poly[1,1\'-ferrocenylenevinylene-alt-(2,5-di-n-octiloxy)-1,4-phenylenevinylene] (PFV-DOPPV-M). Two other polymers were synthesized via Wittig method: poly[1,1\'-ferrocenylenevinylene-alt-(2,5-di-n-octiloxy)-1,4-phenylenevinylene] (PFV-DOPPV-W) and poly[1,1\'-ferrocenylene-vinylene-alt-(2,5-dimethoxy)-1,4-phenylenevinylene] (PFV-DMPPV). The synthesis of polymers with well-defined small π-conjugated segments separated by non-conjugated segments is one of the best strategies to obtain blue light emitting polymers. Based on this statement the synthesis of several polymers formed by methoxylated bisphenol-A (BPA) alternated with PPV or PFV units was performed. The prepared polymers were the following: poly[2,2-bis(4-methoxyphenyl)-propane-alt-2,5-(di-n-octiloxy)-1,4-divinylbenzene] (BPA-DOPPV), poly [2,2-bis(4-methoxyphenyl)-propane-alt-1,4-divinylbenzene] (BPA-PPV), poly[2,2-bis(4-methoxyphenyl)-propane-alt-2,5-dimethoxy-1,4-divinylbenzene] (BPA-DMPPV), poly[2,2-bis(4-methoxyphenyl)-propane-alt-2,5-dibromo-1,4-divinylbenzene] (BPA-DBPPV) and poly[2,2-bis(4-methoxyphenyl)-propane-alt-1,1\'-divinylferrocene] (BPA-PFV). All the synthesized polymers were characterized by spectroscopic methods (UV/VIS, IR, NMR), thermal analysis, SEC, among others. Some applications to these polymers were studied: a modified ORP electrode, organic light emitting devices (OLEDs) and gas sensors.

Title: Synthesis and catalytic properties of phosphinoferrocene guanidine Author: Ondřej Bárta Institution: Faculty of Science, Charles University in Prague, Department of Inorganic Chemistry Supervisor: prof. RNDr. Petr Štěpnička, Ph.D. Polar phosphine ligands proved to be useful in homogeneous and biphasic catalysis. Most of these phosphines bears anionic functional groups. On the other hand, functionalization of phosphines by cationic substituents is still quite uncommon, although these functional groups possess properties that could improve catalytic performance of the catalyst. In this regard, nitrogenous bases are particularly attractive due to their inherent basicity and the ability to enter into hydrogen bonding interactions. This thesis describes the synthesis of a novel ferrocene-based phosphine functionalized with guanidine moiety, viz. N-[1′-(diphenylphosphino)ferrocenylmethyl]guanidine (3). This compound was obtained by direct guanylation of 1′-(diphenylphosphino)- 1-(aminomethyl)ferrocene (2) (see scheme). Compound 3 was further used to prepare palladium complexes including the unusual zwitterionic complex [PdCl3(3H)]. The molecular structures of the prepared complexes were determined by X-ray diffraction analysis. Catalytic properties of phosphine 3 and complex [PdCl3(3H)] were...

Le développement d'architectures moléculaires enchevêtrées (rotaxanes) est un sujet d'actualité en chimie supramoléculaire. Cette thèse examine la synthèse multi-étape de sous-unités de rotaxanes, notamment de composants macrocycliques électroactifs, et leur assemblage dans des structures moléculaires imbriquées. De nouveaux cycles à 31 et 35 chaînons à liaison hydrogène comprenant un motif récepteur bis (2,6-diamidopyridine) et une unité électroactive, à savoir du ferrocène ou de la triphénylamine, ont été synthétisés. Ces macrocycles ont été analysés par voltampérométrie cyclique, analyse par diffraction des rayons X sur cristal unique, ainsi que par spectroscopie RMN et spectrométrie de masse. Les interactions hôte-invité avec un acide complémentaire 5,5’-diéthylbarbiturique (Barbital) en tant qu’invité modèle ont également été étudiées par titrage spectroscopique par absorption électronique et RMN 1H. Les affinités de liaison étaient corrélées à la structure moléculaire. Des approches pour former des [2]rotaxanes, notamment en utilisant une réaction de matrice métallique active, où l'ion métallique joue le double rôle de matrice et de catalyseur, sont décrites. En particulier, les réactions de couplage de Huisgen ainsi que de Glaser catalysées au cuivre(I) ont été utilisées avec des bouchons de volumes variés. Dans une deuxième approche complémentaire de type "attache" de la formation de rotaxane, l'anneau électroactif a été formé directement entourant le composant de filetage servant de modèle. Cette méthodologie a permis d'obtenir deux [2] rotaxanes inédits via une réaction de "clipping" à cinq composants assistée par matrice, l'un des rotaxanes intégrant deux unités de ferrocène, tandis que l'autre comprenait deux unités de type triphénylamine. Les études de diffraction des rayons X sur cristal unique ont confirmé le caractère imbriqué des assemblages. / Development of interlocked molecular ring-on-thread architectures (rotaxanes) represents a central current topic in supramolecular chemistry. This thesis considers the multi-step synthesis of rotaxane subcomponents, notably electroactive macrocyclic components, and their assembly into interlocked molecular structures. Novel hydrogen-bonding 31- and 35-member rings comprising a bis(2,6-diamidopyridine) receptor motif and an electroactive unit, namely ferrocene or triphenylamine, were synthesized. These macrocycles were analyzed by cyclic voltammetry, single crystal X-ray diffraction analysis, as well as NMR spectroscopy and mass spectrometry. Host-guest interactions with a complementary 5,5’-diethylbarbituric acid (Barbital) as model guest were also studied by electronic absorption and 1H-NMR spectroscopic titrations. Binding affinities were correlated to molecular structure. Approaches to form 2rotaxanes, notably by employing an active metal template reaction, where the metal ion plays the dual role of template and catalyst, are described. In particular, the copper(I)-catalyzed Huisgen as well as Glaser coupling reactions were employed with a variety of bulky stopper groups. In a second complementary “clipping”-type approach to rotaxane formation, the electroactive ring was directly formed encircling the templating thread component. This methodology yielded two further novel [2]rotaxanes via a template-assisted five-component clipping reaction, one rotaxane integrating two ferrocene units while the other comprised two triphenylamine-like units. Single crystal X-ray diffraction studies confirmed the interlocked nature of the assemblies.

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