Ce travail est consacré au développement d'une approche électrochimique permettant de préparer, à base de formes allotropiques différentes du carbone, divers matériaux poreux ayant comme : i) leurs éléments (feuillets de graphite, graphène, nanotubes et fullerène C60) sont attachés entre eux de façon covalente par les chaînes d'atomes du carbone de longueur différents, ii) les larges espaces internes (interstices ou les pores aléatoires) pouvant accommoder les cations, premièrement de métaux, plus grandes que Li+ (K+, Mg2+, mais aussi Alk4N+ etc.), iii) flexibilité tout en gardant la stabilité chimique des formes du carbone utilisées pour leur assemblage. Ainsi, une structure lamellaire à multicouches a été élaborée, une sorte du "graphite artificiel" avec les distances interstitielles à la demande : de 4.48 Å (avec -CH2- comme l'espaceur entre les couches) a 5.15 Å (avec -CH2C≡C-), contre 3.35 Å dans le graphite naturel. Élaborée dans ce travail, la méthode d'assemblage des matériaux stratifiés à base du graphite/graphène s'appuie sur le nouveau paradigme de greffage électrochimique aux interfaces carbonées (greffage électrophile, permettant de fixer à l'interface le linkeur CH2I ou CH2Br), et la fixation radicalaire d'une couche suivante par la réduction mono-électronique de sa liaison C-Hal. Les agents d'assemblage, Me3SiCH2I ou Me3SiC≡CCH2Br, dans un milieu universel CH3CN/0.1 M Bu4NPF6 ont été montrés être très efficaces pour ce processus. Un autre agent de couplage, 1,5-dibromopentane, a été utilisé pour assemblage cathodique (nucléophile/radicalaire) des nano-formes du carbone entre eux pour donner les matériaux poreux sans une structure spécifique régulière, les "nano-mousses", potentiellement convenable pour les anodes des batteries aux ions de Li et les batteries "post-Li-ions". Par la méthode combinée anodique/cathodique en utilisant Me3SiCH2I comme l'agent de fixation, un silsesquioxane F-@Ph8T8 avec l'ion fluorure encapsulé a été immobilisé sur le carbone vitreux ; l'interface ainsi préparée a montré son potentiel pour la détection d'exposition aux ions de Li+ ou de H+. Les structures préparées ont été étudiées par la voltampérométrie cyclique, chronocoulométrie, la spectroscopie d’impédance électrochimique et la spectroscopie électronique à balayage. / This work is dedicated to the development of an electrochemical approach to prepare, starting from different allotropic forms of carbon, various porous materials having particular features: i) their constituting elements (graphite sheets, graphene, nanotubes and fullerene C60) are covalently attached between them by the chains of carbon atoms of different length, ii) their large internal spaces (interstices or random pores) can accommodate the cations, - primarily metals, - larger than Li+ (e.g. K+, Mg2+, and also Alk4N+ etc.), iii) they are flexible while keeping the chemical stability of the carbon forms used for their assembly. Thus, a multilayered lamellar structure was developed, a kind of “artificial graphite” with interstitial distances on demand: from 4.48 Å (with -CH2- as the linker) to 5.15 Å (with -CH2C≡C-), against 3.35 Å in natural graphite. The method of assembly of graphite/graphene-based laminated materials developed in this work is based on the new electrochemical paradigm of grafting to carbon interfaces (electrophilic grafting, making possible to fix the CH2I or CH2Br functions at the interface) and the radical grafting of the subsequent layer by the mono electronic reduction of their C-Hal bond. New coupling agents, Me3SiCH2I or Me3SiC≡CCH2Br, in a universal CH3CN/0.1M Bu4NPF6 medium, have been shown to be very effective for this process. Another coupling agent, 1,5-dibromopentane, was used for cathodic (nucleophilic/radical) assembling of carbon nano forms between them to give porous materials without a regular specific structure, the “nano-sponges”, potentially suitable for making the anodes of Li-ion batteries and “post-Li-ion” batteries. Using the combined anodic/cathodic grafting method using Me3SiCH2I as the fixing agent, the fluoride encapsulating silsesquioxane F-@Ph8T8 was immobilized on glassy carbon; the thus prepared interface has shown its promise for devices detecting the exposure to Li+ or H+ ions. The prepared structures were studied by cyclic voltammetry, chronocoulometry, electro-chemical impedance spectroscopy and scanning electron spectroscopy.

Nucleophilic substitution reactions of alkylamines, cyclic alkylamines, and hydroxyalkylamines with 5-substituted-1,4-naphthoquinones have been studied. It has been found that the nature of the solvent employed in the reaction influences the position of mono-substitution at either the 2- or 3-position. Although both regioisomers were produced in all the reactions, protic polar solvents favoured the formation of the 3-regioisomer, whereas non-protic solvents favoured the formation of the 2-regioisomer. It has also been found that formation of 2,3-diaminoalkyl derivatives is normally unlikely. A series of hydroxyalkylamino-1,4-naphthoquinones were also synthesised. The collision-induced dissociation mass spectra of protonated hydroxyalkylamino-1,4- naphthoquinones showed fragmentation patterns which were dependent on the nature and length of the side chain and the presence and nature of the adjacent group on the 3-position on the 1,4-naphthoquinone ring. A total of 27 novel compounds were synthesised during the course of this research, the structures of which were confirmed via 1D and 2D NMR spectroscopy, mass spectrometry (ESI), IR spectroscopy and high resolution mass spectrometry (HRESIMS and HREIMS).

<p> In or der to study the mechanism of their conversio~ into hydrazides and thiohydrazides, a number of hydrazidic halides were treated with compounds containing a nucleophilic oxygen or sulfur atom. </p> <p> The initial products of these reactions were formed from the displacement of the (alpha)-halogen atom of the hydrazidic halide. In cases where there was sufficient activation the group attached to oxygen or sulfur was transferred to nitrogen in the presence of base. </p> <p> Some hydrazides and thiohydrazides containing displace-able groups in the 2-position of an N-aryl ring yielded benzoxadiazines and benzothiadiazines respectively under basic conditions. The reactions exhibited the characteristics of bimolecular nμcleophilic aromatic substitutions. The synthesis of four novel heterocyclic ring systems is described. </p> / Thesis / Doctor of Philosophy (PhD)

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La synthèse tout-en-un de 4-quinolones et d'indoxyles a été réalisée par couplage de Sonogashira carbonylant suivi d'une cyclisation. Une étude en catalyse homogène a révélé que les catalyseurs présents contrôlaient la sélectivité vers l'un ou l'autre des composés. Si la première étape est pallado-catalysée, l'étape de cyclisation est catalysée par des nucléophiles organiques. Ainsi, des 4-quinolones ont été préparées par multi-catalyse {[Pd]+amine} et des indoxyles par catalyse tandem {[Pd]/phosphine}. Les systèmes catalytiques ont été hétérogénéisés par fonctionnalisation de silices mésoporeuses de type SBA. Deux stratégies ont été utilisées pour contrôler la localisation de la fonctionnalité. Différents complexes de Pd ont été intégrés dans les pores du matériau par greffage post-synthétique ou dans les murs par synthèse directe. Plusieurs amines et une phosphine ont été immobilisées par greffage post-synthétique donnant ainsi des catalyseurs nucléophiles fonctionnalisés dans leurs pores. Les activités catalytiques de ces matériaux ont été évaluées dans la synthèse de la 2-phényl-4-quinolone et du 2-benzylidène-indoxyle. La première a été préparée dans de bons rendements et le système {[Pd]@SBA+amine@SBA} est recyclable sur 3 cycles. Tous les matériaux ont montré une lixiviation du Pd mais leur utilisation permet de diminuer la contamination en Pd du produit final comparé à un complexe homogène. L'indoxyle a été obtenu avec un système semi-hétérogène {[Pd]@SBA/PPh3}, l'utilisation de la phosphine greffée conduisant à la transformation de l'indoxyle vers le 2-benzylindole. La formation d'α-céto-amides en catalyse hétérogène via double carbonylation a aussi été étudiée / The one-pot selective synthesis of 4-quinolones and indoxyls was achieved through a carbonylative Sonogashira coupling followed by cyclization. A study in homogeneous catalysis revealed that the nature of catalysts in presence controlled the selectivity toward each compounds. Whereas the first coupling step is palladium catalyzed, the cyclizations require organic nucleophilic species. Thus, 4-quinolones were obtained by one-pot multi-catalysis {[Pd]+amine} and indoxyls by one-pot tandem catalysis {[Pd]/phosphine}. The catalytic systems were heterogenized by functionalizing mesostructured SBA silicas. Two strategies were employed aiming at a control of the localization of the functionality. Different Pd complexes were integrated in the pores of the material by post-synthesis grafting or incorporated into the walls via direct synthesis. Different amines and a phosphine were immobilized by post-synthesis grafting affording hybrid materials containing amine or phosphine catalysts in their pores. Catalytic activities of those materials were evaluated in the reaction affording 2-phenyl-4-quinolone and 2-benzylidene-indoxyl. The former was obtained in good yields and the heterogeneous catalytic system {[Pd]@SBA+amine@SBA} was recyclable over 3 runs. All hybrid materials showed Pd leaching but their uses still enables to decrease the Pd contamination of the final product compared to homogeneous complexes. The indoxyle compound was obtained in a semi-heterogeneous system {[Pd]@SBA/PPh3}, the use of the grafted phosphine providing transformation of the indoxyle toward 2-benzylindole. Formation of α-keto-amids by heterogeneously catalyzed double carbonylation was also studied

Na busca por novos materiais doadores de óxido nítrico (NO), o presente trabalho descreve o desenvolvimento de um filme à base de amido de mandioca, no qual foi incorporado um nitrosilo complexo de rutênio, e o estudo da liberação de NO nesse material. O nitrosilo complexo trans-[Ru(NH3)4(isn)NO](BF4)3 (RuNOisn; isn = isonicotinamida) apresenta a propriedade de liberar NO de forma controlada, por meio de fotólise (&lambda;irr = 310-370 nm) e de redução química. A incorporação desse complexo em filmes de amido foi realizada em condições brandas, resultando em um novo material para o armazenamento e liberação de NO, designado como CSx-RuNOisn. Os ensaios espectroscópicos indicaram que a esfera de coordenação do complexo RuNOisn permaneceu inalterada durante a produção dos filmes. A exposição de CSx-RuNOisn à luz (&lambda;irr = 355 nm) levou à liberação de NO e provavelmente à formação do fotoproduto trans [RuIII(NH3)4isn(H2O)]3+ no filme. A reação desse aquocomplexo de rutênio(III) com solução aquosa contendo nitrito de sódio regenerou o complexo de partida, RuNOisn. A identificação e quantificação do NO liberado durante a fotólise foi efetuada por meio da reação com oximioglobina. Durante o tempo de irradiação de 17 minutos, foram liberados 5,02 &plusmn; 0,12 &mu;M de NO (10, 04 &plusmn; 0,24 nmol NO em 2 mL). Os ensaios de liberação de NO desencadeada por redução foram realizados utilizando-se L-cisteína como redutor. O fluxo de NO liberado a partir da reação com cisteína perdurou por mais de 7 horas, alcançando-se concentrações fisiologicamente relevantes, com fluxo médio de 1,9 pmol NO s-1 cm-2 de filme. Esse valor é comparável àquele produzido por células endoteliais, em que o fluxo de NO é de 1,67 pmol s-1 cm-2. Os resultados preliminares de degradação dos filmes in vivo sugerem que o material foi degradado pelo organismo em 30 dias. Todos os resultados alcançados sugerem que o filme CSx-RuNOisn é um candidato promissor para aplicações em meio biológico. Um novo complexo de rutênio contendo o ligante nitrosilsulfito (N(O)SO3 -) foi isolado, trans [Ru(NH3)4(isn)(N(O)SO3)](X) (isn = isonicotinamida, X = PF6- ou SiPF6 2-), e a sua estrutura cristalina determinada por difração de raio-X. A síntese desse complexo foi realizada por meio da reação entre trans-[Ru(NH3)4(isn)(NO)]3+ e íons sulfito (SO32-). O ataque nucleofílico do SO32- ocorreu no nitrogênio do ligante nitrosônio (NO) coordenado ao centro metálico de rutênio ([Ru-NO+]), originando o ligante O=N-SO3-: [RuNO+]3+ + SO32- &rarr;[Ru(N(O)SO3)]+. Observou-se que em meio aquoso, no intervalo de pH de 7,4 a 5,2 o complexo trans [Ru(NH3)4(isn)(N(O)SO3)]+ é estável, e a velocidade de decomposição (labilização do ligante isn) variou de k = 0,86 a 3,07 × 10-5 s-1. Em soluções mais ácidas (tampão ácido acético/acetato pH 4,2, 3,9, ou 1,0 M ácido trifluoroacético) o complexo trans-[Ru(NH3)4(isn)(N(O)SO3)]+ decompõe-se formando o respectivo nitrosilo complexo trans- [RuII(NH3)4(isn)NO+]3+. A reação do íon trans-[Ru(NH3)4(isn)(N(O)SO3)]+ com íons hidróxido (OH-) dá origem ao respectivo nitro complexo trans-[Ru(NH3)4(isn)(NO2)]+, que foi caracterizado por RMN de 15N e por espectroscopia eletrônica. As constantes de velocidade para essa reação são k = 6,16 &plusmn; 0,22 M-1 s-1 à T = 25oC, e k = 2,15 &plusmn; 0,07 M-1 s-1 à T = 15oC. A reação entre o nitrosilo complexo trans [RuII(NH3)4(isn)NO+]3+ e íons OH- também resulta na formação do nitro complexo trans-[Ru(NH3)4(isn)(NO2)]+. Neste caso, a constante de velocidade foi estimada entre k = 47-58 M-1 s-1 à T = 25oC, e o valor obtido experimentalmente à T = 15oC foi de k = 10,53 &plusmn; 0,29 M-1 s-1. O espectro eletrônico do íon complexo trans [Ru(NH3)4(isn)(N(O)SO3)]+ em meio aquoso apresentou uma banda larga com &lambda; max = 362 nm (&epsilon; &sim;6000 M-1 cm-1), atribuída por cálculos teóricos às seguintes transições: transferência de carga do metal para o ligante (TCML) Ru &rarr; N(O)SO3 e Ru &rarr; isn, e também d &rarr; d. Os ensaios preliminares de fotólise (&lambda; irrad = 355 nm) do complexo trans[Ru(NH3)4(isn)(N(O)SO3)](PF6) em solução de tampão fosfato (pH 7,4) sugerem a formação das seguintes espécies nos intervalos iniciais de fotólise: i) NO, ii) SO3 &bull;-, e iii) isn (labilizado do complexo). O mecanismo para a formação desses produtos ainda está sob investigação. / Aiming the production of new nitric oxide releasing materials (NORM), this work reports the development of a cassava starch based film, in which a ruthenium nitrosyl complex was impregnated, and evaluate the NO release from this film. Ruthenium nitrosyl complex trans-[Ru(NH3)4(isn)NO](BF4)3 (RuNOisn; isn = isonicotinamide) is able to release NO in a controlled manner through both photolysis (&lambda;irr = 310-370 nm) and chemical reduction. The incorporation of such complex into the starch-based films was performed under mild conditions, yielding a new material able to store and release NO, abbreviated as CSx-RuNOisn. Spectroscopic analysis of CSx-RuNOisn indicated that the coordination sphere of RuNOisn remained intact during film production. Exposure of CSx-RuNOisn to long wave UV-light (&lambda;irr = 355 nm) leads to NO release and likely to the formation of the paramagnetic photoproduct trans-[RuIII(NH3)4isn(H2O)]3+ in the film. Reaction of this aquoruthenium(III) complex with aqueous nitrite regenerates RuNOisn in the film. Delivery of NO upon photolysis of CSx-RuNO isn was verified and quantified by trapping with oxymyoglobin. The calculated concentration of NO released from the film was 5.02 &plusmn; 0.12 &mu;M (10.04 &plusmn; 0.24 nmol NO in a 2 mL) after approximately 17 min of irradiation (500 laser pulses at 2 s intervals). Moreover, NO release upon chemical reduction was carried out using L-cysteine as a reductant. Cysteine-mediated NO delivery from CSx-RuNOisn persisted for more than 7 h, during which physiologically relevant NO concentrations were liberated (average flux of 1.9 pmol NO s-1 cm-2 of film). This value is comparable to that produced by endothelial cells (1.67 pmol s-1 cm-2). Preliminary results about the biodegradation of the films in vivo suggest that the films were completely absorbed by the organism in a period of 30 days. These results suggest that CSx-RuNOisn is a promising candidate for use in biological applications. A new nitrosylsulphito complex bearing the ligand (N(O)SO3-) was isolated, trans-[Ru(NH3)4(isn)(N(O)SO3)](X) (isn = isonicotinamide, X = PF6- or SiPF6-), and its structure was determined by X-Ray crystallography. This complex was obtained by the reaction between trans-[Ru(NH3)4(isn)(NO)]3+ and sulfite ions (SO32-). X-Ray results confirmed that the nucleophilic attack of the sulphite anion (SO32-) was on the nitrogen atom of the nitrosyl ligand (NO) coordinated to the ruthenium center ([Ru-NO+]), yielding the ligand O=N-SO3-: [RuNO+]3+ + SO32- &rarr; [Ru(N(O)SO3)]+. Complex trans- [Ru(NH3)4(isn)(N(O)SO3)]+ is stable in aqueous solution from pH 7.4 to 5.2, and the decomposition rates (k) (due to the isn labilization) are in the range of k = 0.86-3.07 × 10-5 s-1. In more acidic conditions, (acetate buffer pH 4.2, 3.9, and trifluoroacetic acid solution 1.0 M) complex trans-[Ru(NH3)4(isn)(N(O)SO3)]+ is converted into the respective nitrosyl trans-[RuII(NH3)4(isn)NO+]3+. Reaction of trans-[Ru(NH3)4(isn)(N(O)SO3)]+ and hydroxide ions (OH-) yielded the nitro complex trans-[Ru(NH3)4(isn)(NO2)]+, which was characterized by 15N NMR and electronic spectroscopy. Rate constants for such reaction are k = 6.16 &plusmn; 0.22 M-1 s-1 at 25oC, and k = 2.15 &plusmn; 0.07 M-1 s-1 at 15oC. In the case of complex trans-[RuII(NH3)4(isn)NO+]3+, its reaction with OH- also yield the nitro complex trans-[Ru(NH3)4(isn)(NO2)]+. The estimated rate constant for such reaction was k = 46.9-57.6 M-1 s-1 at 25oC, and the experimental value obtained at 15oC was k = 10.53 &plusmn; 0.29 M-1 s-1. The ion complex trans-[Ru(NH3)4(isn)(N(O)SO3)]+ showed an intense and broad band at 362 nm (&epsilon;&sim;6000 M-1 cm-1) in aqueous solutions, which was assigned by DFT calculations to the following transitions: metal to ligand charge transfer (MLCT) Ru&rarr;N(O)SO3 and Ru&rarr;isn, and d&rarr;d as well. Preliminary photolysis assays (&lambda;irrad = 355 nm) performed with complex trans-[Ru(NH3)4(isn)(N(O)SO3)](PF6) in phosphate buffer solution (pH 7,4) suggests that the following species have been formed (in the initial photolysis period): i) NO, ii) SO3&bull;-, and iii) isn (labilized). The whole mechanism to yield such products is still under investigation.

Dans ce travail, il est montré que les alkyl/vinyl/aryl lithiens et magnésiens réagissentavec les acides C-1(F/OMe) naphtoïques en l'absence de catalyseur métallique. Cette nouvelleréaction de substitution nucléophile aromatique permet potentiellement de préparer n’importequel biaryle tout en s'affranchissant des étapes de protection et de déprotection de la fonctionacide (CO2H). Les alkyllithiens linéaires et ramifiés réagissent avec la même efficacité que lesalkylmagnésiens même à basse température (–78 °C). Le déplacement d'un fluor ou d'unméthoxy s'effectue avec la même facilité. L'absence d'ortho-lithiation est confirmée par lepiégeage du milieu réactionnel en fin de réaction par l'iodométhane (après addition de n-BuLi,s-BuLi et t-BuLi). Le bromure de vinylmagnésium requiert un chauffage au reflux du THF.La méthode étudiée permet de préparer extrêmement facilement des 1- et 2-phénylnaphtalènes, 1,1’-binaphtalènes et 2,2’-binaphtalènes. Dans les exemples où lesaryllithiens donnent des rendements moyens-faibles en produits de couplage, les réactifs deGrignard sont beaucoup plus efficaces. Le o-tolyllithium, le bromure de o-tolylmagnésium, lebromure de (4-méthoxyphényl)magnésium, le bromure de (2,5-diméthylphényl)magnésium etle bromure de benzo[d][1,3]dioxol-5-ylmagnésium déplacent facilement le groupefluoro/méthoxy en ortho du groupe CO2M pour donner les produits de substitutioncorrespondants alors que la réaction du bromure de (2,6-diméthoxyphényl)magnésium estmoins efficace sans doute en raison de l'encombrement stérique causé par les deux groupesortho-méthoxy. L'acide 1-(2-méthoxyphényl)-2-naphtoïque est un produit particulièrementintéressant. La déprotection du groupe méthoxy suivie d'une cyclisation est réalisée par BBr3pour donner la 6H-naphtho[2,1-c]chromén-6-one qui est isolée avec un rendement de 97 %.Cette lactone est utile pour la préparation de composés atropoisomères optiquement actifsaprès ouverture énantiosélective du cycle lactone selon la technique mise au point parBringmann. / Alkyl as well as aryl substitution can be readily accomplished in generally excellentyields via a nucleophilic mode by displacement of an ortho-fluoro or methoxy group inunprotected naphthoic acids with lithium and Grignard reagents in the absence of a metalcatalyst.Alkyllithium reagents typically gave good-to-excellent yields, whether primary,secondary, or tertiary at –78 °C. Displacement of a fluoro or a methoxy group occurs withequal efficacy. The absence of ortho-lithiation was confirmed by quenching the reactionproduct with MeI after addition of n-BuLi, s-BuLi and t-BuLi. Alkyl Grignard reagentsEtMgBr and n-BuMgBr proved to be very reactive at –78 °C while vinyl magnesium bromiderequired refluxing in THF.The method provides excellent latitude with respect to the synthesis of 1- and 2-phenylnaphthalenes, 1,1’-binaphthalenes, and 2,2’-binaphthalenes. In those instances wherethe aryllithium reagents gave poor yields of coupling products, the corresponding Grignardreagents proved to be much more effective. o-Tolyllithium, o-tolylmagnesium bromide, (4-methoxyphenyl)magnesium bromide, (2,5-dimethylphenyl)magnesium bromide andbenzo[d][1,3]dioxol-5-ylmagnesium bromide smoothly displaced the fluoro/methoxy grouportho to the CO2M group to give the corresponding substitution products while reaction of(2,6-dimethoxyphenyl)magnesium bromide proceeded with less efficiency presumably due tosteric effects imparted by the two ortho-methoxy groups. Particularly useful is 1-(2-methoxyphenyl)-2-naphthoic acid which allows for further elaboration after the coupling isperformed. Deprotection of the methoxy group followed by cyclization was realized withBBr3 to afford 6H-naphtho[2,1-c]chromen-6-one which was isolated in 97% yield. Thislactone is the starting building block for the preparation of optically active atropisomers byenantioselective ring opening.

Na busca por novos materiais doadores de óxido nítrico (NO), o presente trabalho descreve o desenvolvimento de um filme à base de amido de mandioca, no qual foi incorporado um nitrosilo complexo de rutênio, e o estudo da liberação de NO nesse material. O nitrosilo complexo trans-[Ru(NH3)4(isn)NO](BF4)3 (RuNOisn; isn = isonicotinamida) apresenta a propriedade de liberar NO de forma controlada, por meio de fotólise (&lambda;irr = 310-370 nm) e de redução química. A incorporação desse complexo em filmes de amido foi realizada em condições brandas, resultando em um novo material para o armazenamento e liberação de NO, designado como CSx-RuNOisn. Os ensaios espectroscópicos indicaram que a esfera de coordenação do complexo RuNOisn permaneceu inalterada durante a produção dos filmes. A exposição de CSx-RuNOisn à luz (&lambda;irr = 355 nm) levou à liberação de NO e provavelmente à formação do fotoproduto trans [RuIII(NH3)4isn(H2O)]3+ no filme. A reação desse aquocomplexo de rutênio(III) com solução aquosa contendo nitrito de sódio regenerou o complexo de partida, RuNOisn. A identificação e quantificação do NO liberado durante a fotólise foi efetuada por meio da reação com oximioglobina. Durante o tempo de irradiação de 17 minutos, foram liberados 5,02 &plusmn; 0,12 &mu;M de NO (10, 04 &plusmn; 0,24 nmol NO em 2 mL). Os ensaios de liberação de NO desencadeada por redução foram realizados utilizando-se L-cisteína como redutor. O fluxo de NO liberado a partir da reação com cisteína perdurou por mais de 7 horas, alcançando-se concentrações fisiologicamente relevantes, com fluxo médio de 1,9 pmol NO s-1 cm-2 de filme. Esse valor é comparável àquele produzido por células endoteliais, em que o fluxo de NO é de 1,67 pmol s-1 cm-2. Os resultados preliminares de degradação dos filmes in vivo sugerem que o material foi degradado pelo organismo em 30 dias. Todos os resultados alcançados sugerem que o filme CSx-RuNOisn é um candidato promissor para aplicações em meio biológico. Um novo complexo de rutênio contendo o ligante nitrosilsulfito (N(O)SO3 -) foi isolado, trans [Ru(NH3)4(isn)(N(O)SO3)](X) (isn = isonicotinamida, X = PF6- ou SiPF6 2-), e a sua estrutura cristalina determinada por difração de raio-X. A síntese desse complexo foi realizada por meio da reação entre trans-[Ru(NH3)4(isn)(NO)]3+ e íons sulfito (SO32-). O ataque nucleofílico do SO32- ocorreu no nitrogênio do ligante nitrosônio (NO) coordenado ao centro metálico de rutênio ([Ru-NO+]), originando o ligante O=N-SO3-: [RuNO+]3+ + SO32- &rarr;[Ru(N(O)SO3)]+. Observou-se que em meio aquoso, no intervalo de pH de 7,4 a 5,2 o complexo trans [Ru(NH3)4(isn)(N(O)SO3)]+ é estável, e a velocidade de decomposição (labilização do ligante isn) variou de k = 0,86 a 3,07 × 10-5 s-1. Em soluções mais ácidas (tampão ácido acético/acetato pH 4,2, 3,9, ou 1,0 M ácido trifluoroacético) o complexo trans-[Ru(NH3)4(isn)(N(O)SO3)]+ decompõe-se formando o respectivo nitrosilo complexo trans- [RuII(NH3)4(isn)NO+]3+. A reação do íon trans-[Ru(NH3)4(isn)(N(O)SO3)]+ com íons hidróxido (OH-) dá origem ao respectivo nitro complexo trans-[Ru(NH3)4(isn)(NO2)]+, que foi caracterizado por RMN de 15N e por espectroscopia eletrônica. As constantes de velocidade para essa reação são k = 6,16 &plusmn; 0,22 M-1 s-1 à T = 25oC, e k = 2,15 &plusmn; 0,07 M-1 s-1 à T = 15oC. A reação entre o nitrosilo complexo trans [RuII(NH3)4(isn)NO+]3+ e íons OH- também resulta na formação do nitro complexo trans-[Ru(NH3)4(isn)(NO2)]+. Neste caso, a constante de velocidade foi estimada entre k = 47-58 M-1 s-1 à T = 25oC, e o valor obtido experimentalmente à T = 15oC foi de k = 10,53 &plusmn; 0,29 M-1 s-1. O espectro eletrônico do íon complexo trans [Ru(NH3)4(isn)(N(O)SO3)]+ em meio aquoso apresentou uma banda larga com &lambda; max = 362 nm (&epsilon; &sim;6000 M-1 cm-1), atribuída por cálculos teóricos às seguintes transições: transferência de carga do metal para o ligante (TCML) Ru &rarr; N(O)SO3 e Ru &rarr; isn, e também d &rarr; d. Os ensaios preliminares de fotólise (&lambda; irrad = 355 nm) do complexo trans[Ru(NH3)4(isn)(N(O)SO3)](PF6) em solução de tampão fosfato (pH 7,4) sugerem a formação das seguintes espécies nos intervalos iniciais de fotólise: i) NO, ii) SO3 &bull;-, e iii) isn (labilizado do complexo). O mecanismo para a formação desses produtos ainda está sob investigação. / Aiming the production of new nitric oxide releasing materials (NORM), this work reports the development of a cassava starch based film, in which a ruthenium nitrosyl complex was impregnated, and evaluate the NO release from this film. Ruthenium nitrosyl complex trans-[Ru(NH3)4(isn)NO](BF4)3 (RuNOisn; isn = isonicotinamide) is able to release NO in a controlled manner through both photolysis (&lambda;irr = 310-370 nm) and chemical reduction. The incorporation of such complex into the starch-based films was performed under mild conditions, yielding a new material able to store and release NO, abbreviated as CSx-RuNOisn. Spectroscopic analysis of CSx-RuNOisn indicated that the coordination sphere of RuNOisn remained intact during film production. Exposure of CSx-RuNOisn to long wave UV-light (&lambda;irr = 355 nm) leads to NO release and likely to the formation of the paramagnetic photoproduct trans-[RuIII(NH3)4isn(H2O)]3+ in the film. Reaction of this aquoruthenium(III) complex with aqueous nitrite regenerates RuNOisn in the film. Delivery of NO upon photolysis of CSx-RuNO isn was verified and quantified by trapping with oxymyoglobin. The calculated concentration of NO released from the film was 5.02 &plusmn; 0.12 &mu;M (10.04 &plusmn; 0.24 nmol NO in a 2 mL) after approximately 17 min of irradiation (500 laser pulses at 2 s intervals). Moreover, NO release upon chemical reduction was carried out using L-cysteine as a reductant. Cysteine-mediated NO delivery from CSx-RuNOisn persisted for more than 7 h, during which physiologically relevant NO concentrations were liberated (average flux of 1.9 pmol NO s-1 cm-2 of film). This value is comparable to that produced by endothelial cells (1.67 pmol s-1 cm-2). Preliminary results about the biodegradation of the films in vivo suggest that the films were completely absorbed by the organism in a period of 30 days. These results suggest that CSx-RuNOisn is a promising candidate for use in biological applications. A new nitrosylsulphito complex bearing the ligand (N(O)SO3-) was isolated, trans-[Ru(NH3)4(isn)(N(O)SO3)](X) (isn = isonicotinamide, X = PF6- or SiPF6-), and its structure was determined by X-Ray crystallography. This complex was obtained by the reaction between trans-[Ru(NH3)4(isn)(NO)]3+ and sulfite ions (SO32-). X-Ray results confirmed that the nucleophilic attack of the sulphite anion (SO32-) was on the nitrogen atom of the nitrosyl ligand (NO) coordinated to the ruthenium center ([Ru-NO+]), yielding the ligand O=N-SO3-: [RuNO+]3+ + SO32- &rarr; [Ru(N(O)SO3)]+. Complex trans- [Ru(NH3)4(isn)(N(O)SO3)]+ is stable in aqueous solution from pH 7.4 to 5.2, and the decomposition rates (k) (due to the isn labilization) are in the range of k = 0.86-3.07 × 10-5 s-1. In more acidic conditions, (acetate buffer pH 4.2, 3.9, and trifluoroacetic acid solution 1.0 M) complex trans-[Ru(NH3)4(isn)(N(O)SO3)]+ is converted into the respective nitrosyl trans-[RuII(NH3)4(isn)NO+]3+. Reaction of trans-[Ru(NH3)4(isn)(N(O)SO3)]+ and hydroxide ions (OH-) yielded the nitro complex trans-[Ru(NH3)4(isn)(NO2)]+, which was characterized by 15N NMR and electronic spectroscopy. Rate constants for such reaction are k = 6.16 &plusmn; 0.22 M-1 s-1 at 25oC, and k = 2.15 &plusmn; 0.07 M-1 s-1 at 15oC. In the case of complex trans-[RuII(NH3)4(isn)NO+]3+, its reaction with OH- also yield the nitro complex trans-[Ru(NH3)4(isn)(NO2)]+. The estimated rate constant for such reaction was k = 46.9-57.6 M-1 s-1 at 25oC, and the experimental value obtained at 15oC was k = 10.53 &plusmn; 0.29 M-1 s-1. The ion complex trans-[Ru(NH3)4(isn)(N(O)SO3)]+ showed an intense and broad band at 362 nm (&epsilon;&sim;6000 M-1 cm-1) in aqueous solutions, which was assigned by DFT calculations to the following transitions: metal to ligand charge transfer (MLCT) Ru&rarr;N(O)SO3 and Ru&rarr;isn, and d&rarr;d as well. Preliminary photolysis assays (&lambda;irrad = 355 nm) performed with complex trans-[Ru(NH3)4(isn)(N(O)SO3)](PF6) in phosphate buffer solution (pH 7,4) suggests that the following species have been formed (in the initial photolysis period): i) NO, ii) SO3&bull;-, and iii) isn (labilized). The whole mechanism to yield such products is still under investigation.

Ce travail a tout d’abord porté sur la réactivité des dérivés borés puis sur la réaction de O-alkylation des alcools aromatiques. L’utilisation des composés borés est en plein essor. Ils sont employés comme partenaires de couplage dans la réaction de Suzuki et les réactions d’additions [1,4] catalysées au rhodium pour la synthèse de molécules à hautes valeurs ajoutées. La polarisation de la liaison C-B induit le caractère nucléophile de ces composés. Cette réactivité a été exploitée pour la formation de liaisons C-F par fluoration électrophile. L’utilisation de Selectfluor® comme agent de fluoration aboutit à de bons rendements. Toutefois, la nucléophilie des composés alkylborés peut être inversée par substitution nucléophile oxydante. Ainsi, une méthode créant des liaisons C-N a pu être développée et a permis la synthèse d’amides à partir de nitriles et de sels de trifluoroborates de potassium en présence de Cu(OAc)2 et BF3.OEt2. En vue de l’importance de la chimie des éthers en synthèse organique, une méthode de préparation d’éthers aryliques a été développée au laboratoire. En partant d’un système stœchiométrique en trifluorure de bore, un système catalytique impliquant du triflate de cérium a été mis au point. Afin de répondre au mieux au concept de la chimie verte, un système catalytique hétérogène, sans solvant, a été décrit. Dans ce cas, le catalyseur employé est le Nafion® NR50, facilement recyclable, sans perte d’activité, et conduisant à de bons rendements avec les alcools aliphatiques et aromatiques. Des amines aromatiques secondaires peuvent également être préparées par cette méthode / This thesis describes the study of the reactivity of boron compounds and the O-alkylation of aromatic alcohols. The use of boronic derivatives increased considerably over the past decades. There are used as cross-coupling partners in the Suzuki reaction and for 1,4 rhodium-catalyzed addition reaction. The nucleophilic nature of these compounds was induced by the C-B bond polarization. This peculiar reactivity was studied for the C-F bond formation. The use of Selectfluor® as fluorinating agent leads to good yields. Nevertheless, the polarity of the C-B bond could be reversed by oxidative nucleophilic substitution. Thus, C–N bond could be formed from nitriles and potassium trifluoroborate salts promoted by Cu(OAc)2 in the presence of BF3.OEt2. Due to the importance of ether chemistry in organic synthesis, the O-alkylation of phenol derivatives was achieved in the laboratory. From a stoichiometric amount of Lewis acid, BF3.OEt2, a catalytic system was developed involving cerium triflate. Then, the focus on green chemistry led to use a heterogeneous catalyst. Where Nafion® NR50 appears as a suitable catalyst for the ether synthesis