Dissertations / Theses: 'Hybrid ligands'

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Jones, Claire Frances. "Lanthanide complexes of bulky hybrid ligands." Thesis, University of Newcastle upon Tyne, 2017. http://hdl.handle.net/10443/4009.

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The synthetic and redox chemistry of lanthanide organometallic complexes has considerably expanded since the discovery of Kagan’s reagent in 1977 and divalent ionic complexes are now known for the entire lanthanide series. The synthesis, solid-state structures and reductive chemistry of trivalent and divalent lanthanide complexes with cyclopentadienyl-type ligands is reviewed with a focus on the impact of the ligand on the reducing power of the metal centre. Trimethylsilyl and more recently, phosphine-borane stabilised carbanions have facilitated the isolation of trivalent and divalent lanthanide complexes of alkyl ligands with Ln—C σ-bonds. The synthesis, structures and known reactivity of these compounds is discussed. In order to probe the impact of alkyl carbanion and cyclopentadienyl coordination on lanthanide complex stability, structure and redox reactivity we have designed a novel set of hybrid ligands that combine these two functional groups into a single dianionic ligand. These ligands are potentially very versatile as the sterics and electronics of both groups in the ligand can be modified. The ligands are viable to support sterically congested trivalent complexes for sterically induced reduction as well as metal based reduction and they are good ligands for heteroleptic complexes because they chelate the metal avoiding ligand redistribution equilibria. The synthesis and characterisation of a range of trimethylsilyl-, phosphine-borane- and phosphine-stabilised alkyl bromo- and chlorosilane precursors is described: (Me3Si)2CHSiMe2Br [4], (Me3Si){PMe2(BH3)}CHSiMe2Cl [9], (Me3Si){PnPr2(BH3)}CHSiMe2Cl [13], {PMe2(BH3)}2CHSiMe2Cl [23], {PMe2(BH3)}{PPh2(BH3)}CHSiMe2Cl [27], {PPh2(BH3)}2CHSiMe2Cl [31] and (nPr2P)2CHSiMe2Cl [32]. iv The results of a computational study using NBO methods to investigate the relative stabilising effect of each of these silyl, phosphine-borane and phosphine carbanion stabilising groups on a model system akin to the alkyl part of the hybrid ligand are described. Reaction of (Me3Si)2CHSiMe2Br with Li/Na/K Cp/Cp’/Cp4Me followed by aqueous work-up gave the hybrid proligands {(CpH)Me2Si}(Me3Si)2CH [5], {(Cp’H)Me2Si}(Me3Si)2CH [6] and {Cp4MeH)Me2Si}(Me3Si)2CH [7] as mixtures of regioisomers [Cp4Me = 1,2,3,4-Tetramethyl-cyclopentadiene]. Reaction of LiCp4Me/KCp4Me with (Me3Si){PMe2(BH3)}CHSiMe2Cl and (Me3Si){PnPr2(BH3)}CHSiMe2Cl gave the hybrid proligands (CpH4MeMe2Si)(Me3Si)CH{PMe2(BH3)} [10] and (CpH4MeMe2Si)(Me3Si)- CH{PnPr2(BH3)} [14]. The compounds {Cp4MeH)Me2Si}(Me3Si)2CH, (CpH4MeMe2Si)- (Me3Si)CH{PMe2(BH3)} and (CpH4MeMe2Si)(Me3Si)CH{PnPr2(BH3)} crystallise as solvent-free monomers with very similar molecular conformations. The hybrid pro-ligands exhibit variable moisture sensitivity. Reaction of (Me3Si){PMe2(BH3)}CHSiMe2Cl with NaCp followed by aqueous work-up and column chromatography of the oily residue obtained gave the siloxane [(Me3Si){PMe2(BH3)}HCMe2Si]2O [19] and dicyclopentadiene. Reaction of (nPr2P)2CHSiMe2Cl with NaCp followed by aqueous work-up using deoxygenated water gave (nPr2P)2CH2 in quantitative yield. The same reaction avoiding the aqueous work-up gave (CpHMe2Si)CH(PnPr2)2 [33]. Hybrid ligands were prepared by metalation of {Cp4MeH)Me2Si}(Me3Si)2CH, {(Cp’H)Me2Si}(Me3Si)2CH and {(CpH)Me2Si}(Me3Si)2CH with MeK to give the hemisolvated dipotassium salts [(CpMe2Si)(Me3Si)2C]K2(Et2O)0.5 [50], [(Cp4MeMe2Si)(Me3Si)2C]K2(Et2O)0.5 [51] and [(Cp’Me2Si)(Me3Si)2C]K2(C6H6)0.5 [52], which decomposed slowly in THF and toluene. [(Cp4MeMe2Si)(Me3Si)2C]K2(Et2O) [51.Et2O] was crystallised as an alternative solvate from diethyl ether and the v extended structure consists of chelated [(hybrid ligand)K(Et2O)]- anionic units linked nose to tail by unsolvated K cations in a non-linear (zig-zag) polymer chain. [(Cp’Me2Si)(Me3Si)2C]K2(C6H6)·C6H6 [52.C6H6] also crystallised as a monosolvate from benzene, but with addition uncoordinated solvent present in the structure. There are two distinct types of polymer chain in the structure of [(Cp’Me2Si)(Me3Si)2C]K2(C6H6)·C6H6, one is similar to the chain in [(Cp4MeMe2Si)(Me3Si)2C]K2(Et2O) and in the other half the potassium cations in this chain are coordinated by only a cyclopentadienyl ring and a benzene ring. The remainder of the K cations are sandwiched between a carbanion and cyclopentadienyl ring of different hybrid ligands, as in [(Cp4MeMe2Si)(Me3Si)2C]K2(Et2O). These chains are cross-linked by a short contact between K and the –SiMe3 substituent of the Cp’ ring. Due to their more acidic alkyl protons metalation of (CpH4MeMe2Si)(Me3Si)CH{PMe2(BH3)}, (CpH4MeMe2Si)(Me3Si)CH{PnPr2(BH3)} and (CpHMe2Si)CH(PnPr2)2 could be achieved with BnK in THF. (CpH4MeMe2Si)(Me3Si)CH{PMe2(BH3)} is isoelectronic and isosteric with {Cp4MeH)Me2Si}(Me3Si)2CH. [(Cp4MeMe2Si)(Me3Si){PMe2(BH3)}C]K2(THF) [53.THF] crystallises as a solvate from benzene/THF with a 3D polymeric network structure through multiple agostic-type B—H····K contacts. Of the two symmetry inequivalent K cations in the structure the alkyl carbanion interacts directly only with the unsolvated cations and the solvated cations are coordinated through the borane-hydrogens. Metathesis reactions of [(Cp4MeMe2Si)(Me3Si)2C]K2(Et2O)0.5 and [(Cp4MeMe2Si)(Me3Si){PMe2(BH3)}C]K2(THF)0.5 with LaI3(THF) and SmI3(THF) in THF gave [(Cp4MeMe2Si)(Me3Si)2C]LaI(THF)2 [56] and [(Cp4MeMe2Si)(Me3Si){PMe2(BH3)}C]-SmI(THF)2 [57] after extraction into diethyl ether and crystallisation from toluene/THF and diethyl ether respectively. The vi hybrid ligand bound successfully to the lanthanide metal cations. [(Cp4MeMe2Si)(Me3Si)2C]LaI(THF)2 is a monomer in the solid-state, chelated by the hybrid ligand forming pseudo-four-membered ring and two coordinating molecules of THF in addition to the iodine anion. A zwitterion structure is adopted by [(Cp4MeMe2Si)(Me3Si){PMe2(BH3)}C]SmI(THF)3 with no contact between the Sm(III) cation and the alkyl carbanion centre. The hybrid ligands have a much larger cone angle and are far more sterically bulky when chelating the lanthanide metal, as in [(Cp4MeMe2Si)(Me3Si)2C]LaI(THF)2. The metathesis reaction of [(Cp4MeMe2Si)(Me3Si)2C]K2(Et2O)0.5 with CaI2 gave [(Cp4MeMe2Si)(Me3Si){PMe2(BH3)}C]Ca(THF)2 [58] after extraction and crystallisation from diethyl ether. In this structure the phosphine-borane stabilised carbanion group of the hybrid ligand coordinates the Ca cation through the carbanion centre. Synthesis of the Yb(II) analogue, [(Cp4MeMe2Si)(Me3Si){PMe2(BH3)}C]Yb(THF)x gave an almost identical NMR spectrum, but could not be crystallised.

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2

Böhm, Marcus. "Hybrid ligands in quantum dot solar cells." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708460.

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Joly, KeÌvin. "Synthesis of novel hybrid cyclopentadienyl-amino acid ligands." Thesis, University of Birmingham, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.422784.

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Lane, Rhian Jane. "Hybrid phosphine-carbene ligands and their use in homogeneous catalysis." Thesis, Cardiff University, 2005. http://orca.cf.ac.uk/56059/.

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Several chelating phosphine-imidazolium salts have been synthesised and their activity tested in a number of palladium catalysed cross-coupling reactions. The in- situ catalyst testing was carried out using parallel screening techniques and moderate catalytic activity was shown by phosphine-imidazolium salts 2, 6 and 16. A number of synthetic routes have been successfully established which have provided viable paths into three main types of phosphine functionalised imidazolium salts. These methodologies have increased the scope for the potential number of interesting chelating phosphine-imidazolium salts. Several group 10 complexes of these new ligands have been prepared and characterised by the reaction of functionalised nucleophilic heterocyclic carbene's (NHC's), which were generated in-situ and reacted with suitable metal precursors. The solid state structure of complex 1 has been obtained, giving an insight into the properties of these chelating ligands. The relative trans influence of the phosphine and carbene functions have been measured for this bidentate ligand. Following the results of the in-situ catalyst testing, two pre-formed palladium(II) complexes, 1 and 2, were tested in the Heck and Suzuki cross-coupling with the reaction performed under stricter anaerobic conditions with more favourable results. The synthesis of several silver(I) complexes was also achieved by the reaction of phosphine- imidazolium salts with Ag2O3. The preparation of a Rh(I) phosphine-NHC complex was achieved via transmetallation.

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Staniland, Paul M. "Synthesis and characterisation of new complexes with soft donor hybrid ligands." Thesis, Loughborough University, 2007. https://dspace.lboro.ac.uk/2134/10803.

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6

McGillewie, L. "Identification of novel ligands of WDR47, using yeast two-hybrid analysis." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/3002.

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Thesis (MScMedSc (Biomedical Sciences. Molecular Biology and Human Genetics. Medical Biochemistry))--University of Stellenbosch, 2009.
The mammalian neocortex contributes to the increasing functional complexity of the mammalian brain, partly because of its striking organisation into distinct neuronal layers. The development of the neocortex has been well studied because disrupted neurodevelopment results in several human diseases. The basic principles of neocortical development have been well established for some time; however the molecular mechanisms have only recently been identified. One major advance in our understanding of these molecular mechanisms was the discovery of Reelin, an extracellular matrix protein that directs the migration of neurons to their final positions in the developing neocortex. Reelin is a large multi-domain protein that exerts its functions by binding to its ligands on the cell surface and initiating a signal transduction cascade that ultimately results in cytoskeletal rearrangements. Several investigations have been undertaken to elucidate the functions of each of these domains to gain a better understanding reelin’s functions. We have previously identified the WR40 repeat protein 47 (WDR47), a protein of unknown function, as a novel putative ligand for the N-terminal reeler domain of reelin. To gain better understanding into the functional significance of this interaction, the present study sought to identify novel WDR47- interacting proteins. In order to achieve this, a cDNA encoding a polypeptide that contains the two N-terminal domains of WDR47, i.e. the Lis homology and the C-terminal Lis homology domain (CTLH) was used as bait in a Y2H screen of a foetal brain cDNA library. Putative WDR47 ligands were subsequently verified using 3D in vivo co-localisation. Results of these analyses showed that SCG10, a microtubule destabilizing protein belonging to the stathmin family of proteins, interacted with the N-terminal of WDR47. The identification of SCG10 as a novel WDR47 interacting protein not only sheds some light on the role and function of WDR47 but also aids in a better understanding of the reelin pathway and cortical lamination. Moreover, the data presented here, may also provide researchers with new avenues of research into molecular mechanisms involved in neuronal migration disorders.

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Hu, Liangming. "Inorganic-Organic Hybrid Networks Constructed from Different Metal Ions and Ligands." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/26945.

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Hybrid inorganic-organic networks have been studied in both chemistry and materials science due to properties, (e.g. porosity, magnetic and electronic behaviors) that may lead to applications in catalysis, gas absorption and storage. It is important to understand the different structural topologies shown by hybrid networks to help develop practical applications for these materials. The research is focused on the design and synthesis of well-defined hybrid network structures that have potential to contain molecular size cavities that can be used for catalysis and gas storage. In the field of organic-inorganic hybrid networks, the goals are to design and synthesize 1D, 2D and 3D networks with cavities, and to characterize them by X-ray, TGA and surface area measurements. Twenty-six networks have been successfully made with interesting structure topologies. These hybrid network structures are classified into three series based on their ligands. Series I contains ten hybrid networks constructed from the flexible ligand, 4, 4â -trimethylenedipyridineÂ¬ (TMDP),Â¬ Zn2+ ions, and H3PO3, and with aromatic alcohols as templates to direct the formation of various hybrid network structures. Series II consists of five structures constructed from the relatively rigid ligand, 4, 4â -bisimidazolelybipyridine (BIB)Â¬Â¬ with metal ions (Cu2+, Ni2+) and the conjugated bases of H3PO3 and H3PO4. The BIB ligand is not commercially available so is produced and characterized by NMR, mass spectrometry and TGA. Rigid network structures were expected to construct with pores of molecular dimensions with the BIB ligand. To date, the BIB ligand has not yield the desired porous network, however, these 3D hybrid networks have interesting topologies, one of which is an interdigitated network that is the precursor for 3D interpenetrated networks. Series III contains five hybrid structures constructed from various organic ligands, such as tartaric acid, picolinic acid and 1, 2, 4-triazole. In addition to the hybrid networks, six hydrogen bonded networks were prepared. Graph-Analysis is applied to study these hydrogen bonded network structures. The Ï â ¦.Ï interaction is also discussed within the hydrogen bonded networks.
Ph. D.

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Bajwa, Somia Ehsan. "Hybrid multidentate phosphine-alkene ligands for transition metal coordination chemistry and catalysis." Thesis, University of York, 2012. http://etheses.whiterose.ac.uk/2633/.

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The development of a new class of phosphine-alkene and thio-phosphine-alkene ligands based on a chalcone ferrocene framework, represents the primary focus of this study. The synthesis and characterisation of novel ligands, ferrochalcone 32 and thio-ferrochalcone 33, are described. The related alkene-phosphine ligands, the Lei ligand 17 and novel thio-Lei ligand 46, are further detailed. The coordination chemistry of four ligands (17, 32, 33 and 46) with various transition metals (Pt, Pd, Cu, Rh and Au) has been investigated in a comprehensive spectroscopis study. Single crystal X-ray analysis has been conducted at suitable junctures within the project. A surprising finding was that some solution-state structures were found to be different when studied in the solid state. The AuI complexes-containing the ligands have been successfully used in 1,5-enyne cycloisomerisation reactions. In addition to the coordination chemistry of the novel ligand systems, some interesting findings emerged For example, AuI complex of Lei ligand 17 and monodbaPHOS 74 undergoes an interesting solid-state [2+2] intramolecular cycloaddition transformation, giving cycloadduct, 72 and 77. An interesting finding includes the presence of impurity in commercially available Pd(OAc)2. Cyclopalladation of papaverine was carried out using pure and impure Pd(OAc)2, which resulted in the identification of novel Pd-dimer complex, 86. The result suggest that nitrite contaminants derive from impurities in Pd(OAc)2, and not from the oxidation of acetonitrile mediated by metallic Pd0, explain the formation of PdII-nitrito cyclopalladated products. Photocrystallographic metastable linkage isomerisation and complete conversion to an oxygen-bound nitrito complex 90 was also observed.

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Reiser, Beate [Verfasser], and Tobias [Akademischer Betreuer] Kraus. "Tailored ligands for hybrid materials from colloidal inks / Beate Reiser ; Betreuer: Tobias Kraus." Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2018. http://d-nb.info/1160938687/34.

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Nassar, Roger Abdo. "Coordination of some monodentate and hybrid multidentate phosphine ligands to platinum group metals." Thesis, University of Leicester, 2000. http://hdl.handle.net/2381/30050.

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A range of low-valent late transition-metal triarylphosphine complexes have been prepared and characterised by a combination of 1H, 31P and 19F (as appropriate) NMR and IR spectroscopies and mass spectrometry. Some of these complexes have been isolated as single crystals and characterised by X-ray diffraction. The triarylphosphine ligands used in this study were P(4-CH3OC6H4)3, P(4-HOC6H4)3, P(2-CH3OC6H4)3, PPh2(2-CH3OC6H4), P(2-HOC6H4)3 and PPh2(2-C2H3C6H4) whilst the transition-metals were platinum(II), palladium(II), rhodium(I), rhodium(III), osmium(II) and ruthenium(II). This work has shown that the former four phosphine ligands act as monodentate ligands whilst the last two ligands act as hybrid multidentate ligands. The metal complexes of the ortho-hydroxy substituted ligand exhibit fluxional behaviour in solution, where the phosphine is interchanging between mono- and bi-dentate modes of coordination. In contrast, fluxionality has not been observed in the case of the ortho-vinyl substituted ligand. A set of platinum(II)-, osmium(II)- and ruthenium(II)-fluoride triarylphosphine complexes have been prepared and characterised. The electron-donating substituents in the phosphine strengthen the metal-phosphine and metal fluoride bonds as compared to those for the non-substituted triarylphosphine ligand, PPh3. Furthermore, these substituents affect the geometry at the metal centre in these complexes. In the reactions of P(2-HOC6H4)3 with [Pt(-F){P(4-CH3OC6H4)3}2]2 or [M(-F)F(CO)3]4 (M = Os, Ru), metal chelates are formed by the displacement of fluoride by phenoxide and liberation of HF, whereas, in the related reactions, the ortho-vinyl substituted ligand acted in a monodentate mode.

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Reiser, Beate Verfasser], and Tobias [Akademischer Betreuer] [Kraus. "Tailored ligands for hybrid materials from colloidal inks / Beate Reiser ; Betreuer: Tobias Kraus." Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:291-scidok-ds-272035.

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12

Bouyon, Yenda Tracy Christ. "Synthèses, analyses et applications de systèmes à base de nanoparticules hybrides Or/Thiol." Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4761.

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Cette thèse développe la synthèse contrôlée et la purification de nanoparticules d’or hybrides, AuNPs stabilisées par des thiols organiques modulant leurs propriétés de surface. Les applications visent la catalyse et le domaine biomédical, impliquant un contrôle poussé des nanoobjets introduits. Les synthèses des AuNPs organiques sont développées à partir de la méthode de Brust, avec le 4-hydroxythiophénol et le 4-méthylthiophénol. Elles conduisent à des nanoparticules hybrides stables d’environ 2 nm. Les fractions de purifications sont analysées par MET, UV-visible, RMN et ATG, caractérisant le cœur d’or, la couche de ligands et leurs interactions. Il apparaît que les AuNPs hybrides présentent un assemblage de thiols en monocouche ou en multicouche. Une nouvelle voie de synthèse directe en phase aqueuse d’AuNPs d’environ 4 nm, stabilisées par le 4-hydroxythiophénol, est ensuite développée. Ces AuNPs sont purifiées par dialyse et caractérisées par MET, UV-visible, RMN et ATG. Les fractions d’AuNPs organiques, présentant différents états de surface, sont imprégnées dans la silice mésoporeuse SBA-15. Les isothermes d’adsorption et la manométrie sous diazote indiquent une bonne dispersion des AuNPs et une insertion dans les canaux. Nous introduisons l’exploration d’applications ciblées. L’utilisation des AuNPs organiques lors de l'oxydation d’alcènes tend à améliorer la sélectivité du sel de manganèse catalytique. Pour le domaine biomédical, les AuNPs aqueuses présentent une bonne dispersibilité en milieux aqueux biocompatibles. Les premiers tests in-vitro sur des cellules de sarcomes humains montrent une faible cytotoxicité et une bonne pénétration intracellulaire
This Ph.D. work developed the controlled synthesis and purification of hybrid gold nanoparticles AuNPs, stabilized by organic thiols that are tuning their surface properties. The targeted applications are the catalysis and in the biomedical field, requiring a thorough control of the introduced nanoobjects. Syntheses of the organic AuNPs were developed from the Brust method, using 4-hydroxymercaptophenol or 4-methylmercaptophenol, leading to stable hybrid gold nanoparticles of size 2 nm. Purified fractions were characterized using TEM, UV-visible, NMR and TG analysis, issuing key data about the gold core, the organic layer and their interactions. Among the different fractions of AuNPs, the organic thiol ligands appeared to be assembled either as a monolayer or a multilayer pattern. A new direct route for synthesis of aqueous AuNPs of size 4 nm, stabilized by 4-hydroxymercaptophenol, has been developed. The AuNPs were purified using dialysis and characterized by TEM, UV-visible, NMR and TG analysis. Organic AuNPs, exhibiting different surface properties, were impregnated into SBA-15 mesoporous silica. Adsorption isotherms and nitrogen adsorption/desorption studies were in good agreement with the homogeneous distribution of AuNPs and the significant incorporation into the porosity. Finally, exploration of the targeted applications was started. The use of organic AuNPs for alkene oxidation tends to improve the selectivity of manganese salt catalyst. In the biomedical field, the aqueous AuNPs exhibited good dispersibility into biocompatible aqueous solvents. First in-vitro assays involving human sarcoma cells line showed limited cytotoxicity and good cellular uptake

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Massard, Alexandre. "Ligands hybrides : synthèse et chimie de coordination." Phd thesis, Université de Bourgogne, 2011. http://tel.archives-ouvertes.fr/tel-00704510.

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Ce manuscrit traite de la synthèse de ligands hybrides et de leur chimie de coordination. La première partie est consacrée aux ligands Cp-imidazole, Cp-imidazolium et Cp-phosphine. Plusieurs voies de synthèse ont été développées pour accéder à ces ligands mixtes. Leur chimie de coordination est également étudiée avec le titane. Dans la seconde, une technique développée au laboratoire pour synthétiser des phosphine-oléfines a été appliquée pour obtenir un ligand phosphine-diène, possédant trois sites de coordination potentiels. Avec différents métaux de transitions, nous avons étudié les modes de coordination de ce ligand hybride. Certains complexes formés ont également été testés en catalyse. Dans la troisième partie a été étudiée la chimie de coordination de bisaminophosphoniums vis-à-vis du titane. Ces ligands ont pu être coordinés à différents états de déprotonation, conduisant à des complexes cationiques ou neutres.

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Han, Guoxia. "Design, synthesis, pharmacology, and structural analysis of bioactive melanocortin receptors' ligands by hybrid approaches." Diss., The University of Arizona, 2000. http://hdl.handle.net/10150/284287.

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A number of alpha-melanotropin (α-MSH) analogues have been designed de novo, synthesized and bioassayed at different melanocortin receptors from frog skins, mice and humans. These ligands were designed from two scaffolds, Somatostatin and Deltorphin-II, by two new hybrid approaches, one of which utilizes the modified cyclic structure (H-DPhe-Cys---Cys-Thr-NH₂) of a Somatostatin analogue--Sandostatin®, while the other incorporates the hydrophobic tail of Deltorphin-II (Glu-Val-Val-Gly-NH₂). Some of the ligands designed, H-DPhe-c [XXX-YYY-ZZZ-Arg-Trp-AAA]-Thr-NH₂ [XXX and AAA = Cys, DCys, Pen, DPen; YYY = His, His(1-Me), His(3-Me); ZZZ = Phe and side chain halogen substituted Phe, DPhe, DNal(1') and DNal(2 ')] and c[XXX-YYY-ZZZ-Arg-Trp-Glu]-Val-Val-Gly-NH₂ [XXX = nothing, Gly, β-Ala, γ-Abu, 6-Ahx; YYY = His, His(3-Bom), (S)-cyclopentylglycine (CPG); ZZZ = Phe, DPhe; DNal(2')], show unique selectivity and potency among the receptors tested. In particular, one of the ligands, Delt-38B--c[Gly-CPG-DNal(2')Arg-Trp-Glu]-Val-Val-Gly-NH₂, is a human melanocortin receptor (hMC1R) antagonist (IC₅₀ = 12 nM) the first potent hMC1R antagonist discovered. These results provide strong evidence supporting our hypothesis that ligand scaffolds for different G-protein coupled receptors (GPCRs) can be used to design ligands for other GPCRs. In addition, the structures of some of the ligands have been analyzed by high field solution NMR and their conformation evaluated by modeling with MacroModel. The conformations obtained from these methods help us better understand the structural basis the selectivities and ligand-receptor interactions.

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Islam, Mohammad Kaisarul. "Novel ligands targeting the DNA/RNA hybrid and telomeric quadruplex as potential anticancer agents." Thesis, King's College London (University of London), 2016. https://kclpure.kcl.ac.uk/portal/en/theses/novel-ligands-targeting-the-dnarna-hybrid-and-telomeric-quadruplex-as-potential-anticancer-agents(ce8f3d0e-317d-4c2e-b64a-e13e283f7b95).html.

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Telomeres are repetitive sequences of DNA at the ends of chromosomes that become progressively shorter during cell division, acting as a form of “biological clock” causing cell death once they have reached a certain length. Almost 90% of cancer cells overexpress the enzyme telomerase which can lengthen telomeres and confer immortality to the tumour cells. Thus, telomerase has become an important target for drug discovery in the oncology area, and there is also interest from researchers investigating the aging process. During the catalytic cycle of telomerase, a unique DNA/RNA hybrid duplex (DRH) forms that is typically between 6-11 base pairs long and is key to extending the telomere. There is interest in discovering small drug-like molecules that can recognize and bind to this hybrid duplex to inhibit selectively telomerase, either by stabilizing the structure and thereby preventing telomerase dissociation (a key step in the catalytic cycle) or by sufficiently distorting the hybrid duplex to cause the misalignment of key catalytic groups. This project began by using oligonucleotides representing DNA/RNA hybrid duplex (DRH), telomeric G-quadruplex and control duplex DNA sequences to screen against the National Cancer Institute compound libraries (i.e., Diversity Set II, Mechanistic Set and Natural Product Set) using a high throughput Fluorescent Resonance Energy Transfer (FRET)-based DNA thermal denaturation assay to determine binding affinity and specificity. Thirteen novel chemical scaffold families were identified in the assay, compounds which showed a >5 °C selective stabilization of the DNA/RNA hybrid duplex at a 1 μM ligand concentration. Chemical modifications were then made to these scaffolds to generate focused libraries of analogues to improve selectivity, potency and drug-likeness, and to provide Structure-Activity Relationship (SAR) information. A total of 49 novel molecules were synthesized and then screened against an expanded range of four different nucleic acid constructs including telomeric and DNA/RNA hybrid duplex sequences. A number of compounds showed selective DNA/RNA hybrid stabilization potential with some compounds also showing notable telomeric G-quadruplex stabilization without significant affinity for promoter G-quadruplexes (i.e., c-Kit1, c-Kit-2 and c-Myc) and control duplex DNA sequences. The compounds from library-1 provided DNA/RNA hybrid duplex stabilization in the 0.5-7.2 C range and telomeric G-quadruplex stabilization in the 0.2-6.5 C range at a 1 μM ligand concentration. Molecular modelling and molecular dynamics studies confirmed that the methylene spacer between the benzimidazole and phenylene moieties of molecules within library-1 is perfectly shaped to fit within the DRH sequence. In addition, it was confirmed that minor-groove binding and simultaneous intercalation between the nucleobases of a DNA/RNA hybrid duplex requires a linker of specific length (i.e., an eight methylene spacer as in compound 3.3). Selected compounds were then studied further using a variety of biological techniques to confirm selective telomerase inhibition and cell-based assays to utilize their potential as antitumour agents.

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Radal, Léa. "Synthèse, caractérisation et complexation aux métaux de transition de ligands hybrides ferrocénylphosphine di- et trifonctionnels." Thesis, Bourgogne Franche-Comté, 2020. http://www.theses.fr/2020UBFCK001.

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Les composés organométalliques qui contiennent un métal lié à au moins un atome de carbone, sont utilisés dans des domaines très variés de la chimie : par exemple en recherche médicale pour des traitements anticancéreux, dans les réactions catalytiques en tant que catalyseurs ou ligands, en électrochimie pour leur potentiel rédox, en chimie des matériaux pour leurs propriétés optiques ou électroniques. La famille de composés organométalliques centrale de cette thèse est celle du ferrocène pour ses propriétés physiques et chimiques, et en particulier sa robustesse, et la possibilité de multiples substitutions offerte sur ses deux cycles cyclopentadiényle en position « sandwich » autour du fer, la fonctionnalisation dissymétrique de ces anneaux cyclopentadiényle étant un défi majeur.La première partie de cette thèse analyse la bibliographie des synthèses de composés ferrocéniques hybrides phosphorés, et leurs études en tant que ligands en chimie de coordination et en catalyse.La deuxième partie porte sur le développement de deux nouvelles familles de ferrocènes hybrides [acide de Brönsted/base de Lewis] élaboré sur une plateforme ferrocénique préalablement dialkylée à conformation contrainte. La synthèse de ligands de type [PR2/CO2H] et leurs études de complexation ont été réalisées. L’évolution de cette famille par réaction d’amidation a permis d’accéder à de nouveaux ferrocènes plus polaires de type [PR2/CONHCH2SO3NHEt3].La troisième partie traite du développement de ferrocènes hybrides trifonctionnels de type [phosphine/aminoacide]. Différents aminoacides ont été intégrés qui permettent de diversifier les environnements stériques, pouvant ainsi rigidifier les structures de ligands et favoriser divers types de complexation avec des métaux de transition en vue de leur utilisation en catalyse sélective
Organometallic compounds with at least one metal-carbon bond are used in various fields of chemistry: for example, in medical research for anticancer treatments, in catalytic reactions as catalysts or ligands, in electrochemistry for their redox potentials, in materials chemistry for their optical and electronic properties. The principal family of organometallic compounds of this thesis is ferrocene due to its physical and chemical properties particularly its robustness and the possibility of multiple substitutions on cyclopentadienyl ligands, the dissymmetric functionalization of these cyclopentadienyl rings being a major challenge.The first part of this thesis describes the bibliography of syntheses of phosphorus-containing hybrid ferrocene compounds and their studies as ligands in coordination chemistry and catalysis.The second part focuses on the development of two new hybrid ferrocene families [Brönsted acid/Lewis base] on a dialkylated ferrocene platform with constrained conformation. More precisely, the synthesis and complexation of ligands type [PR2/CO2H] and [PR2/CONHCH2SO3NHEt3] have been done. Interestingly, the evolution of the former ligand type by amidation allows us to have an access to more polar ferrocene families (latter type).The third part investigates the development of trifunctional hybrid ferrocenes type [phosphine/aminoacid]. Various aminoacids have been introduced to diversify steric environments, lock the ligand structures and favor various modes of complexation with transition metals to use in selective catalysis

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17

Sans, Valls Marta. "The chiral cyclobutane motif in advanced materials and catalysis: organogelators, surfactants, hybrid silicas and metal ligands." Doctoral thesis, Universitat Autònoma de Barcelona, 2014. http://hdl.handle.net/10803/285648.

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Les diamines i els diàcids carboxílics en forma cíclica, ambdues estructures substituïdes en les posicions 1,2 de l’anell carbonat, constitueixen versàtils building blocks en química orgànica. Han estat utilitzats en la preparació de diferents derivats des de materials híbrids a lligands en reaccions catalítiques i en auto-ensamblatge de molècules (utilitzades com a plantilles per a nanoestructures inorgàniques), gràcies a la possibilitat de controlar la seva estereoquímica, rigidesa i requeriments estèrics. Així doncs, en la primera part d’aquesta Tesi Doctoral s’ha portat a terme la síntesi enantio- i diastereocontrolada dels quatre estereoisòmers de la ciclobutan-1,2-diamina amb ambdós grups amino protegits ortogonalment. Aquesta protecció assegura una funcionalització regioselectiva dels dos grups amino i en reté la quiralitat en el cas dels estereoisòmers cis que d’altra banda esdevindrien formes meso. La versatilitat d’alguns d’aquests compostos s’ha utilitzat en la preparació dels següents compostos o derivats. Hem de mencionar els organogeladors de baix pes molecular, els quals han mostrat habilitat de gelar toluè entre altres solvents. Aquests organogeladors estan constituïts per estructures ciclobutàniques i han estat comparats amb els organogels formats pels seus anàlegs amb anell ciclohexà. El seu comportament ha estat estudiat mitjançant l’ús de tècniques microscòpiques i per experiments de RMN a temperatura variable per tal de seguir el procés de gelació, mostrant una important dependència en l’estereoquímica cis/trans i tambè una important dependència de la mida de l’anell (ciclohexà vs ciclobutà). En segon lloc, la síntesi estereoselectiva de nous tensioactius de tipus bola derivats de la ciclobutan-1,2-diamina i el ciclobutan-1,2-dicarboxílic àcid s’ha portat a terme. La seva caracterització físico-química i les seves propietats d’agregació han estat descrites. S’ha posat èmfasis en l’estudi de l’efecte de la seva estereoquímica relativa i l’àtom connector a l’anell ciclobutà. En tercer lloc, en la present Tesi doctoral s’han sintetitzat síliques híbrides derivades de la ciclobutan-1,2-diamina utilitzant diferents mètodes de condensació. La seva morfologia ha estat estudiada per RMN en estat sòlid i per SEM. Finalment, s’ha utilitzat la funcionalitat ciclobutan-1,2-diamina com a precursor per preparar una sílica capaç de coordinar rodi per tal de sintetitzar un material quiral per catàlisi. D’altra banda, diferents pirrolidines contenint el ciclobutà disubstituit en posicions 1,3 com a element quiral han estat també sintetitzades a partir de la (-)-verbenona com a material de partida. Aquests compostos han estat eficientment utilitzats com a estabilitzants en la preparació de nanopartícules de ruteni. Finalment, aquestes nanopartícules han estat provades com a catalitzadors en reaccions de reducció mostrant una bona selectivitat i activitat catalítica.
Cyclic 1,2-diamines and 1,2-dicarboxylic acids are versatile building blocks in organic chemistry. They have been used as scaffolds for the preparation of various derivatives ranging from hybrid materials to ligands in catalyzed reactions and self-assembling molecules (used as templates for inorganic nanostructures), thanks to the possibility to control their stereochemistry, steric demand and rigidity. Thus, in the first part of this PhD Thesis, an efficient enantio and diastereocontrolled synthesis of the four stereoisomers of cyclobutane-1,2-diamine derivatives has been achieved. Their orthogonal protection secures the regioselective functionalization of both amino groups retaining the chirality in the case of cis-compounds that otherwise would become meso forms. Then, the versatility of some of these scaffolds has been used in the preparation of the following compounds or materials. We must mention low molecular weight gelators (LMWGs), which have shown the ability to gelate toluene among other solvents. These organogelators are based on cyclobutane structures and have been compared with the ones formed by the cyclohexane analogues. Their behaviour and morphology have been studied by microscopy and by NMR experiments at variable temperature in order to monitor the gelation process, showing high dependence on their cis/trans stereochemistry and also an important dependence on their ring size (cyclohexane vs cyclobutane). Secondly, the stereoselective synthesis of new chiral bola surfactants derived from cyclobutane-1,2-diamine and cyclobutane-1,2-dicarboxylic acid has been achieved and their physicochemical characterization and their aggregation properties have been described. Special attention has been focused on the study of the effect of their relative stereochemistry and the connecting atom in the cyclobutane ring. Moreover, the synthesis of hybrid silicas derived from cyclobutane-1,2-diamine using different condensation methods has also been achieved in this Thesis. Their morphology has been studied by NMR in solid state and by SEM. Furthermore, cyclobutane-1,2-diamine have been also used as precursor to prepare a silica able to coordinate rhodium in order to prepare a chiral material for catalysis. On the other hand, pyrrolidines containing the 1,3-disubsituted cyclobutane as a chiral moiety have been also prepared from (-)-verbenone as a starting material. These compounds have been efficiently used as stabilizers in the preparation of ruthenium nanoparticles. Finally, these nanoparticles have been tested as catalysts in reduction reactions showing good catalytic activity and selectivity.

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Dwadnia, Nejib. "Ligands ferrocéniqes hybrides (P, N) : synthèse, coordination aux métaux et applications en catalyse de couplage d'arylation." Thesis, Bourgogne Franche-Comté, 2017. http://www.theses.fr/2017UBFCK050/document.

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La thématique de recherche développée au cours de cette thèse concerne l’élaboration de nouveaux ligands mixtes ferrocéniques hybrides-(P,N) à conformation contrôlée, robustes et stables à l’air. Ces ligands tétradentes hybrides comportent deux types de fonctions coordinnantes aux propriétés stériques et électroniques distinctes. Leur chimie de coordination avec des métaux tels que l’or ou le palladium a été étudiée et certains complexes d’Au(I) isolés ont été utilisés en catalyse de couplage d’arylation des iodures d’aryles. La première partie de cette thèse porte sur une étude bibliographique concise reflétant la diversité des ligands ferrocénique azotés et hybride-(P,N) et leurs voies de synthèse, pour finalement retracer leur chimie de coordination aux métaux de transition (Pd, Au) ainsi que leurs applications catalytiques. La deuxième partie traite la synthèse d’une famille de composés bis(aminométhyl)-ferrocène et les dérivés associés de manière sélective par amination réductrice du 1,1'- diformylferrocène ou du 1,1'-bis(tert-butyl)-3,3'-diformylferrocène avec une variété d’amines primaires et secondaires. Dans la troisième partie nous présentons les stratégies de synthèse qui ont été utilisées pour la préparation de hybrides-(P,N) ferrocéniques ainsi que leur contrôle conformationnel, et la caractérisation structurale de ces molécules. Leur coordination à des sels de palladium a été étudiée. Les complexes de coordinations correspondants ont étés isolés avec de très bons rendements, et caractérisés en solution par RMN 1H , 13C, 31P, 15N, et à l’état solide par diffraction des rayons X. La quatrième et dernière partie est dédiée à l’étude de la coordination à l’or. Trois nouveaux complexes d’Au(I) dinucléaires, incorporant des ligands ferrocéniques hybride-(P,N), ont étés isolés est caractérisés. L‘un parmi ces complexes a montré une efficacité particulière pour la réaction d’arylation des iodures d’aryles
The research theme developed during this thesis concerns the development of new hybrid ferrocene hybrid (P, N) ligands with controlled conformation, robust and stable to air. These hybrid tetradent ligands comprise two types of coordinating functions with distinct steric and electronic properties. Their coordination chemistry with metals such as gold or palladium has been studied and some isolated Au (I) complexes have been used in the arylation coupling catalysis of aryl iodides

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Vuong, Khuong Quoc Chemistry Faculty of Science UNSW. "Metal complex catalysed C-X (X = S, O and N) bond formation." Awarded by:University of New South Wales. Chemistry, 2006. http://handle.unsw.edu.au/1959.4/23015.

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This thesis describes the catalysed addition of X-H bonds (X = S, O and N) to alkynes using a range of novel rhodium(I) and iridium(I) complexes containing hybrid bidentate phosphine-pyrazolyl, phosphine-imidazolyl and phosphine-N heterocyclic carbene (NHC) donor ligands. The synthesis of novel bidentate phosphine-pyrazolyl, phosphine-imidazolyl (P-N) and phosphine-NHC (PC) donor ligands and their cationic and neutral rhodium(I) and iridium(I) complexes [M(P N)(COD)]BPh4, [M(PC)(COD)]BPh4, [Ir(P-N)(CO)2]BPh4 and [M(P-N)(CO)Cl] were successfully performed. An unusual five coordinate iridium complex with phosphine-NHC ligands [Ir(PC)(COD)(CO)]BPh4 was also obtained. Seventeen single crystal X-ray structures of these new complexes were determined. A range of these novel rhodium and iridium complexes were effective as catalysts for the addition of thiophenol to a variety of alkynes. Iridium complexes were more effective than rhodium analogues. Cationic complexes were more effective than neutral complexes. Complexes with hybrid phosphine-nitrogen donor were more effective than complexes containing bidentate nitrogen donor ligands. An atom-economical, efficient method for the synthesis of cyclic acetals and bicyclic O,O-acetals was successfully developed based on the catalysed hydroalkoxylation. Readily prepared terminal and non-terminal alkyne diols were cyclised into bicyclic O,O-acetals in quantitative conversions in most cases. The efficiency of a range of rhodium and iridium complexes containing bidentate P-N and PC donor ligands as catalysts for the cyclisation of 4-pentyn-1-amine to 2-methyl-1-pyrroline varied significantly. The cationic iridium complexes with the bidentate phosphine-pyrazolyl ligands, [Ir(R2PyP)(COD)]BPh4 (2.39-2.42) were extremely efficient as catalysts for this transformation. Increasing the size of the substituent on or adjacent to the donor led to improvement in catalytic activity of the corresponding metal complexes. The mechanism of the catalysed hydroalkoxylation was proposed to proceed by the initial activation of the alkyne via ?? coordination to the metal centre. The ?? binding of both aliphatic and aromatic alkynes to [Ir(PyP)(CO)2]BPh4 (2.44) was observed by low temperature NMR and no reaction between 2.44 and alcohols was observed. In contrast, the facility in which thiol and amine oxidatively added to 2.44 led the proposal that in the hydrothiolation and hydroamination reaction, the catalytic cycle commences with the activation of the X-H bond (X = S, N) by an oxidative addition process.

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Niaz, Basit [Verfasser]. "Synthesis of Novel Biaryl-Type P=C-N-Heterocyclic σ2P,N- and σ2P,σ3P-Hybrid Ligands / Basit Niaz." Greifswald : Universitätsbibliothek Greifswald, 2012. http://d-nb.info/1021299014/34.

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21

Woiterski, André. "Density functional and hybrid QM-MM calculations of Cu13-clusters with alkylthiolate ligands and their two-dimensional periodic arrangements." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=96891845X.

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Thangavelu, Sonia G. "Structural Variations and Luminescence of UO22+ Hybrid Materials Containing N-donor Chelating Ligands and/or O-donor Assembly Linkers." Thesis, The George Washington University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3717926.

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This dissertation is based on the hydro(solvo)thermal syntheses and characterization of uranyl (UO₂²⁺) coordination polymers (CPs) via single-crystal X-ray diffraction (SC-XRD), powder X-ray diffraction (PXRD), and luminescence spectroscopy. The rich structural portfolio of uranyl CPs arises from the UO₂²⁺ cation’s tendency to undergo hydrolysis, and form uranyl oligomeric species (or secondary building units, SBUs). Because of hydrolysis, synthetic control of SBUs is difficult and more often then not, their solid-state crystallization is random and unpredictable. Thus, it is challenging to know what building unit will be observed in a uranyl CP.

Our strategy to address such challenges and potentially thwart hydrolysis is to use N-donor chelating ligands. These ligands offer potential chelating sites that may allow for direct coordination to UO₂²⁺ and thus essentially promote specific uranyl building units. The N-donor ligands chosen in our study are 2,2’:6,2”-terpyridine (TPY), analogs of 2,2’-bipyridine (BPY), 2,4,6-tripyridyl-s-triazine (TPTZ), and 2,3,5,6-tetrakis(2-pyridyl)pyrazine (TPPZ). By restricting UO₂²⁺ speciation, assembly of aromatic or aliphatic O-donor linkers to available coordination sites on UO₂²⁺ allowed us to synthesize a series of uranyl CPs containing N-donor (TPY, TPTZ, BPY analogs) and O-donor co-ligands. These coordination polymers resulted in extended structures with unique structural topologies and luminescent features.

Depending on the choice of N- and O-donors, structural variations in the local UO₂²⁺ coordination sphere and global structure within a uranyl CP were observed. N-donor chelating ligands were also explored as guest molecules, in which a series of CPs containing TPTZ, BPY analogs, or TPPZ and different O-donor aliphatic or aromatic linkers were synthesized. These guests were found to stabilize the structure through non-covalent interactions or participate as charge balancing species. Beyond structural manipulation of our materials, we also studied UO₂²⁺ luminescence and lifetimes within our uranyl CPs. We observe that modifications on either the N- or O-donor (i.e. sterics, functional groups, and/or non-covalent interactions) or a change in the local and global structure of a CP influences UO₂²⁺ luminescence thus resulting in unique spectral signatures.

Given the influence of N-donors and O-donors on the structure and luminescence of an uranyl CP, we also explored the synthesis of uranyl complexes using N-donor BPY, 5,5’-dimethyl-2,2’-bipyridine (MeBPY), and TPY ligands exclusively via self assembly conditions in the presence of sunlight and ambient light. Unexpectedly, we observe the presence of peroxo ligands in our crystal structures. To explore the origin of the peroxo ligand, rigorous synthetic experiments were performed in which the presence of peroxo most likely arises from a mechanism consistent to photo-excitation of UO₂²⁺.

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Rampazzi, Vincent. "Chimie de coordination du phosphore aux métaux du groupe 11 : progrès en catalyse de couplage C-N au Cu(I) et nouveaux complexes polyphosphines de l'Au(I)." Thesis, Dijon, 2014. http://www.theses.fr/2014DIJOS025/document.

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De nos jours et depuis quelques années maintenant, le principe de développement durable encourage les chimistes de tous horizons à développer de nouvelles méthodes de synthèse économiques et écologiques, les ressources naturelles de notre planète ne sont pas illimitées. Parmi les ressources les plus exploitées, nous trouvons le pétrole et le gaz. Outre ces derniers et le gaz, les métaux précieux sont également devenus indispensables.Cette thèse se concentre sur la valorisation de complexes de cuivre et d’or, obtenus à partir de ligands phosphorés synthétisés au sein du laboratoire. Dans un premier temps, nous verrons la mise au point d’une réaction de N-arylation de pyrazoles catalysée par un complexe de cuivre portant un ligand hybride phosphinoalcène. Dans un deuxième temps, les propriétés de coordination de l’or à différentes polyphosphines ferrocéniques seront étudiées. Plusieurs complexes innovants seront mis en évidence et pourront être utilisés dans le cadre de futures études de catalyse, ou de luminescence
Nowadays, sustainable development encourages chemists to develop new economic and ecologic synthesis, because natural ressources are reducing. Most exploited ressources are gas and petroleum, but precious metals are also essential. This thesis is focusing on the enhancement of gold and copper complexes, obtained in our laboratory from phosphorous-based ligands. In the first part, we will develop a new system for the N-arylation of pyrazoles from a copper complexe coordinated by a new hybrid phosphinoalkene ligand. In the second part, coordination properties of gold to different ferrocenic polyphosphine will be studied. Several new innovative complexes will be isolated, and could be used in future catalytic or luminescent studies

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Dolles, Dominik [Verfasser], Michael [Gutachter] Decker, and Christoph [Gutachter] Sotriffer. "Development of Hybrid GPCR Ligands: Photochromic and Butyrylcholinesterase Inhibiting Human Cannabinoid Receptor 2 Agonists / Dominik Dolles ; Gutachter: Michael Decker, Christoph Sotriffer." Würzburg : Universität Würzburg, 2018. http://d-nb.info/1162062444/34.

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Allouch, Fatima. "Synthèse et applications de nouveaux complexes métallocéniques multidentes." Thesis, Dijon, 2013. http://www.theses.fr/2013DIJOS002.

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Ce mémoire porte sur l’accès simple et peu coûteux à de nouveaux ligands ferrocéniques aminés et aminophosphinés et leur coordination avec des métaux de transition pour des applications en catalyse homogène.Des métallo-ligands aminés flexibles ont été obtenus et caractérisés après amination réductrice du 1,1’-diformylferrocène. D’autres ligands (N,N) rigides ont été isolés au départ du précurseur du 1,1’-di-tert-butyl-3,3’-diformylferrocène. Des aza-ferrocénophanes ont également été facilement préparés avec ces deux précurseurs carbonylés. Lors de la coordination de ces ligands avec le palladium, un palladacycle original a été isolé et caractérisé par diffraction de rayons X.Des ligands ferrocéniques (N,P) ont été obtenus par trois méthodes: i) ortholithiation de ligands ferrocéniques aminés suivie d’un ajout de chlorophosphine, ii) amination réductrice des ferrocènes formylés substitués ou non en présence d’amine portant une fonction phosphine, iii) substitution directe du ferrocène dilithié par des chlorophosphines comportant un hétérocycle azoté. Leur coordination avec du palladium et du platine a été étudiée. Ces métallo-ligands hybrides ont été impliqués dans des réactions de chlorures d’aryle avec des acides arylboroniques (couplage de Suzuki), ainsi que dans la réaction de Sonogashira avec le couplage de bromures et de chlorures d’aryle avec le phénylacétylène
This thesis focuses on simple and inexpensive access to new amino and aminophosphine ferrocenyl ligands and their coordination with transition metals for applications in homogeneous catalysis.Flexible amine metallo-ligands were obtained and characterized after reductive amination of 1,1'-diformylferrocene. Other rigid (N,N) ligands were isolated starting from the precursor 1,1'-di-tert-butyl-3, 3'-diformylferrocene. Aza-ferrocenophanes were also easily prepared with these two formyl precursors. During the coordination of these ligands with palladium, a stable and original palladacycle was isolated and characterized by DRX.(N,P) ferrocenyl ligands were obtained by three methods: i) ortholithiation of aminoferrocenyl ligands followed by addition of chlorophosphines, ii) reductive amination of substituted or not formylferrocene in the presence of amine bearing a phosphine function, iii) direct substitution of dilithiated ferrocene by chlorophosphines with a nitrogen-containing heterocycle. Their coordination with palladium and platinum has been studied. These hybrid metallo-ligands have been implicated in the reactions of aryl chlorides to arylboronic acids (Suzuki cross-coupling), as well as in the Sonogashira reaction involving of coupling aryl bromides and chlorides to phenylacetylene

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Lefrançois, Aurélie. "Synthèse de nanocristaux de type Chalcopyrite en vue d'applications en cellules solaires." Phd thesis, Université de Grenoble, 2013. http://tel.archives-ouvertes.fr/tel-01062176.

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Cette thèse porte sur l'étude de nanocristaux semi-conducteurs ternaires, et leur application dansdes cellules solaires hybrides organiques/inorganiques. Les nanocristaux semi-conducteurs absorbentla lumière à des longueurs d'ondes déterminées par leur taille et leur composition, et conduisent lescharges électriques. Ils sont stables en solution, ce qui permet un dépôt de couches minces à bascout. Aujourd'hui les meilleurs rendements en cellules solaires hybrides sont obtenus à partir de nanocristauxbinaires contenant soit du plomb, soit du cadmium. Les nanocristaux ternaires conserventles propriétés particulières des nanocristaux binaires tout en permettant de s'affranchir des élémentstoxiques. Cependant, leur synthèse reste à optimiser pour contrôler de leur structure cristalline et leurcomposition.Nous avons réalisé, par voie chimique, la synthèse de nanocristaux de CuInS2 de taille et de compositioncontrôlées. En suivant in situ la synthèse de ces nanocristaux par diffraction des rayons X sous rayonnementsynchrotron nous avons trouvé que les précurseurs s'organisent avant nucléation sous forme deplans espacés par deux longueurs du ligand utilisé (ici dodécanethiol, DDT). Cela impacte nucléationet croissance des nanocristaux. Les ligands stabilisent les nanocristaux en solution colloïdale, maisleur caractère isolant peut inhiber le transfert et le transport de charges. Le remplacement du ligandd'origine (DDT) par un ligand plus court, l'éthylhexanethiol (EHT), modifie les niveaux d'énergie etpermet d'augmenter la conductivité des films de nanocristaux. Nous avons intégré des nanocristauxde CuInS2 entourés d'EHT dans des cellules hybrides constituées d'un polymère conjugué (P3HT) etd'un fullerène (PCBM). L'efficacité des cellules solaires contenant des nanocristaux entourés d'EHTest significativement améliorée par rapport à celle des cellules de P3HT :PCBM réalisées dans lesmêmes conditions. Le transfert et la mobilité des charges sont étudiés par RPE sous éclairement etphoto-CELIV respectivement. De ces études il ressort que l'amélioration des cellules provient d'unemeilleure génération et dissociation des charges.

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Hodgson, Richard. "Novel chiral di-N-heterocyclic carbene and hybrid phosphine-N-heterocyclic carbene ligands and their application to transition metal mediated asymmetric catalysis." Thesis, University of York, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423839.

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Köhler, Christian [Verfasser]. "Spin crossover behavior of 1,3,4-oxadiazole based dinuclear iron(II) complexes und functionalized phosphonates as bridging ligands in inorganic-organic hybrid-materials / Christian Köhler." Mainz : Universitätsbibliothek Mainz, 2016. http://d-nb.info/1105589935/34.

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Baffert, Mathieu. "Synthesis of ruthenium complexes having one or more N-heterocyclic carbene ligands supported on hybrid mesostructured silicas and their use in the hydrogenation of carbon dioxide." Phd thesis, Université Claude Bernard - Lyon I, 2011. http://tel.archives-ouvertes.fr/tel-00838661.

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The goal of this PhD was to elaborate supported Ru-NHC catalytic materials based on hybrid organic-inorganic materials having imidazolium units perfectly distributed within a silica matrix. Passivation of these imidazolium materials followed by formation of NHC-carbene and reaction with [RuCl2(p-cymene)]2 provided these well-defined surface sites of general structures RuCl2(NHC)(L), where L was para-cymene (p-cymene) or THF depending on the reaction conditions, which could be further replaced by PMe3. These systems were then tested in the hydrogenation of CO2 in presence of amine to give formamides. The mono-NHC systems were highly active only in the presence of PMe3 ligands, but suffered from Ru leaching, evidencing the low stability of the NHC-Ru bond under the reaction conditions. On the other hand, dinuclear bis-NHC Ru systems were also developed, and they displayed much improved activity and stability in the hydrogenation of CO2 in the presence of PMe3 compared to the mono-NHC systems. This allowed the use of much higher reaction temperatures (200 °C) and provided heterogeneous catalysts with performances close to those obtained with the best homogeneous catalysts, Cl2Ru(dppe)2.

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Weiß, Daniel Traugott [Verfasser], Fritz E. [Akademischer Betreuer] Kühn, and Richard W. [Akademischer Betreuer] Fischer. "Influence of Open Chain, Tetradentate NHC and NHC/Pyridine Hybrid Ligands on the Coordination and Electrochemistry of Late Transition Metal Complexes / Daniel Traugott Weiß. Betreuer: Fritz E. Kühn. Gutachter: Fritz E. Kühn ; Richard W. Fischer." München : Universitätsbibliothek der TU München, 2015. http://d-nb.info/1079974563/34.

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Karpati, Szilvia. "Development of a multimodal nanoprobe for the comprehension of post-stroke inflammation." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1211.

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L’accident vasculaire cérébrale (AVC) ischémique est une des premières causes de mortalité dans le monde, par conséquent il constitue un véritable enjeu de santé publique. Cette pathologie résulte de l’obstruction d’une artère cérébrale par un caillot et déclenche une inflammation, pouvant majorer les lésions tissulaires du cerveau. À ce jour les traitements anti-inflammatoires appliqués en clinique se sont révélés inefficaces. Il est donc indispensable de développer de nouvelles approches diagnostiques pour une meilleure compréhension des mécanismes biologiques impliqués dans cette pathologie. Dans ce contexte, nous avons proposé la conception d’une nanoplateforme hybride multimodale comme agent de contraste adapté à trois techniques d’imagerie médicale. Ces nanoparticules au cœur inorganique, composé de GdF3 augmentent sensiblement le contraste en IRM et leur opacité procure un rehaussement de contraste pour le Scanner Spectral à Comptage Photonique (SPCCT), une technique de développement récent. La troisième modalité, la microscopie biphotonique procure une haute résolution et une très grande sensibilité, tout en permettant d’obtenir des images en temps réel. Grâce à un chromophore adapté, greffé à la surface de la particule, cette modalité devient également accessible. Ces particules inorganiques sont synthétisées par une méthode solvothermale originale, développée par notre équipe. La surface des nanoparticules est ensuite modifiée par différents ligands polyéthylène glycol (PEG) fonctionnalisés, qui rendent les particules de GdF3 stables en milieu physiologique (comme le sang), biocompatibles et furtives. Enfin, un chromophore spécialement développé au sein de notre laboratoire, pour des applications d’absorption biphotonique, a été greffé à la surface de la particule. Le couplage du chromophore a été effectué via une réaction click azoture-alcyne, activée thermiquement (sans catalyse par Cu(I)). La toxicité des particules a été évaluée par deux techniques différentes, appliquées sur des cellules d’origine humaine. À l’issue de ces tests aucun effet cytotoxique n’a été observé. Après avoir démontré les propriétés multimodales de ces nanoobjets, des expériences précliniques in vivo ont été menées. Nous avons montré, que lors de l’observation du cerveau de souris la nanosonde augmente efficacement le contraste en SPCCT, IRM et produit un signal intense en microscopie 2-photons intravitale. Les particules se sont révélées particulièrement stables dans le sang : grâce à leur furtivité elles restent dans la circulation longtemps, ce qui favorise leur passage à travers la barrière hémato-enchéphalique lésée. Elles sont également phagocytées par les cellules immunitaires activées. La dynamique spatio-temporelle de ces cellules marquées par les nanoparticules a pu être imagée
Ischemic stroke, as one of the most common causes of death, represents an important health issue. The pathology consists of the occlusion of an artery in the brain leading to an acute inflammatory process. Post-stroke inflammation usually results in irreversible secondary brain tissue damage. To date, the clinical application of anti-inflammatory treatments has been either negative or inconclusive. For a better understanding of this complex physiological process and development of efficient treatment, there is an urgent need to develop performant in-vivo diagnostic tools. In that context, we proposed to design a multimodal hybrid nanoprobe for enhancing the contrast in three different clinical and pre-clinical imaging modalities. The ability of this probe to enhance contrast in MRI (Magnetic Resonance Imaging) and a recently developed spectral photon counting scanner computed tomography (SPCCT) is intrinsic to the inorganic GdF3 core. The inorganic nanoparticle size and morphology was optimized for the biological application. The third modality, two-photon imaging, provides high spatial resolution, high sensitivity, and allows real-time imaging. To make GdF3 nanoparticles visible by two-photon microscopy, a specially designed organic moiety is added to the nanoplatform. The inorganic nanoparticles are synthesized by the original solvothermal method developed in our group. Surface modifications with different PEG derivatives confer to the GdF3 nanoparticles high stability in physiological media (such as blood), biocompatibility, and stealth. The two-photon active chromophore synthesized in our laboratory is grafted to the particle surface via a thermally activated (catalyst-free) alkyne-azide click reaction. Toxicity of the nanoobjects has been assessed by using two different tests on four human-derived cells, and no cytotoxic effect of the particles was found. After the demonstration of the multimodality of the particles, pre-clinical in vivo experiments were performed. We evidenced that the particles successfully enhance SPCCT, MRI contrast in the brain of the small animal via a T2-effect and provide a high-intensity two-photon signal for in-vivo microscopy. Besides, the nanoparticles revealed to be stable and long-circulating in the blood, which favored their cross through the altered blood-brain barrier. Their phagocytose by activated immune cells offered the possibility to follow cell-trafficking

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Mougeot, Romain. "Synthèse de sondes fluorescentes hybrides epicocconone-triphénylamine pour le piégeage de protéines liées aux zones à risques de l'ADN." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMR126.

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La compréhension des mécanismes biologiques et l’implication des protéines dans ces mécanismes ont toujours été un enjeu important pour les biologistes. Les zones à risques de l’ADN impliquées dans les cancers, comme les G-quadruplex, les zones riches en Adénine-Thymine et leurs environnements proches sont particulièrement étudiés depuis de nombreuses années. L’essor des techniques d’analyses par fluorescence a permis aux scientifiques de mettre au point des sondes marquant ces domaines avec toujours plus de précision et de sensibilité. Cependant, de nombreuses interrogations existent sur la nature des interactions entre ces zones de l’ADN et les protéines. Afin de répondre à cette problématique, la synthèse d’une sonde pro-fluorescente alliant un ligand de l’ADN (conçu d’après les travaux des équipes de l’Institut Curie, UMR 176) à un piège à protéines (basé sur le squelette de l’epicocconone) a été réalisée et son efficacité biologique a été évaluée. Ces deux parties ont été assemblées en utilisant une réaction de cycloaddition 1,3 dipolaire spontanée entre un azoture et un alcyne contraint (SPAAC). De plus, au cours de ces travaux, une nouvelle bibliothèque de ligands de l’ADN a été synthétisée en utilisant une méthodologie innovante basée sur une réaction de C-H activation « on water »
Understanding biological process and proteins involved in has challenged biologists’ mind for a while. Specific DNA sequences, such as G-quadruplex and Adenine-Thymine rich sequences, have been studied for many years, especially for their involvement in genetic diseases like cancer. Scientists have also been interested in fluorescence monitoring and imaging of these specific sequences for a long time. Indeed, the huge sensitivity of these fluorescent technics and the wide scope of synthetic dyes available allowed several improvements on targeting DNA sequences responsible for genetic disorders. Nonetheless, relation between proteins and these areas remains mostly unknown. In order to answer this question, a pro-fluorescent dye built of two main parts, which are a DNA ligand (designed by Curie Institute teams, UMR 176) and a protein trap (based on epicocconone core). These parts were synthesized, coupled thanks to a Spontaneous Azoture Alkyne Cycloaddition (SPAAC) and the biological properties of the probe were evaluated. Furthermore, new ligands were synthesized using a new and innovating method of “on water” C-H activation reaction

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Malicorne, Sébastien. "Recherche d’interactants du domaine immunosuppresseur des protéines d’enveloppe rétrovirales." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS579.

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La plupart des virus ont développé des mécanismes de résistance ou de suppression du système immunitaire pour parvenir à infecter durablement leur hôte. Ces mécanismes demeurent encore imparfaitement connus. Un domaine immunosuppresseur (IS) a été identifié au niveau de la région transmembranaire des protéines d’enveloppe des rétrovirus endogènes ou infectieux. Ce domaine hautement conservé a été décrit par exemple comme inhibant l’activation lymphocytaire. Dans le laboratoire, il a été caractérisé en particulier via des expériences de rejet de cellules tumorales in vivo, ce qui a permis de définir des mutations inactivatrices. Afin de mieux comprendre les mécanismes de résistance des rétrovirus au système immunitaire, mes travaux de thèse ont porté sur l’identification de la ou des protéines capables d’interagir avec le domaine IS. Plusieurs approches cellulaires et moléculaires ont été développées, basées pour la plupart sur l’utilisation de sondes fluorescentes obtenues par synthèse chimique, constituées des domaines IS provenant de différents rétrovirus. Dans un premier temps, les cellules du système immunitaire qui lient les protéines virales ont été identifiées : les lymphocytes B et les cellules myéloïdes (monocytes, cellules dendritiques et macrophages). Dans un second temps, des expériences de co-immunoprécipitation et de chromatographie d’affinité couplées à la spectrométrie de masse ont été réalisées dans le but d’identifier sur ces cellules les protéines membranaires responsables de ces liaisons. Plusieurs agents de couplages chimiques ont été utilisés afin de maintenir les liaisons domaine IS - protéine de faibles affinités. En raison de résultats non-reproductibles obtenus au cours de ces expériences, des tests de liaison du domaine IS sur des cellules transfectées avec des banques d’ADNc, ou lors d’expériences de double hybride ont été réalisées. Ces deux approches ont permis d’identifier des protéines membranaires potentiellement impliquées dans la liaison du domaine IS : les protéines X1 et X2. Les co-transfections de vecteurs d’expression du domaine IS et de X2 ont mis en évidence des interactions protéiques au cours d’expériences de co-immunoprécipitation et de microscopie confocale, en particulier avec le domaine IS du rétrovirus HIV-1. Concernant X1, sa transfection induit la liaison cellulaire des domaines IS de HERV-W et MLV. En revanche, aucune interaction directe entre X1 et le domaine IS n’a pu être démontrée, notamment dans des expériences de co-immunoprécipitation et de microscopie confocale.La découverte des protéines membranaires qui interagissent avec le domaine IS demeure un enjeu critique pour la compréhension des voies de signalisation et de transcription qui permettent aux rétrovirus d’exercer leur effet sur le système immunitaire, l’objectif de ces travaux étant d’identifier à terme des nouvelles cibles thérapeutiques.En conclusion, même si des travaux complémentaires demeurent nécessaires, les protéines X1 et X2 pourraient contribuer à l’immunosuppression rétrovirale
Most viruses have developed mechanisms of resistance or suppression of the immune system to achieve lasting infection of their host. These mechanisms are still imperfectly known. An immunosuppressive (IS) domain has been identified in the transmembrane region of envelope proteins of endogenous or infectious retroviruses. This highly conserved domain has been described, for example, as inhibiting lymphocyte activation. In the laboratory, it has been characterized by tumor cell rejection experiments in vivo, which has made it possible to define inactivating mutations. In order to better understand the mechanisms of resistance of retroviruses to the immune system, my thesis focused on the identification of the protein(s) interacting with the IS domain. Several cellular and molecular approaches have been developed, based for the most part on the use of fluorescent probes obtained by chemical synthesis, consisting of IS domains from different retroviruses. At first, immune system cells that bind viral proteins have been identified: B cells and myeloid cells (monocytes, dendritic cells and macrophages). In a second step, co-immunoprecipitation and affinity chromatography coupled to mass spectrometry were performed to identify on these cells the membrane proteins responsible for these bonds. Several chemical coupling agents have been used to prevent detachment of low affinity binding between proteins and the IS domain. Due to non-reproducible results obtained during these experiments, IS domain binding assays on cells transfected with cDNA libraries, or in double hybrid experiments were performed. These two approaches made it possible to identify membrane proteins potentially involved in the binding of the IS domain: the X1 and X2 proteins. Co-transfections of IS domain and X2 expression vectors demonstrated protein interactions in co-immunoprecipitation and confocal microscopy experiments, particularly with the IS domain of the HIV-1 retrovirus. Concerning X1, its transfection induces binding of the IS domains of HERV-W and MLV on cells membrane. On the other hand, no direct interaction between X1 and the IS domain could be demonstrated, especially in co-immunoprecipitation and confocal microscopy experiments.The discovery of membrane proteins that interact with the IS domain remains a critical issue for understanding the signaling and transcription pathways that allow retroviruses to exert their effect on the immune system, the aim of this work being to identify new therapeutic targets.In conclusion, although further work is still needed, the X1 and X2 proteins may contribute to retroviral immunosuppression

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Amarante, Tatiana Ribau. "New oxomolybdenum(VI) hybrid materials." Doctoral thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/12298.

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Doutoramento em Química
In this thesis, 2,2’-bipyridine (bipy), di-tert-butyl-2,2’-bipyridine (di-t-Bubipy), 2,2’-bipyridine-5,5’-dicarboxylic acid (H2bpdc), 2-[3(5)-pyrazolyl]pyridine (pzpy) and 2-(1-pentyl-3-pyrazolyl)pyridine (pent-pp) ligands were used as the N,N-chelate ligands in the formation of discrete [MoO2Cl2L]-type complexes. These complexes were employed as precursors for the preparation in aqueous media of oxomolybdenum(VI) products with a wide range of structural diversity. Three distinct heating methods were studied: hydrothermal, reflux or microwave-assisted synthesis. An alternative reaction with the inorganic molybdenum(VI) trioxide (MoO3) and the ligands di-t-Bu-bipy, H2bpdc and pzpy was also investigated under hydrothermal conditions. The distinct nature of the N,N-chelate ligands and/or the heating method employed promoted the isolation of a series of new oxomolybdenum(VI) hybrid materials that clearly reflected the strong structure-directing influence of these ligands. Thus, this thesis describes the synthesis and characterization of the discrete mononuclear [MoO2Cl2(pent-pp)], the dinuclear [Mo2O6(di-t-Bu-bipy)2] and the octanuclear [Mo8O22(OH)4(di-t-Bu-bipy)4] complexes as well as the highly unique polymeric materials {[MoO3(bipy)][MoO3(H2O)]}n, (DMA)[MoO3(Hbpdc)]·nH2O, [Mo3O9(pzpy)]n and [Mo2O6(pent-pp)]n (fine structural details of compound [Mo2O6(pent-pp)]n are presently unknown; however, characterization data strongly pointed toward a polymeric oxide hybrid compound). The catalytic behaviour of the discrete complexes and the polymeric compounds was tested in olefin epoxidation reactions. Compounds [Mo3O9(pzpy)]n and [Mo2O6(pent-pp)]n acted as sources of soluble active species that where identified as the oxodiperoxido complexes [MoO(O2)2(pzpy)] and [MoO(O2)2(pent-pp)], respectively. The majority of the compounds here presented were fully characterized by using solid-state techniques, namely elemental analyses, thermogravimetry, FT-IR, solid-state NMR, electron microscopy and powder X-ray diffraction (both from laboratory and/or synchrotron sources).
Nesta tese as moléculas 2,2’-bipiridina (bipy), di-tert-butil-2,2’-bipiridina (di-t-Bu-bipy), ácido 2,2’-bipiridina-5,5’-dicarboxílico (H2bpdc), 2-[3(5)-pirazolil]piridina (pzpy) e 2-(1-pentil-3-pirazolil)piridina (pent-pp) foram utilizadas como ligandos bidentados de azoto para a formação de complexos do tipo [MoO2Cl2L], no intuito de investigar a diversidade estrutural de compostos pertencendo à família oxomolibdénio(VI). Foram estudados três métodos de aquecimento: o método hidrotérmico, de refluxo e por microondas. Foi também estudada sob condições hidrotérmicas a reacção alternativa envolvendo a utilização do composto inorgânico trióxido de molibdénio (MoO3) com os ligandos di-t-Bu-bipy, H2bpdc e pzpy. A natureza dos ligandos bidentados de azoto e/ou o método utilizado promoveram a formação de uma série de novos híbridos do tipo oxomolibdénio(VI) que claramente reflectiram a influência estruturante dos ligandos. Assim, esta tese descreve a síntese e caracterização do complexo mononuclear [MoO2Cl2(pent-pp)] , dinuclear [Mo2O6(di-t-Bu-bipy)2] e octanuclear [Mo8O22(OH)4(di-t-Bu-bipy)4] assim como dos materiais poliméricos {[MoO3(bipy)][MoO3(H2O)]}n, (DMA)[MoO3(Hbpdc)]·nH2O, [Mo3O9(pzpy)]n and [Mo2O6(pent-pp)]n (embora os detalhes estruturais deste polímero sejam ainda desconhecidos, os dados da sua caracterização remetem para um oxo-híbrido polimérico). O comportamento catalítico dos complexos e dos compostos poliméricos foi testado na reacção de epoxidação de olefinas. Os compostos [Mo3O9(pzpy)]n e [Mo2O6(pent-pp)]n deram origem a espécies activas solúveis respectivamente identificadas como os complexos oxodiperoxido [MoO(O2)2(pzpy)] e [MoO(O2)2(pent-pp)]. A maioria dos compostos aqui apresentados foram caracterizados através da utilização de técnicas de caracterização do estado sólido, nomeadamente análise elementar, análise termogravimétrica, FT-IV, RMN de estado sólido, microscopia electrónica e difracção de raio-X de pós (tanto de fontes do laboratório e/ou de sincrotrão).

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35

Suspene, Clément. "Synthèse de matériaux hybrides incorporant des ligands chélatants tétraazotés : application à la fixation de gaz." Dijon, 2007. http://www.theses.fr/2007DIJOS041.

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En 1999, de nouveaux matériaux hybrides mésoporeux incorporant des motifs organiques dans les murs d’un réseau inorganique de silice ont été découverts. Ces matériaux appelés “PMOs” (Periodic Mesoporous Organosilicas) sont synthétisés selon le procédé sol-gel en présence d’un tensioactif structurant à partir de précurseurs organiques portant au moins deux chaînes alcoxysilylées hydrolysables. Lorsque les entités organiques sont des molécules chélatantes, leur distribution homogène dans le réseau poreux permet d’assurer une bonne accessibilité des sites actifs à différents substrats, comme les cations métalliques, plus particulièrement les métaux de transition (Cu2+) et les molécules gazeuses (O2, CO). En utilisant un tensioactif non-ionique de type copolymère tribloc, des matériaux incorporant dans les murs du réseau inorganique un tétraazamacrocycle (cyclame, cyclène) N-fonctionnalisé ont été obtenus et ils présentent le plus souvent une structuration à plus ou moins longue distance avec des mésophases de type hexagonale ou vermiculaire. Après complexation par Cu(II) et activation thermique sous vide, ces matériaux sont capables de coordiner le dioxygène et le monoxyde de carbone. Une seconde famille de complexes de cuivre, dérivés de ligands tétraazotés tripodaux de type tris(aminoethyl)amine (Tren), a été incorporée dans une matrice poreuse en utilisant un tensioactif cationique (ctab), ce qui a conduit à des solides présentant une microporosité importante. La complexation de ces matériaux sous atmosphère inerte conduit à des solides présentant des propriétés de coordination du dioxygène originales et à un adduit oxygéné du cuivre stable à température ambiante
In 1999, new mesoporous hybrid materials incorporating organic moieties in their silica inorganic framework were discovered. These materials called “PMOs” (Periodic Mesoporous Organosilicas) were synthesized from bridged-silsesquioxanes (EtO)3Si-R-Si(OEt)3 by the sol-gel process in presence of a structure directing agent. The organic chelating groups are homogeneously distributed in the porous network, which allows a good accessibility of the active sites to different substrates such as metallic cations, particularly transition metals (Cu2+), and gas molecules (O2, CO). By using a non-ionic surfactant such as triblock copolymers, the materials incorporating N-functionalized tetraazamacrocycles (cyclam, cyclen) in their walls were obtained and have shown a good organisation at short and long ranges with hexagonal or wormlike mesophases. After complexation with Cu(II) and thermal activation under reduced pressure, these materials were able to coordinate dioxygen and carbon monoxide. Another family of copper complexes, derived from tripodal tetradentate amine ligands such as tris(aminoethyl)amine (Tren), was incorporated into a porous matrix by employing a cationic surfactant (ctab). The resulting materials exhibited a high level of microporosity and their complexation under argon led to solids with original coordination properties of dioxygen and to a stable copper-dioxygen adduct at room temperature

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Perrier, Arnaud. "Ligands hybrides phosphino-alcènes par et pour la catalyse." Dijon, 2009. http://www.theses.fr/2009DIJOS052.

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Au cours de ces dernières années, la catalyse connaît un essor croissant tant au niveau académique qu’industriel parce qu’elle propose des processus de plus en plus économes en énergie, économes en atomes, à faible impact sur l’organisme et sur l’environnement. Les travaux présentés dans ce mémoire s’inscrivent dans cette démarche et ont trait à la recherche de nouveaux procédés d’hydrophosphination catalytiques. La première hydrophosphination de diènes catalysée par un complexe de titane nous a ainsi permis de synthétiser un grand nombre d’allylphosphines, avec une régiosélectivité encore jamais décrite à ce jour. Une catalyse basique, complémentaire et découlant directement de la catalyse au titane, a pu être utilisée pour effectuer l’hydrophosphination simple, rapide et efficace de diènes, ou encore d’autres composés. Enfin, les allylphosphines ou homoallylphosphines obtenues par ces deux nouvelles catalyses ont été engagées en tant que ligands dans des complexes de ruthénium qui ont montré une activité intéressante en catalyse de synthèse d’esters d’énol
These past few years, more and more interest has been given to catalysis in both academic and industrial fields. Indeed most of the recently described catalytic processes are now energy and atom economic and are also bio- and eco-compatible. The present work is dealing with new catalytic hydrophosphination methods, using an approach which responds to these ecological criteria. The first titanium-catalyzed hydrophosphination of dienes was so used to synthesize several allylphosphines, with high regioselectivities. An easy, complementary and efficient hydrophosphination of dienes and other compounds via a base-catalyzed reaction is described, directly resulting from the titaniumcatalyzed process. Finally, allylphosphines and homoallylphosphines obtained via those two methodolgies were used as ligands in ruthenium complexes which showed an interesting potential in enol esters catalyzed synthesis

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Hawthorne, Krista Leigh. "Iron-Ligand Electrokinetics towards an all-Iron Hybrid Redox Flow Battery." Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1405002859.

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38

Licitra, Edward J. (Edward Joseph). "The yeast three-hybrid system : a method for detecting ligand-protein interactions." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/38836.

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Rouge, Pascal. "Fonctionnalisation de calix[4]arènes par des chélateurs du fer et/ou une matrice inorganique : études et applications." Amiens, 2009. http://www.theses.fr/2009AMIE0118.

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L’objectif de ce travail de thèse est d’obtenir de nouveaux matériaux hybrides organique-inorganique en vue d’une application en analyse (dosage du fer). Il s’intègre dans le cadre d’un projet régional multidisciplinaire réalisé en collaboration avec deux autres équipes de l’UPJV : l’équipe MESO du LG et une équipe du LRCS. Nous avons choisi de greffer des ligands du fer(III) connus sur un macrocycle de type calix[4]arène pour la partie organique, et une silice mésoporeuse (SBA-15) pour la partie inorganique. L’intérêt du contrôle conformationnel du calix[4]arène est double : pré-organisation des ligands autour du métal, fixation sur la silice. Une stratégie convergente nous a permis d’obtenir des calix[4]arènes portant des motifs chélateurs (ICL670A, catéchols) immobilisés en conformation cône, ou 1,3-alternée selon le degré de substitution. Les études préliminaires concernant la préparation ainsi que l’application des matériaux hybrides pour la conception de nouvelles électrodes sélectives du fer sont très prometteurs. De plus, les premiers résultats biologiques obtenus par l’équipe INSERM U522 de l’Université de Rennes 1, partenaire du projet, ont mis en évidence que certains de ces calix[4]arènes possèdent une activité antiproliférative intéressante (IC50 = 6 µM) ce qui permet d’envisager d’autres fonctionnalisation afin d’optimiser cette activité biologique
The purpose of this work is to obtain new organic-inorganic hybrid materials with applications in analysis (iron titration). This work is integrated in the formation of a multidisciplinary group in the UPJV: team MESO from LG and one team from the LRCS. We have choose to graft functionnalized calix[4]arenes by well known iron(III) chelators into a SBA-15 silica matrix. The good control of calix[4]arene conformation have two interests : pre-organization of the ligands around the metal, grafting to the silica. A convergent strategy allows us to obtain calix[4]arenes bearing irons chelators (ICL670A, catechols) immobilized in cone or 1,3-alternated conformation. Preliminary results concerning the synthesis and use of these materials in sensors are very promising. Moreover, first biological results obtained by our partners of the Université de Rennes 1 have shown that some calix[4]arenes have a good antiproliferative effect (IC50 = 6 µM)

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Sommer, Samantha. "Hybrid Metal-Ligand Hydrogen-Bonded (MLHB) Architectures Based on the Quinolone Subunit: Understanding and Expanding the Accessible Space of Supramolecular Systems." Thesis, University of Oregon, 2015. http://hdl.handle.net/1794/19298.

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Despite the prevalence of supramolecular architectures derived from metal-ligand or hydrogen-bonding interactions, few studies have focused on the simultaneous use of these two strategies to form discrete metal-ligand hydrogen-bonded (MLHB) assemblies. The design, synthesis, and characterization of 2-quinolone based hybrid subunits, 7-DPQ and 5-PYQ, that contain phosphine and pyridyl metal binding sites, respectively, is reported. Both subunits give two-fold symmetric hydrogen-bonded tectons that assemble with metal precursors to give hybrid MLHB structures. Treatment of [Cp*RhCl2]2 with the 7-DPQ subunit yields hybrid MLHB assemblies with closed topology. 1H diffusion ordered spectroscopy experiments established the stability of the structures in solution, and the measured hydrodynamic radii match those determined crystallographically, suggesting that the closed topology is maintained in solution and the solid state. In order to further explore possible MLHB architectures and test the selectivity boundaries of our quinolone-based subunits we report the selective assembly of 5-PYQ with mono- and bis-platinated anthracene precursors. Addition of 5-PYQ to [1-trans-Pt(PEt3)2NO3]-8-chloroanthracene yielded a hybrid MLHB structure with preorganization for a hybrid MLHB polymer. Despite the systems preorganization for the hybrid polymeric structure the assembly of 5-PYQ with 1,8-bis(trans-Pt(PEt3)2NO3)anthracene selects only for one discrete closed self-assembled macrocycle. The strong π-π stacking interactions of the 5-PYQ subunits erode the hydrogen-bonding fidelity to favor ambidentate coordination modes of 5-PYQ and give the non-hybrid macrocycle. In the course of investigating the intricacies of hybrid MLHB supramolecular structures we observed that, in addition to metal-ligand and hydrogen-bond interactions, the π-π stacking interactions of the 7-DPQ and 5-PYQ subunits played a critical role in determining the final assemblies. In fact, the prominent π-π interactions were typically found to be more favorable than the quinolone interligand hydrogen-bonding interactions. These results contribute to the overall knowledge of the design principles, synthesis, characterization, and fundamental assembly trends when exploiting both hydrogen-bonding and metal-ligand interactions to form stable supramolecular architectures. These studies have provided the foundation for expanding the accessible space of supramolecular chemistry to include rationally designed hybrid MLHB systems to give structures that more closely mimic the complex supramolecular systems observed in Nature. This dissertation includes both previously published/unpublished and co-authored material.
10000-01-01

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Massue, Julien. "Ligands électroactifs à base de tétrathiafulvalène ou analogues : valence mixte et récepteur moléculaire." Rennes 1, 2005. http://www.theses.fr/2005REN1S099.

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Ce travail de thèse porte sur la synthèse et la caractérisation physico-chimique (structurale, électrochimique, spectroscopique, magnétique) de nouveaux matériaux hybrides organique-inorganique basés sur le motif électroactif tétrathiafulvalène (TTF). L'originalité de ces composés, précurseurs de matériaux moléculaires conducteurs réside dans l'incorporation de la fonction de coordination β-dicétonate ou acétylacétonate, bien connue pour complexer de nombreux métaux. La seconde partie de la thèse présente la synthèse de capteurs et de récepteurs moléculaires comportant des tétrathiafulvalènes vinylogues, molécules bien connues pour présenter des mouvements moléculaires rapides et réversibles associés à un transfert d'électron, à l'origine des propriétés des nano-objets que nous envisageons.

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Pütz, Anna-Maria [Verfasser]. "Phosphonate ligands in extended inorganic hybrids and as radical units in complexes / Anna-Maria Pütz." Mainz : Universitätsbibliothek Mainz, 2015. http://d-nb.info/1075871387/34.

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Delain, Lise. "Synthèse d'alcynylphosphonates : application pour l'immobilisation de ligands aromatiques sur supports inorganiques." Caen, 2006. http://www.theses.fr/2006CAEN2029.

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Ce mémoire est consacré à l’étude de l’immobilisation de complexes formés par un ligand organique complexé à un métal et son application en catalyse hétérogène. L’immobilisation de ce complexe est effectuée sur oxyde métallique (alumine) en employant la fonction phosphonate comme point d’encrage. Nous avons synthétisé des espaceurs de longueur ajustable afin de pouvoir contrôler la distance entre le support et le ligand immobilisé. Une étude du greffage de phosphonate sur alumine et zéolithe a été effectuée. Les matériaux obtenus sont caractérisés par RMN MAS, IR et par étude de stabilité thermique et chimique. Le greffage est effectué avec un bon taux et il est stable. La mise au point de la synthèse d’alcynylphosphonates possédant différentes longueurs de chaînes est le premier point de notre stratégie. Pour synthétiser ces molécules nous avons utilisé l’alcool ou le bromure de propargyle comme source de tripple liaison. Le ligand est ensuite fonctionnalisé soit par une réaction de couplage de Sonogashira soit par une réaction de “click chemistry” avec les alcynes terminaux. La mise au point de ces deux réactions, la formation des complexes correspondants ainsi que l’immobilisation de ces espèces sont détaillées. Des tests sont effectués dans la réaction de Heck oxydante, afin d’évaluer l’activité catalytique du ligand immobilisé. Malgré une cinétique plus lente, l’activité est conservée, la stratégie d’immobilisation a donc été validée
This work deals with the complex immobilisation and its application in heterogeneous catalysis. The grafting of this complex is managed on metal oxide (alumina) with using the phosphonate group as anchoring function. Spacers of adjustable length were synthesised in order to be able to space the ligand from the support. A Study of phosphonate grafting on alumina and zeolite was developed. The obtained materials were characterized by MAS NMR, IR, and by thermal and chemical stability. The grafting was managed with a good rate, and it was stable. The synthesis of adjustable length alcynylphosphonate was the first point of our strategy. To synthesise these molecules we used propargyl alcohol or bromide as a source of triple bond. The ligand is then functionalized by Sonogashira cross coupling or by “click” chemistry reaction with the alkyne function. The optimisation of this both reaction, the complex formation and their immobilisation were exposed. Catalytic tests were managed in the oxidative Heck reaction in order to estimate the catalytic activity of the grafted ligand. Despite a lower rate of the reaction, the activity is conserved, so the strategy of the immobilisation is confirmed

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Benchouaïa, Rajaa. "Vers de nouveaux métallo-récepteurs : synthèse et études de ligands hybrides hexaphyrine-cyclodextrine." Thesis, Rennes 1, 2019. http://www.theses.fr/2019REN1S116.

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Les hexaphyrines sont constituées de six unités pyrroliques et présentent différents types d'aromaticité, à l'origine de leurs remarquables propriétés de coordination. Cependant, les complexes sont décrits majoritairement sur des hexaphyrines « nues ». De plus, l'induction de chiralité sur un anneau de Möbius n'en est qu'à ses prémices. Dans ce contexte, nous explorons les propriétés de coordination des hexaphyrines « chapeautées ». Plus particulièrement, notre objectif consiste à élaborer des ligands hybrides, dont les unités hexaphyrine et cyclodextrine sont liées de manières covalentes. Pour ces hybrides, l'hexaphyrine peut être chapeautée par une à deux cyclodextrines, via six pontages. Dans un premier temps, les études de coordination menées sur la version triplement pontée ont permis de mettre en avant la forte rigidité du système, empêchant une éventuelle adaptation pour l'incorporation d'ions métalliques tels que le ZnII, CdII, HgII, PdII. Dès lors, la synthèse, inédite, des édifices doublement pontés a permis d'avoir accès au premier anneau de Möbius ponté par une cavité. De surcroit, des complexes de ZnII et HgII ont été obtenus. Curieusement, ces ligands présentent 3 sources de chiralité tel un totem. Nous avons réussi à obtenir un excès diastéréoisomérique de 94%, pour la communication en interne entre la chiralité planaire et l'anneau de Möbius, sur les complexes obtenus. De plus, ces complexes ont permis d'avoir une communication de la cyclodextrine quantifiée avec un e.d. de 60%. Par la suite, la fonctionnalisation a été encore plus élaborée en modifiant le cœur de l'hexaphyrine, les positions méso, et la cyclodextrine. Ces hybrides ont ainsi une sphère de coordination plus favorable à la coordination d'ions métalliques. Les premiers essais sont très encourageants. Finalement, ces ligands hybrides pourraient être des récepteurs allostériques ou des catalyseurs, ce qui est en cours de développement au laboratoire
Hexaphyrins are constituted by six pyrrole units and present different types of aromaticity at the origin of their remarkable coordination properties. However, complexes are mainly described on “naked” hexaphyrins. Besides, the induction of chirality on a Möbius ring is still in its infancy. In this context, we explore the coordination properties of ''capped'' hexaphyrins. More particularly, our objective consist to develop hybrid ligands, where hexaphyrin and cyclodextrin units are covalently linked. For these hybrids, the hexaphyrin can be capped by one or two cyclodextrins, until six linkages. First, coordination studies realized on the triply linked ligands, enabled to show the strong rigidity of the system, avoiding any adaptation for the incorporation of metal ions such as ZnII, CdII, HgII, PdII. Thus, the unprecedented synthesis, of the doubly linked ligands, enabled to have access to the first Möbius ring capped by a cavity. Moreover, complexes of ZnII and HgII were obtained. Interestingly, these ligands present three sources of chirality as a totem. We succeeded to obtain a diastereomeric exces of 94%, for the communication between the planar chirality and the Möbius ring, on the complexes. Besides, these complexes enabled to have a communication from the cyclodextrin quantified by a d.e. of 60%. Then, the functionalisation became more sophisticated by modifiying the hexaphyrin core, the meso positions, and the cyclodextrin. These hybrids have hence a coordination sphere which is more favorable to metal ions coordination. These first tests are really encouraging. Ultimately, these hybrid ligands would lead to allosteric receptors and catalysts, which is the concern of our researches

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Dubois, Géraud. "Elaboration et étude de matériaux hybrides organique-inorganiques monophasés incorporant des motifs chélatants. Application pour la fixation du dioxygène." Montpellier 2, 1999. http://www.theses.fr/1999MON20043.

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Guhrenz, Chris, Vladimir Sayevich, Florian Weigert, Eileen Hollinger, Annett Reichhelm, Ute Resch-Genger, Nikolai Gaponik, and Alexander Eychmüller. "Transfer of Inorganic-Capped Nanocrystals into Aqueous Media." American Chemical Society, 2017. https://tud.qucosa.de/id/qucosa%3A33352.

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We report on a novel and simple approach to surface ligand design of CdSe-based nanocrystals (NCs) with biocompatible, heterobifunctional polyethylene glycol (PEG) molecules. This method provides high transfer yields of the NCs into aqueous media with preservation of the narrow and symmetric emission bands of the initial organic-capped NCs regardless of their interior crystal structure and surface chemistry. The PEG-functionalized NCs show small sizes, high photoluminescence quantum yields of up to 75%, as well as impressive optical and colloidal stability. This universal approach is applied to different fluorescent nanomaterials (CdSe/CdS, CdSe/CdSCdxZn1–xS, and CdSe/CdS/ZnS), extending the great potential of organic-capped NCs for biological applications.

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Beck, John Benjamin. "Using the Metal-Ligand Interaction to Construct Complex Supramolecular Polymer Architectures." Case Western Reserve University School of Graduate Studies / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=case1112815582.

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Venot, Pierre-Etienne. "Synthèse stéréosélective d'Hybrides de lobéline et de ligands naturels des récepteurs nicotiniques centraux à l’acétylcholine." Thesis, Paris 11, 2015. http://www.theses.fr/2015PA114813/document.

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Au cours de ce travail, nous avons développé des voies de synthèses convergentes et énantiosélectives en vue de préparer des analogues pyrrolidiniques des alcaloïdes de Lobelia comme nouveaux ligands des récepteurs nicotiniques à l’acétylcholine. Deux familles de ligands ont été réalisées par des méthodes d’élongation mono- ou bi-directionnelle basées respectivement sur des stratégies de désymétrisation précoce ou tardive au départ du succinaldéhyde.La première partie de ce manuscrit aborde la conception d’hybrides de lobéline, nicotine et d’agonistes naturels. Ces structures originales ont été obtenues diastéréosélectivement grâce à un intermédiaire commun issu d’une élongation monodirectionnelle du succinaldéhyde. Cette voie exploitera la chimie des iminiums masqués. La mise au point de cette synthèse s’est enrichie par la découverte et la valorisation d’une nouvelle famille de ligands chimériques.La seconde partie étudie la voie d’élongation bidirectionnelle basée sur des réactions de double aza-Michael suivies de la réduction désymétrisante tardive de pyrrolidines 2,5-phénacyl méso et pseudo-méso. Cette stratégie asymétrique s’inscrit dans une démarche d’économie d’atomes et d’étapes. La perspective majeure de ce travail est l’évaluation par électrophysiologie sur différents sous-types de récepteurs à l’acétylcholine d’une sélection de ligands hybrides.Les études de RSA menées sur ces familles de composés de haute homologie structurale permettront in fine d’améliorer les modèles prédictifs décrivant les transitions allostériques des récepteurs nicotiniques à l’acétylcholine
During this PhD work, convergent and diastereoselective routes for the preparation of pyrrolidine Lobelia alkaloid analogues have been developed as novel neuronal nicotinic receptor ligands. Two families of ligands have been synthesized by a strategy of mono- or bi-directional elongation of the succinaldehyde including early or late desymmetrization process respectively.The first part of this manuscript is dedicated to the preparation of hybrids of lobeline, nicotine and other natural agonists. These original structures have been diastereoselectively obtained thanks to a common intermediate resulting of the mono-elongation of succinaldehyde. This synthetic pathway uses the chemistry of masked iminium. The development of this strategy has been enriched by the discovery and the valorisation of a new chimeric ligand family.The second part studies the “bidirectional” elongation route, based on a ring-closing double aza-Michael reaction followed by the desymmetrizing reduction of meso and pseudo-meso 2,5-diphenacyl pyrrolidines. This asymmetric strategy constitutes a step- and atom-economical approach. The major perspective of this work is the biological evaluation of selected ligands by electrophysiology made on different nAChR subtypes.The SAR studies realized on these structurally homologue ligand families could allow the improvement of the predictive molecular models describing the allosteric conformations of the nAChRs

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Cerneaux, Sophie. "Matériaux hybrides auto-organisés fonctionnels à complexant macrocyclique et fonction urée pour la réalisation de membranes à transport facilité : étude du transport de solutes biologiques." Montpellier 2, 2003. http://www.theses.fr/2003MON20131.

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Benyahya-Bouayad, Sofia. "Immobilisation de ligands par voie sol-gel pour l'arylation de nucléophiles oxygénés catalysée au cuivre." Montpellier 2, 2009. http://www.theses.fr/2009MON20082.

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Nous avions pour objectif de mettre au point une voie permettant la synthèse de diaryléthers par catalyse au cuivre en utilisant des ligands immobilisés sur des matériaux silylés organiques-inorganiques élaborés par voie sol-gel. L'intérêt de ces systèmes hétérogènes réside dans le fait qu'ils sont recyclables et réutilisables, moins polluants et moins toxiques grâce à leur grande capacité de piégeage du catalyseur métallique. Ce point est particulièrement important pour une utilisation des diaryléthers obtenus en industrie pharmaceutique. Nous sommes parvenus à synthétiser par voie sol-gel des matériaux incorporant des ligands de type bipyridine ou β-dicarbonyle. Ces matériaux ont été ensuite appliqués en arylation des phénols par des iodures et bromures d'aryls catalysée au cuivre. Les nouveaux catalyseurs hétérogènes ont permis d'obtenir de bonnes performances en arylation de nucléophiles oxygénés et aussi en termes de récupération et de réutilisation. Par ailleurs, les produits diaryléthers obtenus ne sont pas pollués par des traces de cuivre. La méthode que nous avons mise au point s'avère donc particulièrement compétitive en termes de coût, de pollution et de toxicité résiduelle. Elle constitue à notre connaissance le premier exemple de ligand supporté sur silice par voie sol-gel appliqué en arylation de phénols catalysée au cuivre
Our aim was to develop a way to synthesize diarylethers using copper catalyted ligands immobilized on silyl-organic inorganic materials prepared by sol-gel. The interest of these heterogeneous systems is that they are recyclable and reusable, less polluting and less toxic due to their ability to sequester metal catalyst. This is particularly important for use of diaryléthers obtained in pharmaceutical industry. We managed to synthesize by sol-gel process materials incorporating bipyridine or β-dicarbonyl type ligands. These materials were then applied in copper-catalyzed arylation of phenols by aryl iodides and bromides. The new heterogeneous catalysts have yielded good results in arylation of oxygen nucleophilies and also in terms of recovery and reuse. In addition, diaryléthers products are obtained "clean" of copper traces used in catalysis. The method we developed is therefore particularly competitive in terms of cost, pollution and residual toxicity. It is to our knowledge the first example of ligand supported on silica by sol-gel and applied in copper-catalyzed arylation of phenols

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Dissertations / Theses on the topic 'Hybrid ligands'

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