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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Star Shaped Thieno- and Thienylaryls as Multifunctional Materials

Robertson, Sean January 2015 (has links)
The work in this thesis was undertaken to explore both the effect of heteroatoms on the semiconducting properties of star-shaped thienoacenes, and to expand the scope of these materials to fields outside of organic semiconductors. Overall, new star-shaped molecules were prepared with a view towards applications such as thin film transistors, as the organic linker component in metal-organic frameworks, and as ligands that could coordinate to transition metals through the sulfur atom. The first chapter describes the properties of star-shaped molecules, the theory underlying their semiconducting behaviour, and the previous work that motivated the research contained herein. The second chapter of this thesis outlines the synthetic methodology that was utilized to achieve the molecular targets, as well as the characterization techniques that are used to reveal the properties of organic semiconductors. The third chapter of this thesis describes the synthesis and optoelectronic properties of novel nitrogen-containing semiconductor molecules called thienoacridines, and their comparison to carbon-and-sulfur based analogues, thienoanthracenes. The fourth and fifth chapters concern the synthesis of functionalized star shaped thienylbenzene molecules. In Chapter 4, these molecules are decorated with carboxylic acid groups so that they may act as tetrapodal MOF linkers. In Chapter 5, they are equipped with N-aryl(azomethine)thiophene moieties to explore sulfur coordination and act as ligands. The sixth chapter provides conclusion to this work, and possible future directions of the research conducted herein.
12

Cálculos ab initio para investigação de propriedades eletrônicas e espectroscópicas de complexos de epiisopiloturina com Cu e Zn / Ab Initio Calculations for Investigation of Spectroscopic and Electronic Properties of Complexes of Epiisopiloturine with Cu and Zn

Virgino, Adamor Luz Eleiel 29 September 2017 (has links)
O entendimento das propriedades de complexos metálicos é de fundamental importância para o desenvolvimento de fármacos. No entanto, tanto do ponto de vista experimental quanto no de modelagem teórica, ainda temos muitas dificuldades de simular e mensurar as mudanças que a complexação com um metal causa em um composto. Este trabalho apresenta estudos de simulacões ab initio de complexos de Epiisopiloturina com Cu e Zn. Foram realizadas otimizações de estrutura, simulaçoes de espectroscopia vibracional, NMR e EPR além de estudos de reatividade. Obtivemos uma geometria otimizada condizente com a da forma cristalizada. Além disso, os resultados espectroscópicos mostram que as estruturas dos com plexos permanecem intactas em solução. Por fim, os estudos de reatividade conrmam que o complexo de Cobre aumenta a reatividade da molécula. / Understanding the properties of metal complexes is fundamental goal in the development of drugs. However, both from the experimental point of view and theoretical modeling, many diculties in the simulation and evaluatio of the changes that the metal causes upon complexation still remains. This work presents ab initio computational simulations of Epiisopiloturin com plexes with Cu and Zn. We make structural optimizations, simulations of vibrational spectroscopy, NMR and EPR, as well as reactivity studies. We obtain an optimized geometry that corresponds to that of the crystallized form. In addition, the spectroscopic results conrm that the complexes remain intact in solution. Finally, the reactivity studies conrm that the copper complex increases the reactivity of the molecule.
13

X-ray absorption spectroscopy studies of metal coordination complexes and investigations toward novel Actinide/Lanthanide separation methods

Blake, Anastasia V. 01 December 2018 (has links)
Experimentally measuring how ligand modifications affect metal-ligand bonding and electronic structure is an important goal with relevance to diverse fields such as transition metal catalysis and f-element separations. X-ray absorption spectroscopy (XAS) is an excellent technique for investigating structure/function relationships in metal complexes because it can be used to quantify variations in covalent metal-ligand bonding and electronic structure. Here I describe a series of XAS investigations aimed at elucidating how ligand and structural changes affect chemical bonding and properties in transition metal and uranium complexes. The synthesis and characterization of several new classes of f-element complexes are also discussed. Diphosphines are very important ligands in homogeneous catalysis because they can be used to tune reaction rates, the electronic properties of transition metals, and the stereochemistry of catalytic products. P K-edge XAS studies on solid Ni and Pd diphosphine compounds have shown that M-P covalency is not exclusively dependent on the P-M-P angle (i.e. bite angle), which changes as a function of differing linker groups on the diphosphine backbone. Building on these studies, I show how changes in diphosphine bite angle influence Pd-P covalency in solution and when phenyl substituents attached to phosphorus are replaced with alkyl substituents. This work required the development of an improved solid energy calibration standard for routine energy referencing of P K-edge XAS spectra. I discuss the limitations of P K-edge XAS energy standards used previously and propose tetraphenylphosphonium bromide as a new energy calibration standard for future P K-edge XAS work. The use of nuclear power has resulted in critical challenges surrounding the long-term storage and remediation of nuclear waste. Advanced nuclear fuel cycles can address the scientific challenges of nuclear waste, but require the difficult separation of minor actinides and lanthanides. A multi-donor ligand containing a thioether appendage was prepared to determine if it would bind differently to lanthanide and actinide metals, thereby resulting in metal complexes that could be separated due to differing solubilities. In a related study, a new class of homoleptic lanthanide and actinide borohydride complexes called phosphinodiboranates were prepared. I discuss how the differing solution structures of f-element phosphinodiboranates may offer potential for f-element separations. A series of polyoxovanadate alkoxide clusters was synthesized to investigate the underlying electronic properties that make them useful in catalysis and small-molecule activation. The clusters can access four discrete pseudo-reversible one-electron transfer reactions. V K-edge XAS studies were performed to elucidate variations in electronic structure and bonding in the clusters as a function of redox events, and the results indicate that covalency plays a significant role in the one-electron transfer reactions. These results inspired the synthesis and characterization of an actinide polyoxovanadate compound. Activation and functionalization of the oxo bond in UO22+ is important for understanding the fundamental chemistry of uranium and for developing metal separation processes. A novel uranyl polyoxovanadate compound was studied with V K-edge XAS to determine if covalent interactions between the uranium and vanadium metal centers exist (similar to those observed for the polyoxovanadate alkoxide clusters), and if such interactions could be exploited for activation of the oxo bond in the uranyl dication. Results indicate, however, that the U-O bond remains inactivated.
14

Transfert d'électron photoinduit au sein d'assemblages hétérométalliques associant le [Ru(bpy)3]2+ à des complexes bisterpyridine du Fe(II), Co(III) et Cr(III) / Photoinduced electron transfer within heterometallic assemblies of [Ru(bpy)3]2+ linked to bisterpyridine complexes of Fe(II), Co(III) and Cr(III)

Farran, Rajaa 11 September 2015 (has links)
La thèse commence le 1er octobre 2012. IL s'agit pour cette première année de thèse de synthétiser différents complexes de coordination a base du Ruthénium, Fer, Manganèse et de Cobalt à ligands polypyridinique. Ces complexes seront ensuite assemblés par lien covalent. Nous proposons d'utiliser entre autre les techniques d'electrochimie pour induire ces couplages. On cherchera aussi a immobiliser les assemblages sur surface. La principale difficulté attendue dans cette etape du travail concerne la fonctionalisation dissymétrique des ligands pour l'obtention de triade. / This thesis deals with the synthesis and characterization of inorganic triads for photoinduced charge separation. A range of photosensitizers will be studied, and the effect of the donor and acceptor will be assesed as well. These systems will be studied in solution and immobalized on surfaces. Cette thèse traite de la synthèse et la caractérisation des triades inorganiques pour la séparation de charge photoinduite. Une gamme de photosensibilisateurs seront étudiées, et l'effet du donneur et accepteur sera ainsi étudié. Ces systèmes seront étudiés en solution et immobalizes sur les surfaces.
15

TRIAZENOS E COMPLEXOS TRIAZENIDOS DE OURO(I) E COBRE(II): ATIVIDADE ANTILEUCÊMICA E ANTIBACTERIANA IN VITRO / TRIAZENES AND GOLD(I) AND COPPER(II) TRIAZENIDE COMPLEXES: IN VITRO ANTILEUKEMIC AND ANTIBACTERIAL ACTIVITY

Tizotti, Maísa Kräulich 22 March 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Cancer represents one of the leading causes of death worldwide and efforts to discover more effective anticancer therapies have led to the synthesis of a wide diversity of molecular species. Furthermore, the increase of the bacterial resistance has motivated the screening of new antimicrobial agents. Notably, triazenes are a class of compounds with great pharmacological versatility, presenting considerable antitumor and antibacterial activities. Similarly, complexes of gold(I) and copper(II) have been widely targeted as potential therapeutic agents due to the promising results found in several research studies. Thereby, in this work we describe the in vitro antileukemic and antibacterial activity of the 1-(4-amidophenyl)-3-(4-acetylphenyl)triazene and related complex [1-(4-amidophenyl)-3-(4-acetylphenyl)triazenido-N3](triphenylfosphine-P)gold(I) as well as of 1,2,3-benzotriazin-4(3H)-one and three related triazenide complexes of copper(II). The antiproliferative effects on bone marrow cells of the patients with hematological malignancies and of the patients without cancer were evaluated using the bioassay of the reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5diphenyltetrazolium bromide - MTT). Mononuclear cells were incubated with different concentrations of compounds (100 50 12.5 μmol mL-1) during 24 h. Antibacterial activity against Gram-positive and Gram-negative bacteria by the microdilution technique in Mueller Hinton broth was also evaluated. The results revealed that the sensitivity of tumor cells to the complexes was higher than to the free ligands. The best results in terms of in vitro antileukemic activity were achieved with copper(II) complexes, and, among them, the compound named Bis{[1,2,3-benzotriazenide-4-one)-N3](phenanthroline-N1,N10)(μ2-[1,2,3-benzotriazenide-4-one]-N2, N3)}copper(II) was found to be the most efficient. Moreover, this compound had a remarkable activity against Gram-positive and Gram-negative bacteria. The complex [1-(4-amidophenyl)-3-(4-acetylphenyl)triazenido-N3](triphenylfosphine-P)gold(I) exhibited expressive antiproliferative effects, especially on cells from patient with myelodysplastic syndrome (IC50 = 7.72 μmol mL-1). In particular, its cytotoxic activity was significantly higher against tumor cells than against normal cells. In addition, this compound showed pronounced activity against Staphylococcus epidermidis ATCC 12228, Enterococcus faecalis ATCC 29212 and E. faecalis ATCC 51288 (MIC = 8 μg mL-1). Thus, these results suggest that both triazenide complex including the [(triphenylphosphine)gold(I)]-fragment as the triazenide complex of copper(II) with 1,10-phenanthroline provide a strategy for the architecture of new anticancer drugs and antibacterial agents. / As neoplasias representam uma das principais causas de óbito no mundo e esforços para descobrir terapias antineoplásicas mais eficazes têm conduzido à síntese de inúmeras moléculas. Além disso, o aumento da resistência bacteriana tem motivado a pesquisa por novos agentes antimicrobianos. Notoriamente, os triazenos representam uma classe de compostos com ampla versatilidade farmacológica, apresentando atividades antitumorais e antibacterianas consideráveis. Da mesma forma, em razão dos promissores resultados obtidos em diversos estudos, complexos de ouro(I) e cobre(II) vêm sendo amplamente visados como potenciais agentes terapêuticos. Desse modo, neste trabalho descreveu-se a atividade antileucêmica e antibacteriana in vitro de 1-(4-amidofenil)-3-(4- acetilfenil)triazeno e do complexo relacionado [1-(4-amidofenil)-3-(4-acetilfenil)triazenido](trifenilfosfina)ouro(I), assim como, de 1,2,3-benzotriazina-4(3H)-ona e três complexos triazenidos de cobre(II) relacionados. Os efeitos antiproliferativos sobre as células da medula óssea de pacientes com neoplasias hematológicas e de pacientes não acometidos por câncer foram avaliados por meio do ensaio colorimétrico com brometo de 3-(4,5-dimetiltiazol-2-il)-2,5-difeniltetrazólio (MTT). As células mononucleares foram incubadas com diferentes concentrações dos compostos (100 50 12,5 μmol mL-1) durante 24 h. Além disso, foi determinada a atividade antibacteriana destes compostos frente a bactérias gram positivas e gram negativas utilizando-se o método de microdiluição em caldo Mueller Hinton. Os resultados revelaram que a sensibilidade das células tumorais aos complexos foi superior a dos ligantes livres. Os melhores resultados, em termos de atividade antileucêmica in vitro, foram obtidos para os complexos de cobre (II), e, entre eles, o composto denominado Bis{[1,2,3-benzotriazenido-4-ona)-N3](fenantrolina-N1,N10)(μ2-[1,2,3-benzotriazenido-4-ona]-N2,N3)}cobre(II) mostrou-se o mais eficiente. Além disso, este composto apresentou uma notável atividade contra bactérias gram positivas e gram negativas. O complexo [1-(4-amidofenil)-3-(4-acetilfenil)triazenido](trifenilfosfina)ouro(I) exibiu efeitos antiproliferativos expressivos, especialmente em células de paciente com síndrome mielodisplásica (CI50 = 7,72 μmol mL-1). Em particular, a sua atividade citotóxica foi significativamente mais elevada contra células tumorais do que contra células normais. Este composto também apresentou atividade pronunciada contra as bactérias Staphylococcus epidermidis ATCC 12228, Enterococcus faecalis ATCC 29212 e E. faecalis ATCC 51288 (CIM = 8 μg mL-1). Assim, estes resultados sugerem que tanto o complexo triazenido contendo (trifenilfosfina)ouro(I) quanto o complexo triazenido de cobre(II) contendo 1,10-fenantrolina representam uma estratégia alternativa na concepção de novos metalofármacos com propriedades antitumorais e/ou antibacterianas.
16

Luminescence de complexes de lanthanide par effet d'antenne à deux photons : vers l'imagerie fonctionnelle / Luminescence of lanthanide complexes sensitized by two-photon antenna effect : towards functional imaging

Bui, Ngoc Anh Thy 20 September 2016 (has links)
Les ions lanthanides possèdent des propriétés photophysiques particulières, qui ont suscité une forte attention dans le développement de sondes biologiques luminescentes. En effet, les avantages que présentent leurs émissions en raies fines et caractéristiques, ainsi que leurs temps de vie de luminescence longs, permettent diverses applications en imagerie. Cependant, le faible coefficient d’absorption molaire de ces éléments conduit à préférer une excitation par le biais d’une antenne capable de transférer l’énergie au métal.Par ailleurs, l’utilisation de l’absorption biphotonique a montré de nombreux avantages, puisqu’elle permet une excitation de la molécule à une longueur d’onde deux fois plus grande que l’excitation à un photon : cette longueur d’onde peut alors se situer dans la fenêtre de transparence biologique (650 - 1100 nm).Les travaux de cette thèse visent à combiner les avantages des lanthanides avec ceux de l’excitation biphotonique. Les complexes synthétisés sont basés sur une plateforme triazacyclononane substituée par des antennes à deux-photons. Leurs propriétés spectroscopiques à un photon ont été étudiées, et ont alors permis de réaliser des images cellulaires en multiplexing à deux photons utilisant Eu3+ et Tb3+. Des sondes biphotoniques de brillance optimisée ont également été obtenues pour Sm3+, Tb3+ et Dy3+, et appliquées à l'imagerie. L’étude approfondie d’un des complexes de terbium(III) a de plus mis en évidence sa sensibilité à la viscosité. L’analyse des propriétés spectroscopiques de cette sonde a permis d'en rationaliser le comportement photophysique, ouvrant ainsi la voie à des applications originales en imagerie fonctionnelle. Enfin, nous avons montré une internalisation rapide de complexes de lanthanide cationiques de type cyclen ou cyclam par des cellules vivantes, et l'étude de ces nouvelles structures offre de nouvelles perspectives dans le développement de bio-sondes de lanthanides. / Lanthanide ions demonstrate peculiar photophysical properties that has attracted a substantial attention in the development of luminescent bioprobes. Indeed, the advantages stemming from their sharp and characteristic emissions, as well as their long luminescence lifetimes, enable various imaging applications. However, the weak molar extinction coefficient of these elements results in a preferential excitation through an antenna, which transfers its energy to the metal.On the other hand, biphotonic absorption showed numerous advantages, since excitation of a molecule can be achieved at a wavelength twice as high as using one-photon excitation. This wavelength may therefore reach the optical transparency window (650 - 1100 nm).The work carried out during this PhD thesis aims at combining the advantages of lanthanides with those of biphotonic excitation. The synthesized complexes are based on a triazacyclononane platform substituted with two-photon antennae. Their one-photon spectroscopic properties have been studied, and enabled to perform two-photon multiplexed cellular imaging, using Eu3+ and Tb3+. Biphotonic probes with an optimized brightness have been obtained for Sm3+, Tb3+ and Dy3+, and applied to cell imaging. The thorough study of one of the terbium(III) complexes has moreover displayed evidence of a sensitivity towards viscosity. Analyzing the spectroscopic properties of this probe has therefore allowed to rationalize its photophysical behavior, paving the way for original functional imaging applications. Lastly, a rapid internalization of cationic lanthanide complexes with a cyclen or cyclam framework by living cells has been proved. Thus, the study of these new structures presents new perspectives for the development of lanthanide bioprobes.
17

Synthesis, Characterization, and Reactivity of Novel Zinc Coordination Complexes

Ritch, Grayson D. 16 May 2014 (has links)
No description available.
18

Synthèse et coordination de triazacyclononanes et de dérivés bifonctionnels : vers des applications en imageries médicales / Synthesis and coordination of triazacyclononanes and bifunctional derivatives : toward applications in medical imaging

Guillou, Amaury 29 November 2018 (has links)
Le 1,4,7-triazacyclononane (tacn) fait partie de la famille des polyazamacrocycles et a la faculté, lorsqu’il est N-fonctionnalisé par des groupements coordinants adéquats, de former des complexes de coordination stables thermodynamiquement et inertes cinétiquement avec les métaux de transition. C’est pourquoi les dérivés du tacn trouvent de nombreuses applications dans de nombreux domaines, par exemple celui de l’imagerie médicale. Notre équipe a développé des ligands N-fonctionnalisés par des groupements picolinate et méthylpyridine pour des applications en imagerie TEP et IRM.Le premier travail de cette thèse porte sur l’élaboration de nouvelles sondes bimodales TEP-imagerie optique et IRM-imagerie optique à motifs issus de tacn-picolinate décrits au laboratoire.Une seconde partie est axée sur la synthèse de nouveaux chélates du Cu(II) à base de tacn portant des bras méthylthiazole pour une potentielle application en imagerie TEP. Les complexes de Cu(II) correspondant ont été étudiés par différentes méthodes analytiques et spectroscopiques afin de juger leurs stabilités thermodynamiques et leurs inerties cinétiques.Les chélatants répondant aux critères imposés par le milieu biologique ont été sélectionnés pour une application en imagerie TEP dans le cadre du cancer de la prostate. Des analogues bifonctionnels ont ainsi été élaborés afin de les incorporer dans des radiopharmaceutiques radiomarqués au cuivre-64. / The 1,4,7-triazacyclononane (tacn) is part of the family of polyazamacrocycles, and has the faculty, when appropriately N-functionalized with coordination pendants, to form thermodynamically stable and kinetically inert coordination complexes with transition metals. Thanks to their properties tacn derivatives can be found in numerous applications such as medical imaging. Our group has developed some ligands N-functionalized with picolinate and picolyl pendants for an application in PET imaging and MRI.The first part of this thesis is focused on the development of a new class of bimodal PET-optical imaging and MRI-optical imaging probes based on tacn-picolinate units described in the laboratory.The second part deals with the synthesis of new Cu(II) chelators based on tacn-methylthiazolyl units for a potential application in PET imaging. The corresponding Cu(II) complexes were studied by different analytical and spectroscopic methods in order to evaluate their thermodynamic stabilities and kinetic inertness.The chelators that fullfiled all the criterias imposed by the biological media were selected for an applicationPET imaging of prostate cancer. Some bifunctional analogues were elaborated so as to incorporate them in radiopharmaceuticals radiolabeled with copper-64.
19

Organometallic synthons for highly conjugated redox-active materials

Schauer, Philip A January 2009 (has links)
[Truncated abstract] This thesis describes various synthetic approaches toward the synthesis of highly conjugated complexes incorporating multiple transition metal centres. Particular attention is given to the synthesis of mononuclear complexes that allow for the facile assembly of discrete oligo- and poly-nuclear complexes in a controlled, stepwise fashion. Conjugated multi-metallic materials are of interest on account of their unique photophysical and electronic properties, with a particular emphasis on elucidating the nature of intramolecular communication between multiple metal centres. Chapter 1 provides a survey of these topics and current research efforts in the field. Chapter 2 describes the synthesis of Group-VIII allenylidene complexes incorporating a terminal bipyridyl moiety that provides a site for further coordination. The new compound 9-hydroxy-9-ethynyl-4,5-diazafluorene was synthesised, and reaction of this proligand with a coordinatively unsaturated metal fragment yields the allenylidene complexes [MCl(PnP)2=C=C=(4,5-diazafluoren-9-yl)]PF6 (M = Ru, PnP = dppm, dppe, dmpe; M = Os, PnP = dppm) and [CpRu(dppe)=C=C=(4,5-diazafluoren- 9-yl)]PF6. The dmpe-ligated complex is particularly susceptible to decomposition, though it was possible to obtain partial spectroscopic characterisation in addition to a single-crystal X-ray structural determination. The remaining allenylidene complexes are stable compounds readily characterised by standard spectroscopic and electrochemical means, with the bis(diphosphine) complexes characterised by single crystal X-ray structural determinations. ... Reactions of the proligand with [RuCl(PnP)2]+ (PnP = dppm, dppe) led to the isolation of a product spectroscopically consistent with the formation of the target cationic allenylidene complexes, though the complexes were not readily purified and the identity of the accompanying anion was not elucidated. The new compound 4-hydroxy-4- ethynyl-cyclopentadithiophene was also prepared, though the compound was found to be highly unstable and susceptible to rapid decomposition. The derived allenylidene complexes [RuCl(PnP)2=C=C=(4-cyclopentadithiophene)]PF6 (PnP = dppm, dppe) were isolated in a pure form and the complexes stable toward spontaneous decomposition. The thienyl-derived allenylidene complexes were characterised by spectroscopic and electrochemical techniques, with a single-crystal X-ray structural determination undertaken for [RuCl(dppm)2=C=C=(4-cyclopentaditiophene)]PF6. Electrochemical properties are significantly different between the complexes, and also show significant variation between electrodes and solvents. The terminal thienyl substituents are electroactive and show one or two oxidation processes consistent with oligomerisation of the thienyl moiety in dichloromethane solvent, and in acetonitrile solvent cyclic voltammograms are consistent with the deposition of an electroactive film on the electrode surface. The electro-polymerisation of the thienylallenylidene complexes offers a promising new route toward multi-metallic allenylidene complexes.
20

Σχεδιασμός, σύνθεση και κρυσταλλική μηχανική συμπλόκων ενώσεων του Cu(II) με 2-φαινυλοϊμιδαζόλιο ως υποκαταστάτη

Κίτος, Αλέξανδρος 19 July 2012 (has links)
Βασικός στόχος της παρούσης Διπλωματικής Εργασίας ήταν η μελέτη της κρυσταλλικής μηχανικής συμπλόκων ενώσεων του CuII με το 2-φαινυλοϊμιδαζόλιο ως υποκαταστάτη. Η κρυσταλλική μηχανική μπορεί να θεωρηθεί ως ο κλάδος της υπερμοριακής χημείας στη στερεά κατάσταση. Η υπερμοριακή χημεία (supramolecular chemistry) είναι μια από τις πλέον δημοφιλείς και γρήγορα αναπτυσσόμενες περιοχές της πειραματικής χημείας. Χαρακτηρίζεται ως η χημεία των ασθενών διαμοριακών δυνάμεων και εστιάζει στη δομή και λειτουργία χημικών συστημάτων με υψηλή πολυπλοκότητα (υπερμόρια) που προκύπτουν από το συνδυασμό δύο ή περισσοτέρων διακριτών χημικών ειδών (μορίων, ιόντων) και συγκρατούνται με ασθενείς (και αντιστρεπτές) διαμοριακές δυνάμεις (π.χ. αλληλεπιδράσεις π-π, δεσμούς υδρογόνου, υδρόφοβες αλληλεπιδράσεις, δυνάμεις van der Waals, αλληλεπιδράσεις διπόλου-διπόλου, δεσμούς ένταξης μετάλλου-υποκαταστάτη κλπ). Ένα σημαντικό πεδίο της υπερμοριακής χημείας είναι αυτό της κρυσταλλικής μηχανικής (crystal engineering) που αναφέρεται στη στρατηγική σχεδιασμού ενός κρυσταλλικού υλικού με επιθυμητές ιδιότητες και βασίζεται στην κατανόηση και τον έλεγχο των διαμοριακών αλληλεπιδράσεων των μορίων στην κρυσταλλική κατάσταση. Καταρχήν, πραγματοποιήθηκε η σύνθεση συμπλόκων ενώσεων με γενικό τύπο ΜΙΙ/Χ-/L, όπου ΜΙΙ = CuII, X- = Cl-, NO3-, ClO4-, SiF62-, SO42- και L = 2-φαινυλοϊμιδαζόλιο. Από τις συνθετικές παραμέτρους που μεταβάλλαμε -γραμμομοριακή αναλογία μετάλλου:υποκαταστάτη, πολικότητα του διαλύτη (MeOH, EtOH, MeCN, DMF, CH2Cl2), συνθήκες θερμοκρασίας και μέθοδο κρυστάλλωσης– απομονώσαμε και χαρακτηρίσαμε τα σύμπλοκα: (LH)+(NO3)- (1), [CuCl2L2] (2), [Cu2(OMe)2(L)4(NO3)2]∙2MeOH (3∙2MeOH), [Cu(L)4](NO3)2 (4), [Cu2(OMe)2(L)4](ClO4)2 (5), [Cu(L)4](ClO4)2 (6), [Cu2(OMe)2(L)4]SiF6 (7) και [Cu2(SO4)2(L)4] (8). Με τη βοήθεια της κρυσταλλογραφικής ανάλυσης με ακτίνες Χ των ανωτέρων συμπλόκων, διαπιστώθηκε ότι οι διαμοριακές αλληλεπιδράσεις που είναι υπεύθυνες για την υπερμοριακή οργάνωση των δομών τους είναι ισχυροί και ασθενείς δεσμοί υδρογόνου και αλληλεπιδράσεις τύπου π-π. Αναλυτικότερα: • Σταθερά μοτίβα διαμοριακών αλληλεπιδράσεων (συνθόνια) σχηματίζονται μεταξύ των τεκτονίων N-H των ιμιδαζολικών δακτυλίων και των ανόργανων ανιόντων X- (Cl-, NO3-, ClO4-, SiF62-, SO42-) ή/και πλεγματικών μορίων διαλύτη, οδηγώντας σε 1D, 2D και 3D υπερμοριακές δομές. • Οι δομές σταθεροποιούνται περαιτέρω μέσω ενδομοριακών (σύμπλοκα 4, 5 και 6) και διαμοριακών (σύμπλοκο 2) αλληλεπιδράσεων τύπου π-π. • Το μέγεθος και το φορτίο των ανιόντων δεν επηρεάζουν τους δομικούς πυρήνες των μορίων, σε αντίθεση με την υπερμοριακή οργάνωση που επηρεάζεται καθοριστικά και οδηγεί σε 2D και 3D αρχιτεκτονικές. / The main target of this diploma thesis was the crystal engineering studies of coordination compounds of CuII using 2-phenylimidazole as ligand. Crystal engineering may be regarded as the solid-state branch of supramolecular chemistry. Supramolecular chemistry is one of the most popular and rapidly developing areas of experimental chemistry. It may be defined as the chemistry of weak intermolecular forces and focuses on the structure and function of chemical systems of high complexity (supermolecules), resulting from the association of two or more discrete chemical species (molecules, ions) held together by weak (and reversible) intermolecular forces (e.g. π-π interactions, hydrogen bonds, hydrophobic interactions, van der Waals forces, dipole-dipole interactions, metal-ligand coordination bonds etc). Crystal engineering is an important field of supramolecular chemistry that refers to the design and synthesis of a crystalline material with desired properties, based on the understanding and exploitation of intermolecular interactions in the crystalline state. Initially the synthesis of coordination complexes with general formula ΜΙΙ/Χ-/L [ΜΙΙ = CuII, X- = Cl-, NO3-, ClO4-, SiF62-, SO42- and L =2-phenylimidazole] took place. By altering the parameters of synthesis –metal:ligand molar ratio, solvent polarity (MeOH, EtOH, MeCN, DMF, CH2Cl2), temperature, as well as crystallization method– we were able to isolate and study the following complexes: (LH)+(NO3)- (1), [CuCl2L2] (2), [Cu2(OMe)2(L)4(NO3)2]∙2MeOH (3∙2MeOH), [Cu(L)4](NO3)2 (4), [Cu2(OMe)2(L)4](ClO4)2 (5), [Cu(L)4](ClO4)2 (6), [Cu2(OMe)2(L)4]SiF6 (7) και [Cu2(SO4)2(L)4] (8). Based on the X-ray crystal structure determination of the above complexes, it was established that the intermolecular interactions responsible for the supramolecular organization of the structures are strong and weak hydrogen bonds, as well as π-π interactions. Specifically: • Supramolecular synthons between the N-H tectons of imidazole rings and the inorganic anions X- (Cl-, NO3-, ClO4-, SiF62-, SO42-) or/and lattice solvent molecules are formed, leading to 1D, 2D and 3D supramolecular structures. • The structures are further stabilized by intramolecular (complexes 4, 5 and 6) and intermolecular (complex 2) π-π interactions. • The size and charge of the anions X- used does not affect the structural core of the complexes, in contrast to their supramolecular organization which is decisively affected, leading to 2- and 3D architectures.

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