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Triazenido ions are isoelectronic to amidinato anions,[R'N C(R)=NR']- and have a broad versatility in coordination chemistry. Metal complexes including triazenido ligands find applications in various areas of chemistry. Triazenes and complexes including triazole derivatives show extensive applicability as for example in supramolecular chemistry and pharmacological compounds. This work presents deals with the study of new triazene derivatives with triazole substituents resulting from the click reactions, acting as ligands in complexes with Cu(I), Cu(II) and Au(I). The following ligands 1,3-bis(2-azidophenyl)triazene (2), 1-(methyl)-3-(2-(4-phenyl-1,2,3-triazole)triazene-N-oxide (4), 1-(phenyl)-3-(2-(4-phenyl-1,2,3-triazole)triazene (5), 1,3-bis(2-(4-phenyl-1,2,3-triazole)triazene (6) and, complexes 1,3-bis(2-azidophenyl)triazenide-κN11- triphenylphosphine-gold(I) (2a), bis-{1-(methyl)-3-[2-(4-phenyl-1,2,3-triazole-κN2)]triazenide-1-oxide-κ2N3,O}copper(II) (4b), 1-(phenyl)-3-(2-(4-phenyl-1,2,3-triazole)triazenide-κN- triphenylphosphine-κP-gold(I) (5a), 1,3-bis(2-(4-phenyl-1,2,3-triazole)triazenide-κN- triphenylphosphine-κP-gold(I) (6a), bis[1,3-bis(2-(4-phenyl-1,2,3-triazole-κN2)-μ-N3-triazenide]-κN11,κN13 copper(I)κN13,κN11´copper(I) (Cu Cu) (6b) were investigated. The compounds were characterized by IR, UV-Vis and NMR (1H e 13C) spectroscopy, low or high resolution mass spectrometry (EI, ESI, ESI(+)-TOF and ESI(-)-TOF) and X-ray diffraction on single crystal. Triazene (2) and complex (2a) exhibit intramolecular assembling through classical and non-classical hydrogen bonding. Complexes with Au(I), (2a), (5a) e (6a), the metal atom show linear coordination geometry. The metal atom in complex (6b) shows a T distorted coordination geometry, which is extended to a quadratic coordination resulting from d10 d10 interactions between Cu(I) ions. Triazene (6) and its respective complexes (6a) e (6b) exhibit intermolecular interactions of the type C−H···M. Antibacterial activity of triazene (5) and complex (5a) were assayed resulting to be inactive against the bacteria tested. / Os compostos triazenidos são isoeletrônicos a íons amidinatos [R'NH C(R)=NR'], e têm sido usados com sucesso na química de coordenação. A complexação a íons metálicos possibilita a sua aplicação em diversas áreas da química. Assim como os triazenos, os triazóis possuem vasta aplicabilidade, desde a química supramolecular até a área farmacológica. Este trabalho apresenta o estudo inédito de pré-ligantes triazenos contendo substituintes triazóis os quais foram obtidos a partir de reações de Click, e seus respectivos complexos de Cu(I), Cu(II) e Au(I). Foram sintetizados os pré-ligantes 1,3-bis(2-azidofenil)triazeno (2), 1-(metil)-3-(2-(4-fenil-1,2,3-triazol)triazeno-N-óxido (4), 1-(fenil)-3-(2-(4-fenil-1,2,3-triazol)triazeno (5), 1,3-bis(2-(4-fenil-1,2,3-triazol)triazeno (6) e os complexos 1,3-bis(2-azidofenil)triazenido-κN11-trifenilfosfina-ouro(I) (2a), bis-{1-(metil)-3-[2-(4-fenil-1,2,3-triazol-κN2)]triazenido-1-óxido-κ2N3,O}cobre(II) (4b), 1-(fenil)-3-(2-(4-fenil-1,2,3-triazol)triazenido-κN-trifenilfosfina-κP-ouro(I) (5a), 1,3-bis(2-(4-fenil-1,2,3-triazol)triazenido-κN-trifenilfosfina-κP-ouro(I) (6a), bis[1,3-bis(2-(4-fenil-1,2,3-triazol-κN2)-μ-N3-triazenido]-κN11,κN13 - cobre(I)κN13,κN11´cobre(I) (Cu Cu) (6b). Estes foram caracterizados por espectroscopia de IV, UV-Vis e RMN (1H e 13C), espectrometria de massas de baixa ou alta resolução (EI, ESI, ESI(+)-TOF e ESI(-)-TOF) e difração de raios X em monocristal. O triazeno (2) e complexo (2a) apresentam ligações de hidrogênio intermoleculares e intramoleculares do tipo clássica e não-clássica. Os complexos de Au(I), (2a), (5a) e (6a) possuem geometria de coordenação linear. O complexo (6b) apresenta uma geometria T distorcida, a qual é estendida para quadrática pela interação d10 d10 entre os átomos de Cu(I), o triazeno (6) e seus complexos (6a) e (6b) apresentam ainda ligações intermoleculares do tipo C−H···M. Foi testada a atividade antibacteriana do triazeno (5) e o complexo (5a), os quais mostraram-se inativos frente às bactérias testadas.

Le sujet de cette thèse concerne l'élaboration depolymères hydrophiles biocompatibles et fonctionnelspour la stabilisation et la bio-fonctionnalisation denanoparticules d’oxyde de fer en vue d'une utilisation entant qu’agents de contraste en imagerie par résonancemagnétique et/ou en tant que vecteurs de principesactifs ou de thérapie génique. Pour ce travail de thèse,l'objectif a été de fonctionnaliser des poly(oxyded'éthylène)s (POE) commerciaux, connus pour leurspropriétés d'hydrophilie, de biocompatibilité et defurtivité par un groupement acide phosphonique, pourchélater les nanoparticules d'oxyde de fer, et par ungroupement furane, susceptible de réagir avec desbiomolécules à fonctionnalité maléimide, facilementaccessibles, selon une réaction de Diels-Alderthermoréversible.Des POEs à extrémité acide phosphonique et àfonctionnalité furane ont été synthétisés selon deuxstratégies originales combinant des réactionsd’Atherton-Todd ou de Kabachnik-Fields et lacycloaddition 1,3-dipolaire de Huisgen, réaction dechimie « click » très efficace, orthogonale, spécifique etréalisée dans des conditions douces.Les POEs obtenus ont ensuite été greffés à la surfacede nanoparticules d’oxyde de fer selon la stratégie‘grafting onto’. L’efficacité des POEs à stabiliser lesnanoparticules d’oxyde de fer a été mise en évidence.De plus, les tests de cytotoxicité ont montré que cessystèmes sont biocompatibles. De plus, lesnanoparticules d’oxyde de fer, une fois greffées, ontconservé leurs propriétés de relaxivité autorisant leurutilisation en imagerie médicale. Enfin, l’aptitude de cesnanoparticules fonctionnalisées par des groupementsfurane à immobiliser des molécules à fonctionnalitémaléimide a été mise en évidence ainsi que lapossibilité ultérieure à libérer ces molécules sous effetd’un stimulus thermique. Ce comportement réversibleouvre des perspectives tout à fait intéressantes dans ledomaine de la vectorisation de principes actifs. / The objective of this thesis was the preparation ofbiocompatible hydrophilic functionalized polymers forthe stabilization and bio-functionalization of iron oxidenanoparticles (IONPs) for biomedical applications suchas contrast agents in magnetic resonance imagingand/or targeted drug delivery. In this work, commerciallyavailable poly(ethylene oxide)s (PEO), which havehydrophilic, biocompatibility and furtivity properties havebeen functionalized by a phosphonic acid group, thatstrong anchors on IONPs, and by a furan group that canbe coupled to maleimide-terminated biomolecules by athermoreversible Diels-Alder reaction.Phosphonic acid-terminated PEOs fonctionalized by afurane group were synthesized according to two originalstrategies combining an Atherton-Todd or a Kabachnik-Fields reaction and a 1,3-dipolar cycloaddition reaction.This latter reaction, also named ‘click’ reaction, ischaracterized by high yields, simple reaction conditions,fast reaction times, and high selectivity.These PEOs were attached to the IONPs surface usingthe 'grafting onto' strategy. The subsequent polymerstabilizedIONPs were characterized, proving thepresence of polymers on IONPs surfaces. Cytotoxicitystudies revealed that the IONPs carriers werebiocompatible. In addition, studies on the protontransverse relaxation enhancement properties of thesestabilized IONPs indicated high relaxivities in the samerange as iron oxide based commercially availablecontrast agents. Finally, polymer-stabilized IONPs weresuccessfully functionalized by maleimide-functionalizedmolecules according to the Diels-Alder reaction and thesubsequent release of these molecules via a thermalstimulus has been proven. Consequently, this type ofcontrolled-release system could be expanded to drugtherapy responding to external stimuli.

A material to function as a molecular electronic device should have a strong coupling with electrodes through appropriate and well-defined anchoring groups and have to support an effective traveling of charges via a conjugated molecular backbone. Oligo(3-hexylthiophene)s are π-conjugated molecules having large applicability in several areas of organic electronics owing interesting semiconducting properties and they also hold great promises in the field of single-molecule electronics. Polymerization methods, in principle, allow construction of long conjugated systems in a single synthetic step, however, most of them lack precision. This work uses externally initiated chain-growth Kumada Catalyst - Transfer Polycondensation (KCTP) for the synthesis of semiconductive oligo(3-hexylthiophene) wires with controllable molecular weights, low polydispersities, high regioregularities as well as with well-defined starting and end groups. In such a way, the synthetic efforts were compromised to obtain relatively easy a series of very complex molecular wires with a reasonable structural precision. To modulate the electronic function of oligomer backbones, specific charge-transfer moieties (DMA-TCBD and Fc-TCBD) were inserted as side chains or end groups. In-situ termination of KCTP with ZnCl-functionalized electron rich alkynes followed by Diederich-type click reaction resulted in the synthesis of asymmetrical oligo(3-hexylthiophene)s having thiolate-functionalized starting groups and donor-functionalized end-groups with a high degree of end-group functionalizations. Side chains of double-thiolate functionalized oligo(3-hexylthiophene)s, on the other hand, were further modified with the insertion of charge-transfer groups by post-polymerization functionalization. While the facile synthesis and modification of oligo(3-hexylthiophene)s enable the control over the molecular backbone, the specific starting and end anchoring groups allow the control over the electrode oligomer interface. To assure the formation of alligator clips between oligomer backbone and Au electrode, the optimizations including proper end-group conversion into mild counterparts followed by in-situ deprotection into thiolates and the binding abilities on gold were investigated. Finally, the conductance of bis-end functionalized oligo(3-hexylthiophene)s was preliminarily studied through oligomer backbone by Mechanically Controllable Break Junctions (MCBJs) setup and through oligomer-attached DNA origami-templated gold nanowires by individual electrical contacts. The developed KCTP-based synthetic route, at the end, presents new opportunities for the facile synthesis, the ease of modification and the feasibility of asymmetrical and side chain functionalized oligo(3-hexylthiophene) wires for needs of molecular electronics.

A material to function as a molecular electronic device should have a strong coupling with electrodes through appropriate and well-defined anchoring groups and have to support an effective traveling of charges via a conjugated molecular backbone. Oligo(3-hexylthiophene)s are π-conjugated molecules having large applicability in several areas of organic electronics owing interesting semiconducting properties and they also hold great promises in the field of single-molecule electronics. Polymerization methods, in principle, allow construction of long conjugated systems in a single synthetic step, however, most of them lack precision. This work uses externally initiated chain-growth Kumada Catalyst - Transfer Polycondensation (KCTP) for the synthesis of semiconductive oligo(3-hexylthiophene) wires with controllable molecular weights, low polydispersities, high regioregularities as well as with well-defined starting and end groups. In such a way, the synthetic efforts were compromised to obtain relatively easy a series of very complex molecular wires with a reasonable structural precision. To modulate the electronic function of oligomer backbones, specific charge-transfer moieties (DMA-TCBD and Fc-TCBD) were inserted as side chains or end groups. In-situ termination of KCTP with ZnCl-functionalized electron rich alkynes followed by Diederich-type click reaction resulted in the synthesis of asymmetrical oligo(3-hexylthiophene)s having thiolate-functionalized starting groups and donor-functionalized end-groups with a high degree of end-group functionalizations. Side chains of double-thiolate functionalized oligo(3-hexylthiophene)s, on the other hand, were further modified with the insertion of charge-transfer groups by post-polymerization functionalization. While the facile synthesis and modification of oligo(3-hexylthiophene)s enable the control over the molecular backbone, the specific starting and end anchoring groups allow the control over the electrode oligomer interface. To assure the formation of alligator clips between oligomer backbone and Au electrode, the optimizations including proper end-group conversion into mild counterparts followed by in-situ deprotection into thiolates and the binding abilities on gold were investigated. Finally, the conductance of bis-end functionalized oligo(3-hexylthiophene)s was preliminarily studied through oligomer backbone by Mechanically Controllable Break Junctions (MCBJs) setup and through oligomer-attached DNA origami-templated gold nanowires by individual electrical contacts. The developed KCTP-based synthetic route, at the end, presents new opportunities for the facile synthesis, the ease of modification and the feasibility of asymmetrical and side chain functionalized oligo(3-hexylthiophene) wires for needs of molecular electronics.

No description available.

Inspiriert von den natürlich vorkommenden Antibiotika der Gramicidin Familie und ihrer d-(alt)-l Aminosäuresequenz, die es diesen Oligopeptiden ermöglicht, eine beta–helikale Sekundärstruktur einzunehmen, war das Hauptziel dieser Arbeit die Synthese und Charakterisierung von Peptiden und diversen Pseudopeptiden mit regulärer all-l und d-(alt)-l Sequenz und die Untersuchung des Einflusses dieser stereochemischen Variation auf die Strukturen und Eigenschaften dieser Verbindungen. Zusätzlich ergab der Austausch von Amid-Bindungen im Peptid-Rückgrat durch verschiedene Isostere diverse, teils einzigartige Pseudopeptid-Strukturen, wohingegen Verzweigung des linearen Peptid-Rückgrates zu sphärischen Molekülen führte. Alle Projekte zielten auf die Entwicklung und Synthese diskreter Oligomere für Strukturuntersuchungen, sowie auf die Einbindung der jeweiligen Strukturelemente in Polymere. Die Polymerization geeigneter Monomere zu Polymeren soll zu makro- und supramolekularen Nano-Objekten führen. Die divergent/konvergente Synthese einer Serie von Oligo-d-(alt)-l-lysinen zielte auf die Generierung hydrophiler, pH-sensitiver nanotubularer Strukturen. Schrittweiser Austausch von Amid-Bindungen des Peptid-Rückgrates durch Ester-(alt)-Urea-Einheiten führte zu all-l und d-(alt)-l Oligopseudoleucinen mit 50% und 0% Amid-Bindungs-Anteil. Design, Synthese und Polymerisation von AB-“Click”-Monomeren, basierend auf all-l and l-(alt)-d lysin Dipeptiden, ergaben hochmolekulare, Triazol-enthaltende Polypseudopeptide, deren Seitenketten mit Pyrenbuttersäure quantitativ postfunktionalisiert werden konnten. Die Einführung von Verzweigung in Glutamat-Peptide ergab chirale Dendrimere mit adressierbaren fokalen und periphären Funktionalitäten, sowie variabler Ladungsdichte. Design, Synthese und Polymerisation eines Glutamat basierenden AB2-“Click”-Monomers lieferte verwandte chirale hyperverzweigte Polypseudopeptide. / Inspired by the naturally occurring antibiotics of the Gramicidin family and their d-(alt)-l amino acid sequence, enabling these oligopeptides to adopt a beta–helical secondary structure, the work presented in this thesis targeted the syn-thesis and characterization of peptides and diverse pseudopeptides with regular all-l and d-(alt)-l sequences and the influence of this stereochemical variation on the compounds’ structures and properties. Further diversification of the struc-tures as obtained by replacing amide bonds in the peptide backbone with differ-ent isosteres, affording unique pseudopeptide structures. In addition spherical molecules were generated by introducing branching into the linear peptide scaf-fold. Throughout all projects, the aim was the design and synthesis of discrete oligomers for structural investigations and the incorporation of the respective structural elements into polymers via the polymerization of suitable monomers, in order to generate nanoscale macromolecular and supramolecular objects. The divergent/convergent synthesis of a series of oligo-d-(alt)-l-lysines targeted the generation of hydrophilic, pH-sensitive nanotubular structures. The stepwise replacement of peptide backbone amide bonds with ester-(alt)-urea moieties afforded all-l and d-(alt)-l oligopseudoleucines with 50% and 0% amide content. The design, synthesis, and polymerization of an AB-“Click”-monomer, based on all-l and l-(alt)-d lysine dipeptides afforded high molecular weight, triazole con-taining polypseudopeptides. Quantitative coupling to pyrene butyric acid afforded the respective side chain labeled polymers. The introduction of branching into glutamate peptides afforded fully chiral den-drimers with addressable focal and peripheral functionalities and variable charge density. The design, synthesis, and polymerization of a glutamate based AB2-“Click”-monomer led to related chiral hyperbranched polypseudopeptides.

La présente thèse décrit la synthèse de briques de base de fullerènes pour la préparation de dispositifs moléculaires photoactifs combinant C60 et porphyrines. La cycloaddition alcyne-azoture catalysée au cuivre (I) a été utilisée comme outil de synthèse pour la préparation des dérivés C60 complexes.L’utilité synthétique de synthons C60 a été montrée avec la préparation d’édifices moléculaires complexes présentant des propriétés spécifiques pour diverses applications. Ainsi, un système photoactif flexible combinant C60 et porphyrine a été synthétisé. Cependant la flexibilité de l’espaceur liant les sous-unités de ce composé conduit à des variations de structurales importantes et complique ainsi l’analyse des études photophysiques.Dans ce contexte, nous nous sommes proposé dans une première partie de la présente thèse de parfaitement contrôler l’orientation et la distance des différentes sous-unités au sein de systèmes C60-donneurs. Afin de répondre à ce besoin, nous avons construit une brique de base de C60 rigide ayant un groupe azoture aromatique. Ainsi, la réaction « click » avec un phénylacétylène conjugué au groupement donneur conduit à un espaceur rigide entre les deux sous-unités.La deuxième partie de ce travail a été consacrée à la synthèse d’hexa-adduits du C60 portant différents groupements fonctionnels. Une méthode de synthèse permettant de préparer des hexa-adduits du C60 fonctionnalisés a été mise au point au laboratoire.Cette stratégie a été modifiée et des composés de C60 comportant dix fonctions azotures et une fonction alcyne protégée ont été synthétisés; dans ce cas il est possible d’introduire dans un premier temps par une réaction click dix groupes fonctionnels. Et dans un second temps; après déprotection de la fonction alcyne, une seconde réaction de click permet alors de greffer un fonctionnel différent. / The present PhD thesis manuscript is focused on the use of fullerene building blocks for the preparation of photoactive molecular devices combining C60 and porphyrins. Cu(I) Catalyzed alkyne-azide cycloaddition was used as a synthetic tool for the preparation of complex C60 derivatives. Specifically, in the first part (Chapter II-B), a flexible fullerene-porphyrin triad has been developed and the photophysical studies were performed. The flexible linker between the fullerene core and the azide groups prevented any conformational control on the relative orientation and distance between the two photoactive subunits connected together. This prompted the development of an analogous building block in which the azide unit is directly connected to the bridging phenyl ring (Chapter II-C). In this way, the click reaction with porphyrin-alkyne derivatives give access to hybrid systems with a controlled relative orientation of the two moieties. This is of fundamental importance for a better understanding of the structural parameters affecting the electron and/or energy transfer kinetic in such dyads.In the second part (Chapter III), a fullerene hexaadduct scaffold is used to build up sophisticated multiporphyrin systems for various applications. The preparation of these multi-chromophoric ensembles relies on the click-click approach developed in our group.