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1
Dubberley, Stuart R. "New calix[4]arene metal complexes." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365290.
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Neshat, Abdollah. "Group V Imido Complexes Bearing Mono-Anionic Acetophenone Imine Ligands." University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1302269375.
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梁華雄 and Wa-hung Leung. "Oxidation chemistry of ruthenium and manganese complexes of multi-anionic chelating ligands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1989. http://hub.hku.hk/bib/B31231627.
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Leung, Wa-hung. "Oxidation chemistry of ruthenium and manganese complexes of multi-anionic chelating ligands /." [Hong Kong : University of Hong Kong], 1989. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12355197.
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Clevenger, Margo. "Synthetic Routes to 3-Fold Symmetric Tridentate Oxygen Donor Ligands." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36964.
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The class of ligands represented by [CpCo(P(O)(OR)2)3]-, L- , were first synthesized by W. Kläui in 1977. These ligands have been found to coordinate to a variety of low and high oxidation state metals through the use of its three P=O oxygen atoms as donors. The ligands act as mono-anionic six electron donors which make them similar to the more widely known cyclopentadienyl ligands, (C5H5-xRx)-, but have electronic properties like those of fluoride or oxide. Also, it has been found that the coordination chemistry of L- resembles the unsubstituted tris(pryrazolyl)hydroborato six electron ligand, (RB(pz)3)-. All three of these ligands can be modified by changing the substituent R. The Kläui ligand offers a good opportunity to synthesize a chiral derivative.
In the process to obtain the chiral version, (cyclopentadienyl)tris(biphenyl-phosphito-P)cobaltate(1-), 18, was synthesized from 2,2'-biphenol. This was characterized through NMR, mass spectroscopy, and XPS. Next, a racemic version, (cyclopentadienyl)tris(biphenylphosphito-P)cobaltate(1-), 17, was synthesized from (±)1,1â -bi-2-naphthol. A one-pot synthesis for the rac-binaphthyl phosphite derivative was developed with an increased yield from the previously published synthesis. The racemic version of the ligand was characterized by NMR and mass spectroscopy. The chiral version has not yet been synthesized, however, by following the developed procedure for the non-chiral version, the ligand could be synthesized from optically active 1,1'-bi-2-naphthol.Master of Science
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Chan, Siu-chung, and 陳兆聰. "Photoluminescent and electroluminescent properties of neutral platinum(II) complexes containing alkynyl and multi-anionic ligands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31245171.
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Alliger, Glen E. (Glen Edward). "Synthesis and investigation of hexacarboxamide cryptands as anionic binucleating ligands by Glen E. Alliger." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/62100.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2010.Vita. Cataloged from PDF version of thesis.
Includes bibliographical references.
We have investigated the use of hexacarboxamide cryptands as sextuply anionic binucleating ligands. Two homobimetallic complexes of a t-butyl-substituted cryptand, featuring manganese(II) ion and cobalt(II) ions, have been synthesized. The manganese species features a bridging hydroxide ligand; both of these species have been structurally characterized, though complete characterization was not possible due to the compounds' impurity. A highly soluble hexacarboxamide cryptand, featuring dipropoxyphenoxyl substituents, was synthesized for the first time, and has been structurally characterized. The structure features a two-dimensional hydrogen bonding network, resulting in infinite sheets of cryptand units. We have synthesized a dicobalt(II) complex of this ligand. This compound features the metal centers in cofacial trigonal monopyramidal geometries, with an intermetallic distance in excess of 6 A. This marks the first time that such a species has been fully characterized. Despite the void between the metal centers, elucidation of constructive reactivity was a challenge, though insertion of cyanide under forcing conditions was achieved. This dicobalt(II) p-cyano complex was also structurally characterized. Using the methodology set forth for the synthesis of the dicobalt(II) complex of the soluble cryptand, we have synthesized a series of complexes of this ligand, featuring manganese(II), iron(II), nickel(II), and zinc(II). These compounds were structurally characterized, and were found to be isomorphous with the dicobalt(II) complex. A comparison of the structures is drawn. These compounds have also been characterized by a variety of methods, including SQuID magnetometry, cyclic voltammetry, EPR, and, in the case of the diiron complex, Mbssbauer spectroscopy. Also reported is work toward a diiron(III) complex; the M6ssbauer spectrum of this species is reported. In analogy to the pt-cyano complex of the dicobalt complex above, a p-cyano complex of the diiron(II) was synthesized and structurally characterized. Investigations into the utility of the initial t-butyl substituted cryptand as a ligand have also been made. Initial results indicate that monometalation of this ligand is possible, and treatment of a putative monocobalt(II) complex with tetrabutylammonium cyanide suggests that the cyanide-bound product is in equilibrium with the free complex.
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Avedis, Ani. "A high-throughput method for screening of protein binding behavior of multimodal anionic exchange ligands." Thesis, Uppsala universitet, Analytisk farmaceutisk kemi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-434809.
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The biopharmaceutical industry is constantly developing biological drugs, resulting in increased levels of product related impurities having similar characteristics as the target. The aim of the ligand project was to address future challenging purifications by developing new ligands for future resins for the biopharmaceutical industry. The purpose of this study was to develop a high-throughput screening method and use it to compare 15 novel multimodal anionic exchange ligand analogues with two reference ligands, for future polishing steps in the downstream process. The protein binding behavior of the ligands were studied with alkaline phosphatase, human serum albumin, α-chymotrypsinogen A and a monoclonal antibody as model proteins, at various pH values and salt concentrations. The selection process of the model proteins was based on stability studies, a study of their adsorption to the 96 well plate, and their binding behavior on three of the ligand analogues and one reference ligand. The percent protein bound to the ligands at the various conditions was calculated and presented in plots in order to study their binding behaviors. The calculated values were also used in order to evaluate the results in principal component analysis, creating chromatographic diversity maps. The maps were used to get an overview of the differences and similarities of the ligand analogues compared to the reference resins, which can be used for selecting ligands for future research and biomanufacturing. Four analogues and one reference ligand were also studied in a column format where different gradients were used, which confirmed the obtained results in the plate experiments.
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Dyke, Alan. "Novel Câ‚‚-symmetric N,N-donor ligands and the anionic thia-Fries rearrangement of aryl triflates." Thesis, University of Bristol, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404435.
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高寶鴻 and Po-hung Ko. "Syntheses, structures and reactivities of some ruthenium, manganese and osmium complexes of non-porphyrin chelating multi-anionic ligands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31235906.
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Ko, Po-hung. "Syntheses, structures and reactivities of some ruthenium, manganese and osmium complexes of non-porphyrin chelating multi-anionic ligands /." Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18611862.
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Ho, Kwok-keung Paul. "Molecular structures and physicochemical properties of some chiral and helical transition metal complexes with polypyridines and tetradentate anionic ligands /." Hong Kong : University of Hong Kong, 1996. http://sunzi.lib.hku.hk/hkuto/record.jsp?B17545675.
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Kelsen, Vinciane. "Greffage de complexes organométalliques sur anions hydroxyborates : application à la transformation des oléfines." Thesis, Lyon 1, 2010. http://www.theses.fr/2010LYO10280.
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Cette thèse présente le greffage de complexes organométalliques sur des anions hydroxyborates. Ces ligands originaux sont susceptibles de conférer des propriétés particulières à la sphère de coordination du métal. Leur caractère anionique pourrait permettre l'immobilisation des catalyseurs dans une phase liquide ionique. La majeure partie des travaux a porté sur la réactivité des anions hydroxyborates avec les métaux du groupe IV de la classification périodique. Les complexes alkyles du zirconium et de l'hafnium réagissent avec la fonction hydroxyle de l'anion par protonolyse de la liaison métal-alkyle. La résolution par diffraction des rayons X de la structure des complexes métallocènes [Cp2MMe(OB(C6F5)3)]- [PPN]+ (M = Zr et Hf) a confirmé la nature covalente des liaisons M-O et B-O et donc l'intérêt des anions hydroxyborates comme ligands de complexes organométalliques. Cette réactivité a ensuite été déclinée sur différents précurseurs du zirconium et de l'hafnium. Le complexe ionique [Ti(OiPr)3(OB(C6F5)3]-[PPN]+ a été synthétisé à partir d'un complexe alkoxy du titane par une réaction d'échange de ligands. Ce complexe activé par le triéthylaluminium dimérise sélectivement l'éthylène en butène-1 en milieu liquide ionique. L'extension du concept à d'autres métaux de la classification périodique : aluminium, fer, molybdène, a été abordée. Deux complexes anioniques du molybdène ont notamment été isolés et sont des catalyseurs de métathèse des oléfinesThis thesis presents the use of hydroxyborate anions as anchors for organometallic complexes. These original ligands might confer particular properties to the coordination sphere of the metal. Their anionic nature might also allow the immobilization of catalysts in ionic liquids. The main part of this work dealt with the reactivity of hydroxyborate anions with group IV metals. Zirconium and hafnium complexes reacted with the hydroxyl function of the anion by protonolysis of the metal-alkyl bond. Resolution of the structure of metallocene complexes [Cp2MMe(OB(C6F5)3)]-[PPN]+ (M = Zr and Hf) by X-Ray diffraction confirmed the covalent nature of M-O and B-O bonds and so the relevance of hydroxyborate anions as ligands for organometallic complexes. Then, this reactivity was extended to different zirconium and hafnium precursors. The ionic complex [Ti(OiPr)3(OB(C6F5)3)]- [PPN]+ was synthesized from an alkoxy titanium complex by a ligand exchange reaction. This complex activated by triethylaluminium selectively dimerized ethylene into 1-butene in ionic liquids. Extension of the concept to other metals such as aluminum, iron and molybdenum, was studied. Two anionic molybdenum complexes were isolated and are catalysts for olefin metathesis
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Davies, Joanna Kay. "Rat liver fatty acid binding protein structure and function : the targeting of FABP-bound ligands to anionic interfaces." Thesis, University of Southampton, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393911.
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Clark, Alec Ian. "Synthesis and characterisation of some new complexes of molybdenum(II) and tungsten(II) containing anionic and neutrual sulphur donor ligands." Thesis, Bangor University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245172.
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Tanaka, Kiyotaka. "Anionic ligand exchange in Hoveyda-Grubbs ruthenium benzylidenes." Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443802.
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Hopkins, Peter K. "Novel tripodal ligands designed to complex anions." Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249200.
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Pomećko, Radosław Arnaud Françoise Bochenska Maria. "Calix[4]arènes phosphoniums et ammoniums Synthèse et étude des interactions ligand-anion /." Strasbourg : Université Louis Pasteur, 2007. http://eprints-scd-ulp.u-strasbg.fr:8080/838/01/POMECKO_Radoslaw_2007.pdf.
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Thèse de doctorat : Chimie supramoléculaire : Strasbourg 1 : 2007. Thèse de doctorat : Chimie supramoléculaire : Gdansk University of Technology : 2007.Thèse soutenue en co-tutelle. Titre provenant de l'écran-titre. Notes bibliogr.
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Kingston, Justine E. "Redox-active host molecules for anion recognition." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320669.
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Guérin, Charles. "Synthèse et valorisation de ligands dipyrrométhène bis-triazole." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1254/document.
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Analogues structuraux des porphyrines et des Salens, des ligands de type dipyrrométhène bis-phénol ont été étudiés dans notre groupe, notamment sous forme de complexes pour la catalyse d'oxydation. L'activité catalytique de ces complexes étant faible, il a été proposé de remplacer les phénols par des triazoles. L'objet de cette thèse était d'étudier et de valoriser une nouvelle famille de ligands dipyrrométhène bis-triazole.Plusieurs voies de synthèse ont d'abord été étudiées et optimisées pour accéder à ces nouveaux ligands. Nous nous sommes attachés ensuite à valoriser ces nouveaux ligands selon plusieurs axes.Un de ces ligands a été testé en reconnaissance d'anions, ainsi que les dérivés monotriazolium et bis-triazolium. Les triazoliums ont également permis l'accès à des métallocomplexes carbéniques, qui ont été étudiés.Par ailleurs, les métallocomplexes des dipyrrométhène bis-triazole ont été préparés et caractérisés, y compris par électrochimie. Des essais d'utilisation en oxydation ont été entrepris. Enfin, la synthèse de BODIPYs® liposolubles et hydrosolubles a été réalisée. Les propriétés optiques ont été mesurées puis ces dérivés fluorescents ont été testés pour le marquage fluorescent de cellules HeLaKnown as structural analogues of porphyrins and Salens, dipyrromethene bis-phenol-type ligands have been studied in our group, especially as complexes for oxidation catalysis. Due to the poor catalytic activity of these complexes, it has been proposed to replace the phenol moieties with triazoles. The purpose of this thesis was to study and develop a new family of dipyrromethene bis-triazole ligands.Several synthetic routes were first investigated and optimized to reach these new ligands. We then have endeavoured to add value to these new ligands along several lines.The ligand has been tested in anion recognition, as well as monotriazolium and bis-triazolium derivatives. The triazoliums also allowed access to carbene metallocomplexes that were studied.Furthermore, dipyrromethene bis-triazole metallocomplexes were prepared and characterized, notably by electrochemistry. Oxidation catalysis tests were undertaken.Finally, the synthesis of liposoluble and hydrosoluble BODIPYs® was performed. Their optical properties were measured and these fluorescent derivatives were tested for the fluorescent labeling of HeLa cells
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Caro, Catherine F. "N- and C-centred anionic ligand complexes of the alkaline earth metals." Thesis, University of Sussex, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263911.
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Atmani, Rafiqui Chahlae. "Approche polymétrique à base d’anions polynitrile : vers une nouvelle génération de matériaux à transition de spin." Brest, 2011. http://www.theses.fr/2011BRES2044.
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Ces dernières années de nombreux travaux ont été dédiés aux matériaux à transition de spin qui présentent des potentialités pour le stockage de l’information en raison de leurs propriétés physiques commutables : métastabilité thermique et optique. Dans ce contexte, l’objectif de notre travail est de concevoir de nouveaux systèmes à transition de spin de dimension élevée. Nous avons envisagé de combiner autour du cation métallique Fe (II) deux types de ligands pontants : des co-ligands pontants neutres mono ou polydentates, d’une part, et des anions polynitrile pontants, d’autre part. Ainsi, ce mémoire est divisé en trois chapitres. Afin de bien comprendre les objectifs de ce travail, le premier chapitre est composé de deux parties. La première partie est consacrée â la présentation générale des propriétés des composés à transition de spin du Fe (II) et aux différents paramètres influençant leurs caractéristiques. Dans la deuxième partie, nous avons présenté une nouvelle série d’anions polynitrile ainsi qu’un nouveau mode d’accès à ses anions. Dans le deuxième chapitre, nous avons présenté une série de cinq nouveaux dérivés présentant des architectures originales, allant de systèmes 1D aux systèmes 3D. Le troisième chapitre a été consacré, dans un ?premier temps à l’association autour du cation métallique Fe (II) de dianions polynitrile (tcpd2- et tcno2-) et du co-ligand bpym qui a conduit â trois nouveaux polymères puis dans un deuxième temps nous avons présenté, le nouveau composé [Fe2(bpym)(tcnopr)4] possédant à la fois une structure originale tridimensionnelle et b propriété de transition de spin. Nous avons réalisé, des études de photocristallographie et de photomagnétisme à basse température pour ce dernierIn recent years much work has been dedicated to the spin transition materials that have the ability to save information due to their physical commutable properties: thermal and optics metastability. In this context, the target of our work was to design new spin transition systems of high dimensionality. We have decided to combine around the metal cation Fe (II) two types of bridging ligands: mono or polydentate neutral bridging co-ligands on one hand and bridging polynitrile anions on the other hand. Thus, this thesis is divided into three chapters. In order to understand the objectives of this work, the first chapter consists of two parts. The first part is devoted to presenting general properties of spin transition compounds of Fe (II) and the various parameters influencing their characteristics. In the second part, we presented a new series of polynitrile anions, and a new way to access to these anions. In the second chapter, we presented a series of five new compounds from 1D to 3D systems, with the original architecture. The third chapter is devoted firstly to the association around the metal cation Fe (II) of dianions polynitrile (tcpd2 and tcno2) and the co-ligand bpym leading to three new polymers and in a second time we have introduced the new compound [Fe2(bpym)(tcnopr)4] presenting original 3D crystal structure and spin transition properties together. We performed photocristallographic and photomagnetic studies at low temperature for this latter compound
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Deguenon, Diane. "Etude des anions squarate et croconate : complexes métalliques de ces ligands." Toulouse 3, 1990. http://www.theses.fr/1990TOU30074.
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Les anions squarate et croconate, membres de la famille des oxocarbones, sont caracterises par un cycle aromatique. Ils pourraient donc constituer, comme l'ion oxalate, des ligands interessants pour les metaux de transition et permettre des echanges magnetiques entre les metaux qu'ils pontent. La premiere partie de ce travail est relative a l'etude des ligands et de certains derives soufres. Par voie electrochimique, des anions radicaux sont generes. La formation de radicaux par irradiation de monocristaux de csnac#5o#5 a permis de pieger a 77 k, une paire radicalaire dont l'etude par rpe sur monocristal est reportee. Par ailleurs, l'irradiation de complexes de platine(ii) en presence d'ions hydrogenosquarate (monocristal) ou hydrogenocroconate (poudre) cree un centre paramagnetique platine(iii) dont le comportement a 77 k, etudie par rpe sur monocristal, est egalement presente. L'etude de la decomposition photochimique de l'acide croconique en milieu aqueux montre qu'elle conduit aux acides oxalique et mesoxalique. Un mecanisme faisant intervenir l'oxygene singulet permet d'expliquer les resultats obtenus lors de la synthese des complexes metalliques. Enfin, la synthese et l'etude des proprietes magnetiques de nouveaux complexes polymetalliques des acides oxalique, squarique ou croconique sont reportees. Les premiers dimeres de l'acide squarique et du cuivre(ii) ont ete caracterises grace a leur structure moleculaire cristalline aux rayons x. De plus, une chaine alternee d'heisenberg a ete obtenue. Les structures cristallines aux rayons x des premiers complexes a ligands mixtes du cuivre(ii) ou du manganese(ii) avec l'acide croconique sont presentees. En outre les proprietes magnetiques de tous les complexes polymetalliques synthetises sont presentees et discutees dans ce memoire
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Pace, Stuart. "Guanidines and their anions : versatile ligands for metallo-organic chemistry." Thesis, University of Edinburgh, 2000. http://hdl.handle.net/1842/15566.
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There are a large number of highly stable systems which are isostructural and isoelectronic to carboxylates. One of these, amidinates, the 1,3-nitrogen analogues of carboxylates, show a rich and varied coordination to both main group and transition metals. However, the triaza analogues, substituted guanidinates, had received little or no attention as ligands prior to this work, in which the ligand chemistry of neutral, mono- and dianionic guanidines has been explored. The synthesis and characterisation of tri-substituted guanidines containing a variety of alkyl (iPr, lBu, Cyx) and aryl (Ph, p-tol) substituents is described herein. Preparation of the homochiral substituted N,N',N"-tris((s)-(-)-amethylbenzyl)guanidine and the X-ray crystal structure of its HPF6 salt are also presented. In the solid state the central CN3 unit exhibits local C3 symmetry and has steric elements on one of the plane resulting in two stereochemically different faces. The formation of tetra-substituted N,N-diethyl-N',N"-diphenylguanidine is also detailed. Formation of complexes containing neutral guanidine ligands was achieved in the reactions of N,N',N"-triphenylguanidine with CoCl2 and Ag(SO3CF3). The complexes formed, [Co{PhN=C(NHPh)2]2Cl2] and [Ag{PhN=C(NHPh)2}2][SO3CF3] respectively, were characterised by X-ray crystallography and found to contain monodentate guanidine ligands bound through their imine nitrogen alone. The cobalt complex adopts pseudo-tetrahedral geometry while [Ag{PhN=C(NHPh)2}2] is perfectly linear at silver with the triflate acting only as a counterion. Cleavage reactions of the ruthenium chloro-bridged dimers [(p-cymene)RuCl2]2 and [Cp*RuCl2]2 with various tri-substituted guanidines were undertaken. Two product obtained from these reactions, namely [(p-cymene)Ru{h2-(iPrN)2CNHiPr}Cl] and [Cp*Ru{(h6-p-tol)N=C(NHp-tol)2}]+, were characterised by X-ray crystallography. The first of these contains a ruthenium centre with a h6-arene, terminal chloride and monodeprotonated chelating guanidinate ligand. Meanwhile the second is a sandwich compound in which the guanidine is bound through an arene substituent and not one of its nitrogens.
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Hart, John Stewart. "Capsules, secondary interactions and unusual multi-metallic complexes." Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/9923.
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Research into inorganic supramolecular chemistry is burgeoning, in particular that which focuses on the formation of capsular molecules and the effects that these unique environments have on catalytic reactions. With the aim of producing new ligand designs that could not only support reactive metals, but also partake in supramolecular aggregation to provide a capsular microenvironment, new tripodal ligands and wide span imines and amines have been synthesised. Furthermore, the exploitation of hydrogen-bonding motifs formed through pyrrole-imine tautomerisation upon metallation of these ligands has been explored, with the aim of enhancing reactivity and stabilising reactive intermediates. In Chapter one, the concept of covalent and non-covalent capsules is introduced, and includes the different aspects affecting the encapsulation of molecules and their use as nanoreactors. The use of secondary interactions, e.g. hydrogen-bonding in metal complexes of tetrapodal and tripodal ligands is discussed. Chapter two describes the synthesis of a tripodal pyrrole-imine ligand and the formation of its multi-metallic complexes of Group one metals, transition metal and the f-block elements. The complete and partial tautomerisation of this ligand upon metal complexation is also examined. In Chapter three, the formation of hangman complexes of the tripodal pyrrole-imine ligand is described and is extrapolated to the chemistry of a new pyrrole-amide ligand. The synthesis of this latter ligand and its properties with regards to anion binding are also explored. Chapter four describes the formation of wide span diamine and diimine ligands and their propensity to form adducts with cobalt and zinc chlorometallates and unusual multimetallic palladium complexes. The final conclusions of the work presented in this thesis are drawn in Chapter five. Chapter six presents experimental details and characterising data for all of the new compounds presented in this thesis.
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Saad, Fawaz Ahmed. "Co-ordination chemistry of novel tripodal ligands designed to host anions." Thesis, Cardiff University, 2011. http://orca.cf.ac.uk/55112/.
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The development of novel ligands for the complexation of transition metal ions in inorganic chemistry is a rapidly developing field of study. The broad objective of this work is to design novel tripodal transition metal based receptors of (TPA) frame work which can act as hosts for small molecules (guests) e.g. fluoride and succinate. In addition, investigation into the co-ordination chemistry of those receptors with first row transition metals were explored using variety of characterizing techniques such as: Infrared Spectroscopy (IR), Electronic transitions (UV-Vis), Mass Spectrometry (MS), Nuclear Magnetic Resonance (NMR), Cyclic voltammetry (CV) and Single Crystal Diffractometer (X-Ray). Mono, Bis and Tris thiourea tripodal ligands have been synthesised and their co ordination chemistry has been investigated (chapter 2, 3 and 4) as well as the binding studies of the bisthiourea (chapter 3) to bind: fluoride and succinate using *H NMR titration technique. The co-ordination chemistry of TPPA with some first row transition metals has been studied and it was expected to show high affinity for seven coordination sphere and indeed it has shown strong preference for mono capped octahedral geometry (chapter 5).
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Spencer, Paul. "Polyaza redox-active acyclic and macrocyclic compounds designed to bind cations and anions." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386672.
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Webber, Philip R. A. "Cation and anion recognition by calix[4]arene based ligands." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393989.
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Serpell, Christopher J. "Imidazole-based ligands for anion recognition and catalytic metal nanoparticles." Thesis, University of Oxford, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.533879.
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Lenthall, Joseph T. "Anion and platinum group metal binding of bis(thioureido) ligands." Thesis, Durham University, 2007. http://etheses.dur.ac.uk/2854/.
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A series of bis(thioureido) ligands have been synthesised, which show anion binding in acetone-d(_6). Their structures have been determined by X-ray crystallography and some exhibit hydrogen bonding interactions with the π-electrons of the the thiocarbonyl bond. This hydrogen bonding interaction has been investigated for the general thiocarbonyl and carbonyl bond using the CSD, and a marked difference in the interaction of hydrogen bond donors with the π-electrons of carbonyl and thiocarbonyl bonds has been shown. The bis(thioureido) ligands have been coordinated to platinum group metals and the differing binding modes of the ligands investigated. The reaction of ligands with 2 carbon atoms between thiourea groups with [{Ru(n(^6)-С(_6)Н(_4)МеСН(Ме)(_2))С1(μ- Cl)}(_շ)], yields a mixture of products that may be consolidated into a single product with a water wash. The water instigates a deprotonation of an NH group that allows nitrogen coordination to ruthenium, yielding a S,S,N terdentate Ru(II) half-sandwich complex, with four- and seven-membered adjoining metallacycles. A chiral metal centre is formed and in the solid state, opposite enantiomers hydrogen-bond to each other through chloride counter-ions. Ruthenium complexes with an interaction from the pyridyl nitrogen in ligands containing pyridyl binding moieties have also been characterised. Bidentate S,S coordination is observed for the reaction of bisthiourea ligands with [Pd(dppe)Cl(_2)], forming nine- and ten-membered metallacycles. A similar binding mode is observed in a Pt(II) analogue. A polymer analogue of the bisthiourea ligands has been synthesised, and has been tested to extract metals from mixed metal solutions. Using well-defined metal salts in methanol, ruthenium(II) may be loaded onto the polymer from a single metal solution, acetontrile solvent inhibits the uptake of platinum group metals from mixed metal solutions, the polymer is selective for Cu(II) even when acetonitrile solvent is present and in the absence of Cu(II) or acetonitrile, can selectively extract Pt(II) over Ru(II), Fe(II), Cr(III) and Ni(II). The ruthenium loaded resin may be stripped of Ru(II) effectively using concentrated nitric acid solution in two hours. Testing the bisthiourea polymer in an acetic acid mixed metal solution demonstrated that the polymer was not suitable for platinum group metal extraction from the acetic acid medium, when compared to a commercially available resin.
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Duckmanton, Paul Andrew. "Anion-binding ureaphosphine ligands and their late transition metal complexes." Thesis, University of Nottingham, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.438264.
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Dent, Simon William. "Photo and redox active anion receptors based on transition metal bipyridyl ligands." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361956.
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Schmidlin, Nadja Maria Clara [Verfasser], Tobias [Akademischer Betreuer] Böttcher, and Ingo [Akademischer Betreuer] Krossing. "A novel class of sterically demanding anionic pyridines and its application as a ligand,reducing agent and catalyst." Freiburg : Universität, 2020. http://d-nb.info/1232174165/34.
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Medici, Fabrizio. "Interactions entre les Spirosilane de Martin et Base de Lewis coordination, frustration et nouveau ligand anionique." Thesis, Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLET029.
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Ce travail de thèse est consacré à l’étude de la réactivité du spirosilane de Martin, une molécule présentant des propriétés intéressantes notamment en présence de bases de Lewis, qui a trouvé des applications diverses comme la détection d’ions fluorures. En ce qui nous concerne, nous avons choisi d’étudier l’interaction de ce dérivé du silicium avec des bases de Lewis neutres fortes tels que les Carbènes N-Hétérocycliques (NHC) qui ont été beaucoup utilisés pour stabiliser les espèces de basse valence des éléments du bloc p. Alors que les NHC sont connus pour former avec les chlorosilanes des adduits pentacoordinés stables, aucun exemple avec des silanes non halogénés n’avaient été décrits avant notre étude. Nous avons montré qu’en fonction de l’encombrement stérique des NHC étudiés, ils forment avec le spirosilane de Martin des adduits de Lewis normaux et anormaux stables. Les propriétés « Paires de Lewis Frustrées » (FLP) du spirosilane avec des NHC encombrés ont été examinées ainsi que l’accès à des nouveaux ligands NHC anioniques portant un motif siliconateThis thesis work is focused on the reactivity of Martin’s Spirosilane, a molecule that displays some interesting properties in particular with different Lewis base, founding some interesting application such us fluoride sensor. In our study, we have chosen N-Heterocyclic Carbene (NHC) because they are well known for stabilising low-valence states of p-block elements or for disclosing new reactivities. Besides, NHC are known to form relatively stable adducts with tetravalent halosilanes and also to stabilise silicon(0) species through potassium graphite reductions, but, to the best of our knowledge, no pentacoordinated NHC-adducts with a non-halogenated silane partner has been synthesised to date.The first part of my PhD was focused on the update of Martin’s spirosilane synthesis due to some problem of reproducibility with the known procedure. Once obtained the product, it was begun the investigation of the interaction with different NHC carbene that afforded the corresponding adducts that were fully characterised. The different adducts were then studied as potential Frustrated Lewis Pair and as precursors of anionic-type ligands for the metal's coordination
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Turner, David Roger. "Anion binding properties and solid-state studies of novel urea-containing ligands and derivatives." Thesis, King's College London (University of London), 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415507.
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Naghmouchi, Haithem. "4-t-butylCalix [4] arènes fonctionnalisé avec des groupes d'imidazolium captifs : de nouveaux ligands pour la chimie organométallique et la complexation des anions." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAF069.
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La synthèse de nouveaux calixarènes fonctionnalisés par des groupes d’imidazolium occupe un grand intérêt qui se justifie par la facilité de fonctionnalisation des atomes d’azote de l’imidazole d’une part et d’autre part, par les propriétés de reconnaissance anionique liée à la charge positive délocalisée.Au cours de la première étape, nous avons effectué la fonctionnalisation des calixarènes au niveau de la partie basse en gardant le t-butyle au niveau de la partie haute. Dans un second temps, nous avons réalisé une substitution des atomes de brome par des dérivés d’imidazoles tel que 1-méthylimidazole, 2,4,6-triméthlimidazole, 2,6-diisopropylimidazole, l’imidazole et le benzimidazole afin de créer des ligands imidazolium, par la suite une réaction des sels d’imidazolium avec le nickelocène a conduit à la formation des complexes du NiCp. Dans une dernière étape, nous avons déterminé les propriétés complexantes des dérivés d’imidazolium vis-à-vis des anions organiques et inorganiquesThe synthesis of new calixarenes functionalized with groups imidazolium occupies a large interest, which is justified by the ease of functionalization of the nitrogen atoms of the imidazole on the one hand and on the other hand, by the anionic recognition properties related the delocalized positive charge.During the first step, we conducted the functionalisation of calixarenes at the lower part bearing the t-butyl at the top. Secondly, we made a substitution of bromine atoms by imidazole derivatives such as 1-methylimidazole, 2,4,6-triméthlimidazole, 2.6-diisopropylimidazole, imidazole and benzimidazole to create imidazolium ligands, subsequently a reaction imidazolium salts with nickelocene led to the formation of complexes NiCp.In a last step, we determined the complexing properties of imidazolium derivatives vis-à-vis organic and inorganic anions
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Higginson, Joshua J. "Synthesis and coordination chemistry of ditopic ligands capable of coordinating metal ions and interacting with anions." Thesis, University of Huddersfield, 2015. http://eprints.hud.ac.uk/id/eprint/26444/.
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The aim of this research was to synthesise a series of novel organic multidentate ligands which contain N-donor domains for the coordination of metal ions and amide or amine hydrogen atoms which are capable of interaction with anions. It was envisaged that incorporation of these two binding units would produce a system where the metal ions would control the ability of the ligand to interact with anions or vice versa. Ligand 1 contains a tetradentate N-donor domain formed by a central bipyridine, two thaizole units and two amide units attached in the 4,4’-position of the bipyridine unit. Reaction of this with divalent metal ions results in a mono-nuclear complex where the metal is bound by the N-donor atoms and the amides interact with a variety of anions. Reaction with monovalent metal ions results in the formation of a dinuclear double helicate with the metal again coordinated by the N-donor domains and the anions interacting with the amide hydrogen atoms. This results in a polymeric assembly in the solid state. Ligand 2 contains an identical tetradentate domain comprised of the same N-donor units; however the single amides in the 4,4’-position have been removed and a diamide attached in the 3,3’-position of the bipyridine unit. Reaction of [L2 with divalent cations results in a similar mono-nuclear species. The metal centre is coordinated by the N-donor atoms and one of the acetyl units from two adjoining ligands with the counter ions undergoing interactions with the diamide hydrogen atoms. Coordination of the same ligand with a monovalent cation resulted in a di-nuclear double helicate, each metal centre is fulfilled by the N-donor atoms of the ligand strand and the hydrogen atoms of the diamide units interact with anions. This too results in a polymeric assembly in the solid state. Ligands 3 and 4 contain the iso-structural tetradentate N-donor domain seen in [L1] and [L2] but their functionality in the 3,3’-position differ. Ligand 3 contains a urea group while ligand 4 has a single amide group attatched to an indole unit. Coordination of [L3] and a divalent metal ion results in the formation of a mono-nuclear species with the metal ion bound by the central bipyridine and the N-donor of two thaizole units. Furthermore each of the urea groups in the 3,3’-position undergo favourable interactions with the perchlorate counter ions. A solid state structure of Ligand 4 was only successful with a monovalent cation resulting in the formation of a dinuclear double stranded species. Each metal centre exhibits a distorted trigonal planar geometry through coordination with a pyridine and thiazole ring of one strand and a single thiazole ring of another. The indole and amide of each ligand strand undergo two sets of interactions; anion interactions through the amide and indole hydrogen atoms as well as complementary intermolecular interactions between the indole N···H units of one ligand and the carbonyl C···O units of another complex. Both [L3] and [L4] exhibit long range order through favourable anion-NH interactions however [L4] also displays complimentary indole/acetyl interactions to develop a larger aggregate species. In all these cases the resultant complex is independent upon which anion is used. However, this is not the case with ligand 5. Reaction of [L5] with Cu(BF4)2 or Cu(ClO4)2 gave a dinuclear double helicate with a cleft within the helicate assembly in which an anion is bound. However, reaction of this with half an equivalent of either sulphate (SO4 2-) or dihydrogen phosphate (H2PO4 -) results in the formation of a different dinuclear double helicate whereby the cleft is occupied by either a dihydrogen phosphate or sulphate anion which bridges the metal centres. Further addition of sulphate results in no change of the ESI-MS indicating the dinuclear double helicate persist however addition of one equivalent of di-hydrogen phosphate leads to the formation of a pentanuclear circular helicate. Each metal centre is coordinated by the pyridine and thiazole units of two different ligand strands and a single Cu···O interaction from one of the dihydrogen phosphates. The inclusion of three dihydrogen phosphates into the centre of the assembly as well as a series of phosphate-ligand and phosphate-phosphate interactions leads to the dimerization of the structure with another set of phosphates from a second assembly. Further reaction of this dinuclear species with one equivalent of (Bu4N)NO3 resulted in the formation of a hexanuclear circular meso-helicate (or mesocate). In this structure each Ndonor domain of a thiazole and pyridine ring coordinate two different Cu2+ metal centres. Each metal centre exhibits a distorted octahedral arrangement with two ligand strands completing 4 of its 6 coordination sites, the remaining sites are occupied by two O-donors of a nitrate anion. In addition an amine of each ligand strand points into the centre of the complex creating a cavity capable of hosting two nitrate anions. Ligand 6 is made up of the same bis-bidentate donors as ligand 5 with the addition of a nitrogen atom into the central phenyl spacer. On reaction of [L6] with a divalent metal ion (e.g. Cu(II)) a simple mono-nuclear structure is observed. Although a mono-nuclear assembly is expected, it is interesting that even a simple change in the ligand strand can have a dramatic affect on the self-assembly process. When a central 1,3-phenylene spacer is employed (i.e. [L5]) a dinuclear double helicate is formed, however, when a 1,3-pyridine unit is contained within the ligand strand (i.e. [L6]) a simple mono-nuclear species is produced.
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Pomećko, Radosław. "Phosphonium and ammonium calix[4]arenes : synthesis and anion-ligand interaction studies." Université Louis Pasteur (Strasbourg) (1971-2008), 2007. https://publication-theses.unistra.fr/public/theses_doctorat/2007/POMECKO_Radoslaw_2007.pdf.
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Ces travaux de thèse portent sur des dérivés des calix[4]arènes porteurs de fonctions chargées positivement, des phosphoniums et des ammoniums. Il comporte quatre chapitres. Le premier expose les propriétés particulières des anions et fait le point sur des données bibliographiques concernant leurs interactions avec des ligands acycliques (chélands et podands) et macrocycliques (coronands, cryptands, porphyrines, calixarènes,…). Le second rapporte la synthèse et la caractérisation des nouveaux composés obtenus et détaille la partie expérimentale. Le troisième chapitre présente l’étude des interactions entre ces ligands et une grande variété d’anions (I-, NO3 -, SCN-, ClO4 -, SO4 2-, S2O3 2-, CrO4 2-, MoO4 2-, Cr2O7 2-) en solution en utilisant différentes techniques, la RMN du proton et du phosphore 31 dans le chloroforme et l’acétonitrile, la spectrophotométrie UV-VIS dans le méthanol et l’acétonitrile, la microcalorimétrie et l’extraction liquide-liquide. Le quatrième chapitre est consacré à l’application de ces ligands dans des électrodes sélectives à membranes (ISE). .Aniony odgrywają znaczącą rolę w procesach biologicznych i chemicznych. Wykorzystywane są w wielu gałęziach przemysłu: galwanotechnice, przemyśle tworzyw sztucznych, wytwarzaniu nawozów sztucznych czy środków pirotechnicznych. Ma to odzwierciedlenie we wzrastającym zanieczyszczeniu środowiska takimi substancjami, które nierzadko trudne są do oznaczenia i oddzielenia. Nadmiar fosforanów i azotanów w ściekach wywoływać może eutrofizację w zbiornikach wodnych. Zaburzenia równowagi chlorkowej w komórce wywołują groźne choroby. Nadchlorany które prócz dużej rozpuszczalności w wodzie rozpuszczają się również w tłuszczach mają zdolność do kumulowania się w organizmie. Ich obecność powoduje zaburzenia wzrostu oraz obniżenie czynności tarczycy ze względu na ich duże podobieństwo do anionu jodkowego. Dlatego możliwość dokładnego, selektywnego oznaczania stężeń anionów w różnorakich próbkach jest tak bardzo ważne. Szczególne właściwości anionów, takie jak: zróżnicowana geometria jonów, rozmiary znacznie większe od rozmiarów kationów, mały ładunek w stosunku do promienia, możliwość zmiany stopnia utlenienia atomu centralnego anionu, zróżnicowana kwasowość hydrolizujących soli większości anionów sprawia, że projektowanie receptorów anionów stanowi dla chemika duże wyzwanie. Celem badań była synteza ligandów selektywnych na aniony, charakteryzujących się wysoką lipofilowością, i ich zastosowanie jako materiału aktywnego w czujnikach chemicznych, membranowych elektrodach jonoselektywnych. Celem było również poznanie istoty oddziaływań pomiędzy anionami a badanymi ligandami. Praca polegała na projektowaniu i syntezie nowych związków o właściwościach jonoforowych, opartych na szkielecie p-tertbutylokaliks[4]arenu i zawierających naładowane grupy amoniowe lub fosfoniowe. Praca zredagowana jest w formie 4 rozdziałów poprzedzonych krótkim wstępem. W pierwszym rozdziale zaprezentowano szczególne właściwości anionów, które sprawiają, że projektowanie receptorów anionów stanowi dla chemika duże wyzwanie. W I części usystematyzowane zostały rodzaje oddziaływań między ligandami a anionami. Przedstawiono w nim również przykłady ligandów oddziałujących z anionami, zebrane na podstawie najnowszej literatury. Cześć druga pracy przedstawia dokładny opis syntez amoniowych i fosfonowych pochodnych p-tert-butylokaliks[4]arenu oraz substratów do ich syntezy (związki S, S1 – S6). Syntezowano cztery amoniowe pochodne kaliks[4]arenu (związki 1 – 4) oraz jedenaście pochodnych fosfonowych ( 5 – 8 oraz 5a, 6a, 6b, 7a, 8a, 8b, 10) różniących się między sobą zarówno rodzajem grupy osfoniowej jak i rodzajem przeciwjonu. Związki fosfoniowe oparte na strukturze kaliks[4]arenu nie były dotychczas syntezowane. By zbadać wpływ preorganizowanej struktury kaliks[4]arenu na właściwości kompleksujące badanych ligandów syntezowano monomer 0 zawierający jedną grupę trifenylofosfoniową. Budowę wszystkich związków potwierdzono spektroskopią 1H NMR oraz 31P NMR, spektrometrią mas i analizą elementarną. .
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Wenzel, Marco. "Tripodale Azaliganden - Ambivalente Rezeptoren für Kationen und Anionen." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1210087455514-66575.
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Das Ziel der vorliegenden Arbeit bestand in der Synthese von neuen funktionalisierten tripodalen Azaliganden auf Basis von Tris(2-aminoethyl)amin (Tren) und ihrer Charakterisierung als Rezeptoren und Extraktionsmittel für Kationen, Anionen sowie Salze. Die Komplexbildungs- und Phasentransfereigenschaften gegenüber den Kationen Ag(I), Co(II), Ni(II), Cu(II), Zn(II) und Cd(II) sowie den Anionen Cl-, Br-, I-, H2PO4-, SO42- und HCrO4- wurden durch Flüssig-Flüssig-Extraktion und Flüssigmembrantransport, 1H-NMR-Spektroskopie sowie Silberpotentiometrie untersucht; Struktur-Wirkungsbeziehungen für die jeweiligen Wirt/Gast-Systeme wurden abgeleitet. Röntgenkristallstrukturanalysen ausgewählter Komplexe mit den Kationen Ag(I), Ni(II) und Cu(II), den Anionen Br- und BF4- sowie dem Salz Hg(ClO4)2 ergänzten die gewonnenen Aussagen durch detaillierte Informationen zur Struktur und zu den auftretenden Wechselwirkungen. In die Betrachtungen wurden vergleichende Untersuchungen zur Ag(I)-Bindung durch strukturverwandte tripodale Schiffsche Basen einbezogen. Zusammenfassend wird der Einfluss der unterschiedlichen ligandspezifischen Charakteristika sowie der Substratspezies auf die Komplexbildung in Lösung und die Festkörperstruktur diskutiert. Die untersuchten tripodalen Aminverbindungen auf Basis von Tren zeigten in Abhängigkeit von ihrer Struktur ein differenziertes Extraktionsverhalten im System Metallsalz-Puffer-Wasser/Ligand-Chloroform. Als wesentliche Einflussfaktoren auf die Extraktion erwiesen sich Art, Anzahl und Anordnung der Donoratome sowie die differenzierte Lipophilie der Liganden. Die Zusammensetzung der extrahierten Komplexe in der organischen Phase ergab sich in den meisten Fällen zu 1:1 (Ag(I) : Ligand). Die bestimmte Reihe steigender Komplexstabilität für die 1:1-Komplexe von Ag(I) in Methanol unterstreicht in Analogie zu den Extraktionsuntersuchungen den Einfluss der Ligandcharakteristika auf die Komplexbildung. So führten Liganden mit tertiären Aminstickstoffatomen, zusätzlichen O-Donoratomen sowie sterisch anspruchsvollen Substituenten im Molekül zu geringeren Komplexstabilitäten, während zusätzliche S- und Pyridin-N-Donoratome in den untersuchten Aminverbindungen eine deutliche Steigerung der bestimmten Konstanten ergaben. Vergleichende Untersuchungen mit tripodalen Iminopodanden zeigten mit Ausnahme des 2-pyridylmethyl-substituierten Liganden generell niedrigere Stabilitäten der Ag(I)-Komplexe. 1H-NMR-Untersuchungen zur Komplexbildung in Lösung deuten unter veränderten Bedingungen auch auf einen möglichen Wechsel in der Komplexzusammensetzung und im Bindungsmuster für Ag(I) in Abhängigkeit von den im Molekül vorhandenen Donorfunktionen hin. Während für N4-Liganden ohne zusätzliche Donoratome sowie in Anwesenheit von S- und N-Donoratomen eine Zusammensetzung (Ag(I) : Ligand) von 1:1 bestimmt wurde, führen zusätzliche Pyridin-N-Donoratome zu einem stöchiometrischen Verhältnis von 3:2. Die Röntgenstrukturanalysen der Ag(I)-Komplexe von tripodalen Schiffschen Basen mit unterschiedlichen Substituenten unterstreichen die Variabilität der Koordinationsgeometrie von Ag(I) in Abhängigkeit vom Liganden. Interessant ist die Ausbildung von schwachen C-H···Ag-Wasserstoffbrücken in den Ag(I)-Komplexen der benzyl- und 4-biphenylmethyl-substituierten Liganden. Für die Kationen Co(II) und Zn(II) wurden mit den untersuchten Liganden generell nur geringe Extrahierbarkeiten erzielt. Dabei ist der Einfluss von Ligandstruktur sowie Lipophilie der Verbindungen auf die Extraktion stärker ausgeprägt als für Ag(I). Die Extraktion aus einem Gemisch von Co(II), Ni(II), Cu(II), Zn(II) und Cd(II) zeigte generell einen Anstieg der Extraktion in der Reihe Co(II) < Ni(II) < Zn(II) < Cd(II) < Cu(II). Lediglich die Verbindung mit einer OH-Funktion in 2-Position der aromatischen Substituenten führte zu höheren Extraktionsausbeuten für Co(II), Ni(II) und Cd(II) gegenüber Cu(II) und Zn(II). Röntgenstrukturanalysen von vier Cu(II)- bzw. Ni(II)-Komplexen veranschaulichen die bevorzugte höhere Koordinationszahl dieser Metallionen in relevanten Komplexen im Vergleich zu Ag(I). Die höhere Koordinationszahl wird dabei durch eine zusätzliche Koordination von Anionen oder Lösungsmittelmolekülen erreicht. Im Gegensatz zu den Kationen ist die Anionenextraktion wesentlich sensitiver gegenüber wechselnden experimentellen Bedingungen. Das hängt insbesondere mit den veränderten Bindungsverhältnissen in Anionenkomplexen zusammen. So wird die Extraktionsausbeute stark durch die Lipophilie der Liganden beeinflusst; ein signifikanter Anionentransport in die organische Phase wurde lediglich mit lipophilen Liganden erzielt. Die beobachtete Abstufung steigender Extraktion SO42- < Cl- < HCrO4- < I- ist in Übereinstimmung mit der zunehmenden Lipophilie dieser Anionen. In Abhängigkeit von der Natur der vorhandenen N-Donorfunktionen im Liganden und der Struktur der Liganden insgesamt wurde ein ausgeprägter pH-Einfluss auf die Extraktion der Anionen beobachtet. Während für die Liganden mit sekundären Aminfunktionen hohe Extrahierbarkeiten bei einem pH-Wert von ca. 5 auftraten, stiegen die Extraktionsausbeuten für Verbindungen mit tertiären Aminstickstofffunktionen mit abnehmenden pH-Wert kontinuierlich an. Die untersuchten Anionen wurden vorwiegend unter Bildung von 1:1- und 1:2-Komplexen (Anion : Ligand) in die organische Phase überführt. Für den Membrantransport war eine steigende Transportrate entsprechend der Dominanz der Lipophilie in der Reihe H2PO4- < SO42- < Cl- < Br- charakteristisch. Ein bevorzugter Transport von Cl- gegenüber Br- wurde hingegen mit sterisch anspruchsvollen Liganden sowie ausgeprägt lipophilen Verbindungen erreicht. Die Strukturen von zwei Anionenkomplexen mit BF4- bzw. Br- zeigen differenzierte Bindungsmuster. Einmal verhindern in einem Iminopodanden starke intramolekulare Wasserstoffbrücken zwischen dem protonierten Brückenstickstoff und den Iminfunktionen der Podandarme einen Einschluss des BF4--Anions in den vorliegenden Pseudokäfig, so dass die Koordination des Anions lediglich über schwache C-H···F-Kontakte an der Ligandperipherie erfolgt. Im Gegensatz dazu sind in einem N4-Aminliganden die drei Aminfunktionen der Podandarme protoniert. Die Br--Ionen werden sowohl durch ladungsunterstützte N-H···Br- als auch durch C-H···Br-Wasserstoffbrücken vom Liganden koordiniert. Weiterhin konnte in der Arbeit der Nachweis geführt werden, dass durch die Kombination von kationen- und anionenbindenden Funktionseinheiten in einem tripodalen Liganden die simultane Bindung und Extraktion von Kationen und Anionen möglich wird. Die Röntgenkristallstruktur eines Hg(ClO4)2-Komplexes bestätigt dabei die gleichzeitige Koordination von Kation und Anion durch die unterschiedlichen spezifischen Funktionseinheiten im Molekül.
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Rivomanana-Rabesandratana, Soa. "Activité et transformation des alcynes sur des clusters du ruthénium dopés par des anions nucléophiles." Toulouse 3, 1992. http://www.theses.fr/1992TOU30107.
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La these presentee ici propose une rationalisation de la synthese des clusters alcyne/ruthenium destinee a ouvrir la voie au developpement de la chimie de ces composes. Le principe est le suivant: en dopant le cluster ru#3(co)#1#2 par addition d'un promoteur halogene, le sel ppncl utilise en milieu aprotique, ppn=cation bis-(triphenylphosphine)iminium) on obtient des complexes anioniques actives de formule ppnru#3(co)#1#2##ncl dans lesquels le ligand cl# exerce un effet labilisant sur les groupements carbonyle. Ces complexes reagissent en quelques minutes avec les alcynes les plus divers a temperature ambiante pour donner une seule espece activee, de formule ppnru#3(-cl)(-rccr)(co)#9. Cet intermediaire est utilise pour synthetiser les principaux complexes qu'il est theoriquement possible d'envisager a partir d'un alcyne et de trois centres de ruthenium, et en particulier, ru#3(-h)#2(-rccr)(co)#9, ppnru#3(-h)(-rccr)(co)#9, ru#3(-h)(-rccr)(co)#9, ru#3(-rccr)(co)#1#0, ru#3(-rccr)#2(co)#8. La reaction de l'espece activee ppnru#3(-cl)(-rccr)(co)#9 avec le bis(diphenylphosphino)methane permet d'isoler le complexe ru#3(-rccr)(-dppm)(co)#7, premier complexe du ruthenium electroniquement insature possedant un alcyne coordonne au mode perpendiculaire. Ce complexe reagit rapidement a 25c avec divers ligands donneurs, soit, co, h#2, dppm, pour donner respectivement les nouveaux complexes ru#3(-rccr)(-dppm)(co)#8, ru#3(-h)#2(-rccr)(-dppm)(co)#7, et ru#3(-rccr)(-dppm)#2(co)#6. Il reagit egalement avec le phenylacetylene pour donner le nouveau complexe ru#3(-hccph-c(o)-phccph)(-dppm)(co)#6 comprenant le fragment cetonique coordonne hccph-c(o)-phccph resultant du couplage des deux alcynes et d'un co. Ce complexe modelise ainsi la formation d'une cetone, assistee par plusieurs centres metalliques
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Amawi, Rema Mouawya Klausmeyer Kevin Kenneth. "Synthesis and characterization of silver(I) salts with amino methyl pyridines containing phosphines novel complex formation upon ratio, anion, or ligand changes /." Waco, Tex. : Baylor University, 2008. http://hdl.handle.net/2104/5180.
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Brennessel, William W. "Low valent iron and cobalt chemistry naphthalene and anthracene as radical anion reducing agents and labile ligands /." Diss., Click on "Connect to Digital Dissertations", 2009. http://www.lib.umn.edu/articles/proquest.phtml.
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Turkington, Jennifer Rachel. "Investigation into the modes of action of extractants for base metal cations and metalate anions." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/9567.
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This thesis involves the design and development of reagents for the recovery of base metals (specifically zinc, nickel and cobalt) in hydrometallurgical solvent extraction processes. The work aims to demonstrate how ligand design can affectively tune the strength and selectivity of extractants to achieve efficient recovery of the desired base metals. Chapter 1 reviews current solvent extraction processes used in extractive metallurgy, encompassing both the well established technologies developed for sulfate streams as well as those more recently explored for treating chloride streams. Also reviewed, is the nature of the chemical binding involved in the three key modes of extraction; namely cation transport, anion transport and metal salt transport. Chapter 2 summarises the methodologies that have been established during this research for the appropriate testing of these reagents. Chapter 3 deals exclusively with the processing of zinc sulfide ores with an aim to design reagents to achieve concentration and separation of zinc in chloride hydrometallurgical circuits. The amido functionalised reagents that are reported have a common structural feature with ligands that have been previously studied by the Tasker group (Ross J. Ellis Thesis, University of Edinburgh, 2009). A six membered chelate ring is formed by a protonated amino nitrogen atom and an amido oxygen atom in a sequence of the type R2HN+-CH2-NR-CO-R. This differs from those previously studied which have a sequence of the type R2HN+-CH2-CHR-CO-NR2. The pro-ligands (L) operate via an anion exchange mechanism (Equation 1) whereby two protonated ligands (LH+) coordinate to the outersphere of anionic zinc(II) or iron(III) chloridometalates from acid chloride solutions using both N-H and C-H hydrogen-bond donors. pH dependent solvent extraction experiments have concluded that this reagent series achieves zinc(II) loading with pH0.5 values that are competitive with the previous ligand series (Ross J. Ellis Thesis, University of Edinburgh, 2009). Chloride concentration dependent solvent extraction experiments have demonstrated that the reagents show an unusually good selectivity for ZnCl4 2- over chloride or FeCl4 - in equilibrium of the type; yLorg + yH+ +MClx y- ⇌ [(LH)yMClx](org) (1) The development of bidentate and tridentate pyrazolone-based pro-ligands for the extraction of nickel and cobalt from mixed metal sulfate streams is considered in Chapters 4 and 5. These reagents (LH) operate via metal cation transport, where an inner-sphere complex of nickel(II) or cobalt(II) is formed with the ligand (L-) see Equation 2. A combination of N, O and S donors has been incorporated into 1-phenyl-3-methyl-4- acylpyrazol-5-ones and their respective 4-acylpyrazolone oximes in order to tune the bidentate ligands (L-) for optimal coordination with nickel(II) or cobalt(II). Substituent effects have also been investigated, by synthesising a series of 1-(2-X-phenyl)-3-methyl-4- acylpyrazol-5-one oximes [X = Cl, H]. Substitution in the 3-position of the phenol group in phenolic oximes has been reported to increase extractant strength for copper by two orders of magnitude (Ross S. Forgan Thesis, University of Edinburgh, 2008). Similar improvements were not observed in this study. The nature of this effect has been attributed to buttressing of hydrogen-bonds, where the substituent forms a stabilising, bifurcated hydrogen-bond between the oximic hydrogen and the pyrazolonic oxygen. yLHorg + My+ ⇌ [(L)yM]org + yH+ (2) Tridentate analogues of the oxime reagents above have been prepared as imines derived from anilines contained o-O, S or N donor atoms. It was hoped that these would give high spin octahedral nickel(II) complexes in extraction processes. They proved to be weak extractants. Chapter 6 focuses of the development of bidentate pyrazolethiones for the selective extraction of cobalt from manganese in acidic sulfate streams. These reagents have been designed to favour coordination to metals in a tetrahedral geometry as shown by L. Emeleus and A. Smith for copper and zinc (Lucy Emeleus Thesis, University of Edinburgh 1999 and Andrew Smith Thesis, University of Edinburgh 2000).
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Cortadellas, Olivier. "Complexes métalliques à ligands pseudo-oxocarbone cyanamido-squarate : vers des propriétés électrochromiques et photovoltai͏̈ques." Toulouse 3, 2004. http://www.theses.fr/2004TOU30035.
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Les dianions n-NCNsq2- (n = 4 ; 3,4 ; 2,4) sont des dérivés du dianion squarate pour lesquels des fonctions carbonyle sont substituées par une ou deux fonctions cyanamido NCN. L'étude électrochimique de ces composés a montré une oxydation en deux étapes monoélectroniques successives permettant l'obtention de radicaux-anions n-NCNsq-· stables à basse température dans l'acétonitrile et d'espèces neutres n-NCNsq instables. Ce comportement électrochimique associé à des colorations différentes en fonction du degré d'oxydation confère à ces composés des propriétés électrochromiques. Les études structurales réalisées sur ces dianions ont également permis de mettre en évidence la planéité et l'aromaticité de ces molécules. Une fois la caractérisation des dianions cyanamido squarate terminée, nous nous sommes intéressés aux propriétés complexantes de ces molécules vis-à-vis du nickel(II), du palladium(II) et du cuivre(I) et (II). La détermination structurale de dix complexes a montré l'existence de plusieurs modes de coordination par les atomes d'azote : nitrile, amido ou encore nitrile-amido. Les études électrochimiques réalisées sur les complexes synthétisés ont permis de mettre en évidence des processus d'oxydation qui diffèrent selon le métal. Si les complexes du Ni(II) se dissocient au cours de nos études, les complexes du Pd(II), du Cu(I) et du Cu(II) présentent une certaine stabilité et un comportement électrochimique semblable à celui observé pour les dianions n-NCNsq2-. .The n-NCNsq2- dianions derive from squarate dianions, which carbonyl functions have been substituted by one or two cyanamido NCN functions. The electrochemical study of these compounds has shown an oxydation process following two successive mono-electronic steps giving stable radical-anions n-NCNsq-· at low temperature in acetonitrile and then unstable neutral species. These electrochemical behavior associated with a color change depending on the oxidation state give to these compounds electrochromic properties. The structural studies of these dianions have evidenced the planarity and aromaticity of these molecules. After the caracterization of the cyanamido squarate dianions, we have been interested in the dianions complexing properties with nickel(II), palladium(II) and copper(I) and (II). .
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Engle, Keary Mark. "Ligand-accelerated catalysis in palladium(II)-mediated C-H functionalisation ; Hydrogen bonding effects on the reactivity of fluoride anion." Thesis, University of Oxford, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.711664.
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Nguyen, Thi Hong Long. "Pinces moléculaires photo-isomérisables pour l’étude des changements allostériques des récepteurs pentamériques canaux." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS395/document.
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Résumé : Au cours de ce travail, nous avons effectué une étude méthodologique concernant la synthèse d'azobenzènes tétrasubstitués en position ortho pour mieux comprendre les éléments affectant leurs synthèses, généralement inefficaces, et afin d'en améliorer les rendements. Nous avons conclu que l'inefficacité de cette synthèse est causée par des effets stéréoélectroniques : l’effet stérique du substituant en position ortho, qui s’ajoute à l’effet électronique du groupement en position para. Après différentes optimisations, nous avons réussi à synthétiser un azobenzène tétrachloré et un azobenzène tétrafluoré via un intermédiaire nitrosobenzène avec de bons rendements.Le dérivé tétrafluoro azobenzène a été ensuite fonctionnalisé en introduisant une chaîne alcyne terminée par un groupement maléimide afin de permettre sa fixation sur un résidu cystéine. Les propriétés physicochimiques très intéressantes (lumière verte d'irradiation,T1/2 = 72 jours, photostable) de cette pince ont été évaluées.Parallèlement, une synthèse efficace et pratique pour générer directement la fonction hydroxyle en ortho de l'azobenzène dans des conditions douces a été développée. Nous avons synthétisé plusieurs séries en faisant varier les substituants enpositions para ou/et en ortho afin d'étudier l'influence de ces subsituants sur la régiosélectivité de cette ortho-hydroxylation. L'équation de Jaffé et ses extensions ont donné une relation linéaire avec d'excellents coefficients de détermination R2.Enfin, les azophenols ont été évalués comme des détecteurs colorimétriques d'anions. Leurs caractéristiques ainsi que le mécanisme d'interaction ont été déterminés par une inspection visuelle, des mesures UV-Visible et des expériences de RMNAbstract : A methodological study on the synthesis of tetrasubstituted azobenzenes has been realized. We concluded that synthesis of multisubstitued azobenzene is hardly affected by the steric hindrance in ortho position and the electronic effect of para substituents.A tetrachloro and a tetrafluoro azobenzene have been synthesized in good yields, via nitrosobenzene intermediate. The tetrafluoro derivative was then functionalized with an alkyne chain containing a maleimide group for bioconjugation to cysteine residue. Its interesting photoisomerisation properties (green light of irradiation,1/2 = 72 days, photostable) were evaluated.We also developed a practical and effective method for direct ortho-hydroxylation of azobenzenes under mild conditions. The reaction showed a very good functional groups tolerance, leading to a wide range of original azophenols in satisfying to high yields.Through Hammett-Jaffé analyses, we presented a study that correlated electronic and steric perturbations induced by substituents nature to the regioselectivity of this direct hydroxylation process.Azophenols were finally evaluated as anion sensors. Anion sensing characteristics as well as interaction mechnism were determined using visual inspection, UV-Vis and NMR spectrocopy
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Copey, Laurent. "Synthèses et applications de nouveaux ligands pyrroliques et méthodologies de synthèse de phosphines P-chirogéniques." Thesis, Lyon 1, 2014. http://www.theses.fr/2014LYO10259/document.
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Deux thématiques principales ont été étudiées au cours de cette thèse. La première partie porte sur la synthèse de complexes de manganèse dérivés de porphyrines et de salens. L'activité catalytique de ces complexes a été évaluée dans l'époxydation d'alcènes non-Fonctionnalisés. Suite à cette étude, les propriétés électroniques des ligands ont été étudiées, notamment par le biais de la complexation d'anions. Dans une deuxième étape, nous nous sommes intéressés à la synthèse de phosphines P-Chirogéniques. Afin de trouver un substitut à l'éphédrine, couramment utilisée dans ces synthèses, des dérivés du (1S,2S)-2-Aminocyclohexanol et de la D-Glucosamine ont été synthétisés. L'utilisation de groupements sulfonamides a permis l'obtention aisée d'oxazaphospholidines N-Tosylées. L'un ou l'autre diastéréoisomère de cet hétérocycle peut être obtenu en fonction du degré d'oxydation du réactif phosphoré utilisé. Avec cette stratégie, divers oxydes de phosphines ont été obtenus avec de bons rendements et de bonnes énantiosélectivitésThis thesis is divided in two parts. The first part focuses on the synthesis of manganese complexes derived from porphyrins and salens. The catalytic activity of these complexes were evaluated toward the epoxidation of unfunctionalized alkenes. Next, the electronic properties of the ligands were evaluated using their anion binding properties. In a second part, we were interested in the synthesis of P-Chirogenic phosphines. In order to find a surrogate to ephedrine, that is commonly used in those syntheses, derivatives from (1S,2S)-2-Aminocyclohexanol and D-Glucosamine were synthesized. The use of sulfonamides allows the access to N-Tosylated oxazaphospholidines. Both diastereoisomers could be synthesized depending on the oxydation state of the phosphine precursor. Using this strategy, various phosphine oxides were obtained in good yields and enantioselectivities
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Schulte, Thorben Rüdiger. "Metal- and Ligand-Centered Chirality in Square-Planar Coordination Compounds." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://hdl.handle.net/21.11130/00-1735-0000-0005-126A-0.
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Abramov, Vladislav [Verfasser], and Gerd [Akademischer Betreuer] Meyer. "New Nickel(II) Complexes with N-donor Ligands and Anions as Coligands : Structures and Optical Properties / Vladislav Abramov. Gutachter: Gerd Meyer." Köln : Universitäts- und Stadtbibliothek Köln, 2011. http://d-nb.info/1038111986/34.
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Tong, Lianpeng. "Mononuclear Ruthenium Complexes that Catalyze Water to Dioxgen Oxidation." Doctoral thesis, KTH, Organisk kemi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-104765.
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The theme of this thesis is the development of mononuclear Ru-based complexes that are capable of catalyzing the water oxidation (or O2-evolving) reaction, e.g. 2 H2O → O2 + 4 H+ + 4 e−. Several families of mononuclear Ru water oxidation catalysts were designed and prepared. They feature with anionic ancillary ligands that contain carboxylate or phenolate donors. The properties of the catalysts were investigated in various aspects including coordination geometry, electrochemical behavior, and ligand exchange. All catalysts showed outstanding catalytic activity towards water oxidation in the presence of cerium(IV) ammonium nitrate as a sacrificial oxidant. High-valent Ru intermediates involved in the reactions were characterized both experimentally and theoretically. The kinetics of catalytic water oxidation was examined based on one catalyst and a prevailing catalytic pathway was proposed. The catalytic cycle involved a sequence of oxidation steps from RuII−OH2 to RuV=O species and O−O bond formation via water-nucleophilic-attack to the RuV=O intermediate. By comparing properties and catalytic performance of Ru catalysts herein with that of previously reported examples, the effect of anionic ancillary ligands was clearly elucidated in the context of catalytic water oxidation. Aiming to further application in an envisaged artificial photosynthesis device, visible light-driven water oxidation was conducted and achieved primarily in a homogeneous three-component system containing catalyst, photosensitizer, and sacrificial electron acceptor. Moreover, one model Ru catalyst was successfully immobilized on ordinary glass carbon surface through a facile and widely applicable method.QC 20121112