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Research in metal-organic frameworks (MOFs) has risen greatly in recent decades Owing to their unequaled potential tunability and structural diversity. MOFs may be described as crystalline structures composed of metal cations or clusters of cations, commonly referred to as secondary building units (SBUs), and custom-designed organic ligands. The variety of structural motifs, ligands, and SBUs that may be incorporated promote the attainment of essentially countless potential MOFs and application in numerous areas of interest, such as gas adsorption, catalysis, gas separation, and sensing. Further functionalization of MOF materials by means of post-synthetic modification(PSM)33–37 of metal clusters or organic ligands, constructing frameworks using functional ligands or metal clusters, and incorporating advantageous molecules including organometallic molecules,38–41 enzymes,42–45 metal nanoparticles (NPs),8,46–48 heteropolyacids49–51 within the pores advance the diverse number of species, including organic ligands, inorganic metal ions/clusters, and guests, used to construct MOFs materials lead to MOFs materials possessing phenomenal properties. Implementation of these materials in sensing arises from the frameworks’ characteristic ability to increase the concentration of a desired analyte to a greater degree than its overall presence within the system; imparting an inherent sensitivity to the aforementioned analyte. MOFs materials also possess the potential for selectivity for specific analytes or classes of analytes through mechanisms such as size exclusion (molecular sieving), chemically specific interactions between the adsorbate and framework, and the directed design of pore and aperture size through the selection of appropriate organic linkers or struts. Flexible azamacrocycle-based ligands are constructed through the use of pliable carboxylate pendant arms and azamacrocycles, e.g cyclen and tacn, and used in the pursuit of novel metal macrocycle frameworks (MMCF). Polyazamacrocycles represent a popular class of macrocyclic ligands for supramolecular chemistry and crystal engineering. This popularity may be due to their complexes’ high thermodynamic stability, relative kinetic inertness, basicity, transition metal-ion coordinating ability and rigid structure. Furthermore, their utilization promotes intriguing network topologies as coordination in complexes containing tetradentate azamacrocycles generally produces only two isomers differing via the coordination ligand’s conformation. The highly reported equatorial N4¬ ¬coordination of the macrocycle allows for interaction at the two vacant trans-axial positons, whilst the folded conformations permits interaction at two vacant cis positions. Azamacrocycle complexes differ from those of other classes of macrocycles due to the fact the macrocyclic cavity is commonly occupied by metal cations. Materials containing azamacrocycles have found use in applications such as bleaching and oxidative catalysis and molecular recognition. Cyclen units have reportedly been incorporated to construct pH-dependent selective receptors for copper (II), zinc(II), yttrium(III), and lanthanum(III) ions. Herein, we describe the synthesis and characterizations of a new lanthanide framework, La(C40H40N4O8)(NH2(CH2)2)NO3 or MMCF-3, which retains a vacancy in the macrocycle unit encourages the utilization of the framework as a cation receptor and precursor for heterometallic frameworks. The inclusion of azamacrocycles into MOF materials combine the characteristic high thermodynamic stability, basicity, and strong metal complexation of the macrocycles with the high porosity, surface area, and tunability of the frameworks. Full realization of the potential of Azamacrocyclic-based MOFs requires the preparation of new entrants to this class of materials that espouse various topological structures while incorporating diverse azamacrocycles. It has been shown that the hierarchical porosity associated with macrocyclic based frameworks can be obtained using this class of ligands.71,99 The development of more frameworks exhibiting this characteristic is needed to fully investigate the potential applications of MOFs retaining the vacant cavities of the azamacrocycles. Effectuation of hierarchical porosity of azamacrocyclic frameworks will broaden sensing applications, e.g. azamacrocycles have performed as receptors of anions, cations, amino acids and other analyte molecules, and provide an ideal slot to integrate open metal site into MOFs.

Les travaux entrepris au cours de cette thèse ont eu pour objectif d'élaborer de nouvelles nanoparticules magnétiques pour l'imagerie médicale. Ce manuscrit abordera la méthode de synthèse des nanoparticules, leurs caractérisations puis leur évaluation comme agent de contraste pour l'imagerie par résonance magnétique (IRM) et radio-traceur pour la scintigraphie.Dans un premier temps, nous proposerons une méthode de synthèse pour obtenir des nanoparticules magnétiques à base de polymères de coordination cyano-pontés élaborées à partir de précurseurs moléculaires de métaux de transitions et de lanthanides en utilisant des ligands cyanure pontant et stabilisées par des ligands solubles dans l'eau et biocompatibles. Nous présenterons la synthèse, les caractérisations structurales et texturales et les propriétés magnétiques de ces nano-objets de formule générale My[M'(CN)6]z @stabilisant avec M = Fe, Gd, Tb, Y, Ni, Cu ; M' = Fe, Co et stabilisant = PEGNH2, PEG400, Glu-TEG, D-Mannitol, NADG. Nous évaluerons ensuite leur potentielle pour des applications en imagerie médicale. Pour ce faire, nous discuterons de leur capacité à se comporter comme agent de contraste pour l'IRM et comme radio-traceur pour la scintigraphie ou plus précisément la tomographie par émission mono-photonique. Nous développerons une discussion sur les paramètres fondamentaux qui doivent être optimisés afin d'obtenir des nano-objets comme agents de contraste pour l'IRM et dans le but de comprendre le mécanisme de relaxivité de ces nano-objets. Enfin, nous testerons ces agents de contraste et radio-traceurs in vitro et in vivo sur le petit animal. Puis, nous évaluerons la cytotoxicité, la cinétique et les voies d'élimination, la biodistribution, la génotoxicité et la carcinogénèse des nanoparticules utilisées. / The goal of the present research is to elaborate new magnetic nanoparticles for medical imaging. This manuscript will describe the nanoparticles' synthesis method, their characterization and their evaluation as contrast agent for magnetic resonance imaging (MRI) and functional probe for scintigraphy.In a first time, we will propose synthesis processes allowing to obtain cyano-bridged coordination polymer based magnetic nanoparticles elaborated from transition metals or lanthanides molecular precursors using cyano-bridged ligands and stabilizing ligands soluble in water and biocompatible. We will introduce the synthesis, structural and textural characterizations and magnetic properties of these nano-objects with general formula My[M'(CN)6]z @stabilizer with M = Fe, Gd, Tb, Y, Ni, Cu ; M' = Fe, Co and stabilizer = PEG NH2, PEG400, Glu-TEG, D-Mannitol, NADG.In a second time, we will evaluate their potential as nanoprobles for application in medical imaging. For that, we will discuss about their capacity to act as a contrast agent for MRI and as a functional probe for scintigraphy or more specifically single photon emission computed tomography (SPECT). We will develop discussion about fundamental parameters which must be optimized to obtain contrast agent nano-objects for MRI and to understand nano-object relaxivity mechanisms. Then, we will test these contrast agents and functional probes in vitro and in vivo on mice. Also, we will evaluate the cytotoxicity, the kinetics and way of elimination, the biodistribution, the genotoxicity and the carcinogenesis of the used nanoparticles.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18235号 / 工博第3827号 / 新制||工||1586(附属図書館) / 31093 / 京都大学大学院工学研究科合成・生物化学専攻 / (主査)教授 北川 進, 教授 濵地 格, 教授 宮原 稔 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18952号 / 工博第3994号 / 新制||工||1615(附属図書館) / 31903 / 京都大学大学院工学研究科合成・生物化学専攻 / (主査)教授 北川 進, 教授 杉野目 道紀, 教授 宮原 稔 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

Les alginates, polysaccharides extraits des algues brunes, sont des copolymères à blocs linéaires formés d'unités mannuronates (M) et guluronates (G). Leur structure dépend de la source naturelle. La complexation de cations divalents ou trivalents (sauf Mg2+) par les fonctions carboxylates conduit à la formation d'un hydrogel. Pour approfondir l'étude de la formation des gels ionotropiques d'alginate, des hydrogels et des aérogels séchés en conditions supercritiques ont été caractérisés à plusieurs échelles par différentes techniques. L'analyse orbitalaire ab initio de petits complexes a montré la formation de liaisons covalentes fortes avec les métaux de transition alors que les alcalino-terreux ne mettent en jeu que des interactions électrostatiques. Selon le rapport M/G et la nature des cations, différents régimes structuraux ont pu être identifiés par des mesures SAXS (~10-200Å) : des gels fibrillaires ou formés d'agglomérats interconnectés. Les propriétés mécaniques des hydrogels et les surfaces spécifiques des aérogels correspondants sont directement reliées à ces morphologies. La présence simultanée de plusieurs métaux dans les gels peut induire des effets coopératifs dans la formation mais aussi dans les propriétés des matériaux. De nouvelles méthodes ont été mises au point pour contrôler la synthèse de gels hétéro-cationiques, en considérant les effets d'affinité.Sur la base de cette étude, des synthèses originales de matériaux fonctionnels nano-structurés ont été développées. Certains ont été construits directement dans le réseau d'alginate en exploitant les cations de gélification ; d'autres ont nécessité le sacrifice de la matrice pour former des oxydes simples ou mixtes nanocristallins. / Alginates, polysaccharides produced by brown algae, are linear block-copolymers formed by mannuronate (M) and guluronate (G) units. Their structure depends on the natural source. The coordination of divalent or trivalent cations (except Mg2+) with the carboxylate functions leads to the formation of a hydrogel. In order to get some insight in ionotropic alginate gel formation, hydrogels and supercritical dried aerogels were analysed through various characterizations at different scales. The ab initio molecular orbital analysis on small complexes revealed strong coordination-covalent bonds in the transition metal complexes, whereas only ionic interaction occurs between the alkaline-earth cations and the carboxylates. Depending on the M/G ratio and the nature of the cation, different structural regimes were identified by SAXS analysis (~10-200Å) : well-defined fibrillar gels or gels with multiple junction nature. The mechanical properties of the hydrogels and surface areas of the resulting aerogels are directly related to these morphologies. The concomitant presence of different metals in the gel can bring cooperative effect for the formation but also for the properties of the materials. New methods to control the synthesis of hetero-cationic gels were implemented, taking into account the affinity effects. On the basis of this study, we developed new nanostructured functional materials synthesis. Some were built directly in the alginate network using the gelling cations. Others needed to sacrifice the matrix to form nanocrystalline single or mixed oxides.

Les polymères de coordination (PC) présentent un intérêt tant fondamental qu'appliqué de par leur structure et composition modulables ouvrant de nouvelles perspectives au niveau des propriétés chimiques (catalyse, conversion matériaux mous-durs…) et physiques (magnétisme, optique…). L'objectif principal de ces études consiste à vérifier le transfert de la structure, méso-structure et composition du PC vers la céramique obtenue par traitement thermique. Dans ce contexte, ce manuscrit décrit des études sur la conversion de polymères de coordination obtenus à partir d'un auto-assemblage entre des métaux 4f, 5f et de la 2,5-dihydroxy-1,4-benzoquinone (DHBQ). Dans un premier temps, des méthodes de synthèses, aqueuse et anhydre en atmosphère contrôlée, ont été mises au point. Ainsi, plusieurs types de PC ont été obtenus (4f, 4f-4f, 4f-5f), les composés mixtes formant des solutions solides. Après caractérisation de ces composés, leur comportement sous traitement thermique a été étudié. Les principaux résultats montrent que les précurseurs à base de DHBQ obtenus par voie aqueuse possèdent une méso-structure micrométrique, formée par l'assemblage de sous-unités monocristallines possédant la même structure cristallographique quelle que soit la morphologie observée. L'étude de l'assemblage de cette méso-structure a permis de contrôler la morphologie du grain élémentaire (cylindre, cube, disque…) avec une très bonne distribution en taille. La mise en œuvre de systèmes anhydres en atmosphère contrôlée a permis d'accéder à une plus large gamme de paramètres micro-structuraux (surface spécifique, porosité…). Pour l'ensemble des composés de type PC, la conversion thermique en céramique n'a pratiquement pas altéré la morphologie des matériaux. Les aspects microstructuraux ont pu être contrôlés via la méthode de synthèse. / Coordination polymers (CP) are of great academic and industrial interest due to flexible structure and composition and offer prospects for original chemical (catalysis, soft-hard materials conversion…) and physical properties (magnetism, optics…). The major interest of these studies is to check the transfer of the structure, meso-structure and composition from the CP to the ceramic via a thermal treatment. In this context, this thesis describes studies on conversion of coordination polymers obtained by self-assembly of 4f and 5f metal ions with 2,5-dihydroxy-1,4-benzoquinone (DHBQ). Aqueous and anhydrous synthetic ways were developed, which yielded different kinds of CPs (4f, 4f-4f, 4f-5f) ; solid solutions were obtained with the mixed compounds. The products were characterized and their behaviour under thermal treatment was studied. The main results show that the DHBQ-based precursors obtained by aqueous way have a micrometric meso-structure, formed by the assembly of micro-crystalline subunits which all posses the same crystallographic structure. The study of the assembly of the meso-structure allowed controlling the morphology of the elementary grain (cylinder, cube, disk ...) with very good size distribution. The implementation of anhydrous systems in a controlled atmosphere allowed yielded a wider range of micro-structural parameters (surface area, porosity ...). For all CP-type compounds, the thermal conversion to ceramic has barely altered the morphology of the materials. The microstructural aspects could be controlled via the method of synthesis.

Design of targeted functional solid-state materials for desired applications remains a scientific challenge. To overcome this hurdle, numerous synthetic strategies have been devised. It has been shown that molecules and/or clusters with pre-selected shapes, molecular building blocks (MBBs), can be utilized as units of chemical construction toward a final structure composed of those units. Typically, in metal-organic structures metal-ligand directed assembly of the MBBs, via coordination chemistry in situ, leads to the final structure. The strength of the MBB formed and, consequently, the overall rigidity of the framework are essential in their use as porous materials for applications. Lack of rigidity, i.e. instability, will ultimately lead to the collapse of the open framework upon evacuation, resulting in inaccessible pores. This phenomenon has been demonstrated repeatedly in labile metal-organic materials (MOMs) constructed via flaccid metal-nitrogen coordination (MNx) between nitrogen-based ligands and metal ions. The structures of simple metal-carboxylate clusters are welldocumented, but only recently have they been targeted for the construction of MOMs. They often possess multiple metal-oxygen coordination bonds (M(CO2)x) that result in the generation of rigid nodes with fixed geometry. Our research group has utilized heterofunctional organic linkers, taking advantage of both pyridine- and carboxylate-based functions (MNy(CO2)z), which has allowed the construction of single-metal-ion-based MBBs resulting in stabile, rigid MOMs with targeted topologies. In this dissertation, I will discuss our single-metal-ion-based design strategy and the utilization of heterofunctional ligands for MNy(CO2)z coordination of single-metal ions. I have employed this strategy to specifically target threeconnected MOMs from 3,5-pyridinedicarboxylate and MNy(CO2)z coordination of various single-metal ions, especially chiral framworks such as (10,3)-a. In addition, I have explored the MOM diversity that can be obtained via various ligand modifications, including isomerism, expansion, and functionalization. I also will show that other heterofunctional ligands can be utilized to target novel MOMs, specifically via M(CO)y(CO2)z coordination, and, resultantly, I have achieved metal-ligand directed organic synthesis and mixed-metal MOMs with magnetic tunability. I have also explored applications for MOMs, including H2 storage, and studied the barriers to rotation of the H2 molecules inside MOMs using inelastic neutron scattering to better understand the MOM-H2 interactions.

The interest in metal-organic materials namely, coordination polymers and metal-organic frameworks has risen dramatically over the past few years. To a certain extent this interest is a consequence of the realization chemists have discovered how to play a form of molecular Lego® in which metal cations or metal clusters represent the bricks (or nodes) and organic ligands such as 4,4-bipyridine (bipy) or benzene-dicarboxylate represents the glue (or spacers). The "node-and-spacer" approach to self-assembly can be invoked in such a manner that a plethora of infinite architectures and discrete polyhedra can be generated from geometric principles, some of which are unprecedented in either natural or synthetic materials. The research presented within this dissertation primarily involves the use of coordination chemistry and supramolecular chemistry in the context of synthesizing metal-organic materials and deals with how subtle variations in reactants and procedures can have dramatic effects upon the materials formed. The effect of aromatic guest molecules on the crystal packing of 1D and 2D "metal-4,4`-bipyridine" coordination polymers has been addressed in terms of structural analysis and fluorescence spectroscopy. The phenomena of supramolecular isomerism resulting from the use of metal-carboxylate clusters as building blocks for a variety of metal-organic materials will be discussed. Finally, an analysis of the Host:Guest and suprasupermolecular properties of discrete nanostructures will be provided.

Metal organic framework (MOF) has emerged as a new class of porous, thermally stable material which has attracted great attention due to their wide applications in gas storage, separation, catalysis etc. Self-assembly is the operative mechanism of MOFs syntheses; however, the control of MOF self-assembly is still a challenge in the construction of predetermined, structurally well-defined MOFs. The goal of the research is to arrive at multidimensional, highly porous and functional MOFs via hierarchical assembly of smaller molecular building blocks and, at the same time, to examine the possibilities for different interesting molecular textures. This goal is to be accomplished by the knowledge of ligand coordination mode, and geometry as well as logical choices of ligands and metals from which the MOFs are to be constructed from. Preparations of novel frameworks as well as other interesting molecular architectures are highlighted with their structures characterized.