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Development of an epoxy mixed-matrix composite system using an ionic liquid-based coordination polymerJadhav, Sainath Ashok 14 November 2022 (has links)
No description available.
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[pt] ESTUDOS MAGNÉTICOS E FOTOLUMINESCENTES DE COMPOSTOS DE COORDENAÇÃO CONTENDO LIGANTES CARBOXILATO E/OU DOADORES NITROGENADOS COMPLEXADOS A ÍONS METÁLICOS DE TRANSIÇÃO OU LANTANÍDEOS / [en] MAGNETIC AND PHOTOLUMINESCENCE STUDIES OF COORDINATION COMPOUNDS CONTAINING CARBOXYLATO AND/OR N-DONOR LIGANDS COMPLEXED TO TRANSITION OR LANTHANIDE METAL IONSHENRIQUE VON PRESSENTIN HOLLAUER 13 January 2025 (has links)
[pt] O magnetismo molecular tem despertado muito interesse devido a possível aplicação em componentes de materiais eletrônicos. Esses tipos de materiais podem ser criados através de compostos de coordenação, como os polímeros de coordenação, que têm a capacidade de serem materiais multifuncionais. Neste trabalho foram sintetizados 11 compostos inéditos, divididos em dois sistemas que diferem conforme a composição dos materiais. O primeiro sistema utilizou a mistura do ligante policarboxilato BTB e do ligante N-doador como phen e dmdpy para avaliar a influência desses ligantes auxiliares na estrutura e propriedades dos complexos. A família que utiliza fen como ligante auxiliar gerou dois polímeros de coordenação isomorfos 1D com Cu(2+) e Co(2+) como íons metálicos. Medições de EPR para o polímero Cu(2+) não mostraram quase nenhuma interação magnética entre íons metálicos. Devido ao fato de ambos os CPs serem isomorfos, as mesmas pequenas interações magnéticas eram esperadas para o Co(2+) CP, o que é um indicativo do possível comportamento da molécula magnética devido ao forte ZFS de cobalto. A medição da suscetibilidade magnética fora de fase mostrou o comportamento do nanoímã. Um tempo de relaxação de tensão no ponto de escoamento = 5,52(4) × 10(-7)s e barreira de energia de 12,1(3) K foram determinados para este complexo. A mudança do ligante doador de N de phen para dmdpy resultou em um dímero de Cu(2+)pentacoordenado, porém, como o ligante divergente para ambas as famílias era o mesmo, a pequena interação entre os íons cobre(II) foi obtida, como evidenciado por EPR e magnetização medições. O segundo sistema apresenta íons Ln(3+) com ácido cumarínico-3-carboxílico como ligante orgânico, onde duas famílias diferentes foram obtidas alterando a proporção de íons Ln e ligante. A primeira família 1D CP foi obtida com ambos os componentes na mesma proporção. Estudos magnetocalóricos foram realizados para o Gd(3+) e o valor de entropia magnética máxima obtido foi menor que o valor esperado. Para os CPs Tb(3+) e Dy(3+) apresentaram potencial como nanoímãs devido ao sinal obtido nas medidas magnéticas dinâmicas. Foram realizados estudos fotoluminescentes para CPs Eu(3+) e Tb(3+), onde foram estimados tempos de vida de emissão de 0,30 ± 0,05 ms e 0,13 ± 0,05 ms. A segunda família obtida apresentou proporção de Ln(3+) e 3-HCCA de 1:3, e resultou em um polímero de coordenação 1D, onde a extensão da cadeia polimérica teve o mesmo mecanismo. Foram realizados estudos fotoluminescentes para CPs Eu(3+) e Tb(3+), onde foi observado um aumento no tempo de vida da emissão de 0,30 ± 0,05 ms para 0,45 ± 0,05 ms para o derivado Eu(3+) devido à remoção de uma molécula de H2O coordenada ao íon európio. Este trabalho resultou, até o momento desta dissertação, na publicação de dois artigos científicos, além de outro adicional que está em processo de review. / [en] Molecular magnetism has created a lot of interest due to its possible
application in components of electronic materials. These types of materials can
be created through coordination compounds such as coordination polymers,
which have the capacity to be multifunctional materials. In this work, we
synthesized a total of 11 new complexes organized in two systems that differ
according to the composition of materials. The first system utilized the mixture
of polycarboxylate ligand BTB and N-donor ligand such as phen and dmdpy to
evaluate the influence of these auxiliary ligands in the complexes structure and
properties. The family utilizing phen as auxiliary ligand generated two isomorph
1D coordination polymers with Cu(2+) and Co(2+) as metal ions. EPR measurements
for Cu(2+) polymer showed almost no magnetic interactions between metal ions.
Due to both CPs being isomorph, the same small magnetic interactions were
expected for Co(2+) CP, which is an indicative of possible magnetic molecule
behavior due to cobalt strong ZFS. Out-of-Phase magnetic susceptibility
measurement showed the nanomagnet behavior. A relaxation time of yield point stress = 5.52(4)
× 10(-7)
s and energy barrier of 12.1(3) K were determined for this complex. The
change of N-donor ligand from phen to dmdpy resulted in a pentacoordinated
Cu(2+) dimer, however, since the divergent ligand for both families was the same,
the small interaction between the copper(II) ions was obtained, as evidenced by
EPR and magnetization measurements.
The second system presents Ln(3+) ions with Coumarin-3-carboxylic acid
as the organic ligand, where two different families were obtained by changing
the proportion of Ln ions and ligand. First family 1D CP were obtained with both
components with the same proportion. Magnetocaloric studies were conducted
for the Gd(3+) and the obtained maximum magnetic entropy value was smaller than the expected value.
For the Tb(3+) and Dy(3+) CPs displayed potential as nanomagnets due to the signal
obtained in dynamic magnetic measurements. Photoluminescent studies for Eu(3+)
and Tb(3+) CPs were conducted, where 0.30 ± 0.05 ms and 0.13 0.05 ms emission
lifetime was estimated. The second family obtained had a Ln(3+) and 3-HCCA
proportion of 1:3, and resulted in a 1D coordination polymer, where the
extension of the polymeric chain had the same mechanism. Photoluminescent
studies for Eu(3+) and Tb(3+) CPs were conducted, where an increase in the emission
lifetime from 0.30 mais ou menos 0.05 ms to 0.45 0.05 ms for Eu(3+) derivate was observed due
to the removal of one H2O molecule coordinated to the europium ion.
This work resulted, at the time of this dissertation, in the publication of
two scientific papers, as well as a submitted paper that is currently under review.
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A highly porous flexible Metal–Organic Framework with corundum topologyGrünker, Ronny, Senkovska, Irena, Biedermann, Ralf, Klein, Nicole, Lohe, Martin R., Müller, Philipp, Kaskel, Stefan 31 March 2014 (has links) (PDF)
A flexible Metal–Organic Framework Zn4O(BenzTB)3/2 (DUT-13) was obtained by combination of a tetratopic linker and Zn4O6+ as connector. The material has a corundum topology and shows the highest pore volume among flexible MOFs. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
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Développement de MOFs fonctionnels sur support solide : application à la photochimie. / Development of functional MOFs on solid support : application to photochemistry.Genesio, Guillaume 19 November 2018 (has links)
Les travaux présentés dans ce manuscrit s’inscrivent dans le cadre général de la conversion et du stockage de l’énergie lumineuse. Dans ce domaine, l’utilisation de MOFs (Metal-Organic Frameworks) polyfonctionnels n’en est qu’à ses débuts et ils sont principalement utilisés sous forme de poudre cristalline. Or le développement de ces MOFs sur un support solide est essentiel dans l’obtention d’un objet technologiquement avancé répondant à des critères industriels. Les travaux réalisés lors de ce projet ont donc porté sur la croissance contrôlée de matériaux hybrides polyfonctionnels de type MOF sur une surface conductrice transparente TCO (Transparent Conductive Oxide). Les différentes fonctionnalités ont été introduites au sein du MOF par intégration d’une partie photosensible et d’une unité catalytique.A partir de systèmes de MOFs modèles à base de zirconium, il a été possible de produire des systèmes polyfonctionnels par modifications directement pendant la synthèse et/ou post synthèse. Le contrôle de la croissance, en maîtrisant les conditions expérimentales lors de la synthèse solvothermale directe in situ, nous a permis d’obtenir une couche de cristaux monodisperses solidement attachés aux supports TCO. Des efforts importants ont également été dédiés à la compréhension des mécanismes de croissance des MOF sur support TCO. Des essais de photodégradation du bleu de méthylène (polluant organique) ont permis de valider le potentiel photochimique de nos dispositifs.La méthodologie développée pour le contrôle de la croissance des MOFs à base de zirconium a été transposée avec succès à des analogues à base de titane, démontrant la portabilité de la stratégie vers d’autres types de MOFs. Ces derniers ont été utilisés en photo-réduction du CO2 lors d’essais préliminaires (collaboration avec le Collège de France) conduisant sélectivement à l’obtention de formiate. / This work is focused on the development of a functionalization method of TCO transparent conductive surfaces (Transparent Conductive Oxide) by hybrid multifunctional materials, Metal-Organic Frameworks (MOFs). Different properties are provided within the MOF by adding different photosensitive and catalytic units. The development of such materials is in its infancy and they have been mainly developed as crystalline powder. However the development of these MOFs onto a solid support is challenging but also essential toward obtaining a technologically advanced device.This project is focused on the growth controlled of MOFs crystals onto TCO support. From a Zirconium material, it was possible to obtain multifunctional systems by changing components directly during the synthesis or by post synthesis modifications. It has been possible to control the growth of materials on the support by direct in situ solvothermal synthesis and to obtain a monodisperse layer of crystals well anchored to the TCO supports. Photodegradation of methylene blue (organic pollutant) has been performed to validate their photoreactivity.The methodology developed with the Zirconium based MOF has been implemented successfully in a similar compound to include higher photosensitizer components and with titanium-based MOFs. It shows the portability of the strategy towards other types of MOFs. They were used in CO2 photo-reduction (in collaboration of the College de France) where selectively of formate production was observed.
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Síntesi, estructura i reactivitat de nous complexos de Cu, Ag i Ni contenint lligands triazamacrocíclics. Aplicacions en l'activació d'enllaçosXifra Garcia, Raül 28 January 2005 (has links)
· S'ha preparat i caracteritzat una família de complexos de Cu(III) contenint lligands triazamacrocíclics, estudiant-se les seves propietats estructurals, espectroscòpiques i redox. Aquesta àmplia família de complexos tenen un gran interès perquè permeten descriure les propietats dels complexos de Cu en un estat d'oxidació poc habitual i a més ens han permès mesurar de manera quantitativa l'efecte Meyerstein.· Una nova família de complexos de Cu(I) amb els lligands triazamacrocíclics es sintetitzada i caracteritzada per tècniques espectroscòpiques i estructurals, demostrant que aquests complexos presenten diferents estructures a l'estat sòlid i en dissolució. Així doncs, mentre que en dissolució es demostra per RMN que es tracta d'una espècie monomèrica, la determinació estructural per difracció de raigs X d'aquests complexos de Cu(I), ens confirma la formació d'espècies polimèriques. Per altra banda, s'ha estudiat la seva reactivitat; a) la seva implicació en la formació de lligands deuterats mitjançant l'intercanvi H/D en condicions suaus i b) la formació de complexos bisfenoxo a partir de la reactivitat entre els corresponents complexos de Cu(I) i oxigen molecular. De la mateixa manera, s'ha preparat el corresponent anàleg de Ag(I) en estat sòlid, obtenint la formació d'un polímer de Ag(I), el qual presenta a l'estat sòlid una estructura en forma de ziga-zaga, diferent a l'estructura del polímer de Cu(I), que és lineal.· S'ha determinat i proposat el mecanisme que té lloc en l'activació de l'enllaç C-H i posterior reacció de transferència per tal d'estabilitzar els productes finals mitjançant una reacció de desproporció. El seguiment de la reacció té lloc mitjançant tècniques espectroscòpiques com UV-vis. Dit seguiment, ens permet determinar les diferents influències electròniques sobre la reacció de formació dels complexos organometàl·lics de Cu(III). A més a més, el seguiment de la reacció a baixa temperatura ens permet determinar espectroscòpica i teòricament la formació d'un intermedi de Cu(II), i mitjançant la determinació dels paràmetres cinètics i termodinàmics es proposa un mecanisme de reacció. Posteriorment, s'ha assajat la reactivitat d'una sal de Cu(II) amb un lligand macrocíclic que conté un grup metil en el carboni orientat cap al centre del macrocicle, implicant la formació d'un intermedi agòstic. De la determinació estructural d'aquest intermedi de CuII i del lligand protonat, s'extreuen una sèrie de conclusions molt interessants, com són la demostració estructural de l'activació de l'enllaç C-C en la primera etapa de formació i de manera anàloga poder comparar-ho amb els sistemes macrocíclics HL2-HL6, demostrant la possible formació d'un intermedi agòstic, on es produeix l'activació de l'enllaç C-H. Aquesta similitud estaria d'acord amb els sistemes HL2-HL6, els quals espectroscòpica i teòricament s'havia detectat la presència d'un intermedi de característiques similars. Degut a l'acidesa d'aquest protó, i gràcies a la presència d'una base com és el propi lligand, aquest podia ésser extret donant lloc a la formació dels corresponents organometàl·lics de Cu(III). Dita estructura també representa un dels pocs exemples d'un organometàl·lic de CuII, un estat d'oxidació poc conegut dins d'aquest camp.· S'ha descrit la reactivitat dels nous complexos organometàl·lics de Cu(III), els quals sota medi pròtic i en condicions àcides o neutres són espècies totalment estables, però en condicions bàsiques o reductores aquestes espècies reaccionen donant lloc a la formació de noves espècies de tipus bisfenoxo, on el Cu es troba en estat d'oxidació +2. S'han caracteritzat mitjançant difracció de RX, on es s'observa l'entorn químic del Cu, la geometria del complex bisfenoxo i l'hidroxilació de l'anell aromàtic.· Finalment, s'ha descrit per primera vegada la síntesi i caracterització d'uns nous complexos organometàl·lics de Ni. Aquests són sintetitzats en base als càlculs teòrics realitzats sobre els nostres sistemes macrocíclics. Per aquests complexos hem investigat l'efecte del metall, canviant el coure per altres metalls de la primera sèrie de transició (Mn, Fe, Co, Ni, Cu, Zn) i de la segona sèrie de transició (Ru, Rh, Pd, Ag). Els resultats demostren que el Ni(II), és el metall que presenta una major capacitat de l'activació de l'enllaç C-H en aquests sistemes aromàtics. Aquests compostos s'oxiden lentament cap a complexos de Ni(III). Per altra banda, l'addició d'una sal de clor sobre una solució d'un complex de Ni(II) permet aïllar el corresponent complex de Ni(III), caracteritzat per ressonància de spin electrònic / · A family of Cu(III) complexes containing triaza macrocyclic ligands has been described and their structural, spectroscopic and redox properties thoroughly investigated. This family is of interest because it allows studying the properties of Cu complexes in the very unusual oxidation state III and furthermore it allows measuring the so called Meyerstein effect in a quantitative manner.· A new family of Cu(I) complexes containing triaza macrocyclic ligands has been synthesized and characterized both in the solid state and in solution by spectroscopic and structural techniques. NMR spectroscopy demonstrates that the complexes adopt monomeric structures in solution. However, X-ray diffraction analyses demonstrate a polymeric nature in the solid state. On the other hand, the reactivity of these complexes in H/D exchange reactions has been studied, demonstrating that these systems are capable of activating the C-H bond of the aromatic ring in deuterated acetone. On the other hand, the Cu(I) complexes are capable of activating O2, leading to intramolecular aromatic hydroxylation, thus generates complexes with the general formula [(CuII2(m-OLi)2]2+. Finally, we have prepared the corresponding Ag(I) compound. X ray analysis shows that the complex adopts a lineal zigzag polymeric structure.· We propose the mechanism for the activation C-H bond by a Cu(II) complex, coupled to a disproportionation reaction. The monitoring of this reaction has been performed at room and at low temperatures, determinating the different electronic influences of the ligand on the organometallic Cu(III) formation reaction. The monitoring at low temperatures allows to observe and spectroscopically characterize a Cu(II) intermediate. Determination of the kinetic and thermodynamic parameters leads us to propose a mechanism for the reaction. By replacing the H with a Me group, we have crystallography characterized the first example of a Cu(II) C-C agostic intermediate. This specie bears spectroscopic resemblance with the Cu(II) species formed in the aromatic C-H bond activation, and thus we propose it to be the analogous Cu(II) intermediate.Both Cu(I) and Cu(III) complexes are known in organocopper chemistry, but a stable Cu(II) complex is seldom reported. Furthermore, this specie constitutes the second example of a Cu(II) organometallic compound reported in the literature.· We have studied the reactivity of organocopper(III) complexes under different conditions to synthesize new bisphenoxo Cu(II) complexes. These bisphenoxo complexes have been characterized by X-ray diffraction.· A new family of Ni(II) complexes containing triaza macrocyclic ligands have been described and their structural and spectroscopic properties thoroughly investigated. In this case, the C-H bond activation is proposed to occur via acid-base reaction. Moreover, a theoretical study of the activation of the C-H bond in aromatic systems by several transition metals has been carried out. For these specific ligands we have investigated the effect of the metal, changing the copper ion by other first (Mn, Fe, Co, Ni, Cu, Zn) and second transition series metals (Ru, Rh, Pd, Ag). The results demonstrate that the Ni(II) is the ion that presents the highest capacity for activating the C-H bond in the aromatic system of the ligand. On the other hand, the addition of a chloride salt to the Ni(II) complex solution allows the formation of a new and extremely rare organometallic Ni(III) complex.
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Ionic liquids as crystallisation media for inorganic materialsAhmed, Ejaz, Breternitz, Joachim, Groh, Matthias Friedrich, Ruck, Michael 09 April 2014 (has links) (PDF)
Ionic liquids (ILs) have made a great impact on materials science and are being explored for potential applications in several disciplines. In this article, we briefly highlight the current state-of-the-art techniques employing ILs as new crystallisation media, working as neutral solvent, template or charge compensating species. The use of an IL as environmental friendly solvent offers many advantages over traditional crystallisation methods. The change from molecular to ionic reaction media leads to new types of materials being accessible. Room temperature ILs have been found to be excellent solvent systems for the crystallisation of a wide range of substances and morphologies ranging from nanoscopic crystals to micro- and even to macroscopic crystals. Moreover, high temperature routes, such as crystallisation from melts or gas phase deposition, have been replaced by convenient room or low temperature syntheses, employing ILs as reaction media. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
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Études Structurales et Photophysiques de Polymères de Coordination de Thiolates de Métaux Monétaires / Structural and photophysical studies of coordination polymers of coinage metals thiolatesVeselska, Oleksandra 17 October 2019 (has links)
Les polymères de coordination (PCs) à base de thiolates de métaux monétaires sont bien connus pour leurs propriétés luminescentes. Cependant, leurs structures sont sous-explorées. Dans cette thèse, nous présentons une étude pionnière visant la compréhension de la formation de la structure et de la corrélation ‘structure-propriétés’ des PCs homoleptiques neutres, [M(SR)]n, M = Cu(I), Ag(I), Au(I). Les composés avec les dérivés du thiophénolate étudiés dans ce travail, illustrent comment l'utilisation de certains ligands organiques fonctionnalisés conduit à la formation de réseaux 2D étendus ou de colonnes 1D par l'addition d'un encombrement stérique. De plus, la première étude structurelle comparative des PCs thiolées amorphes a été réalisée par analyse PDF. Les études photophysiques ont montré la diversité des propriétés luminescentes des PCs à base de thiolates de métaux monétaires. Des pics d'émission doubles ou multiples, un rendement quantique élevé, des émetteurs orange à proche infrarouge, des variations significatives de durée de vie en fonction de la température... toutes ces propriétés intrinsèques révèlent le potentiel élevé de ces composés pour diverses applications optiques / The coordination polymers (CPs) based on thiolates of coinage metals are well known for their luminescence properties. However, their structures stayed underexplored. In the thesis we present a pioneering study targeting the understanding of the structure formation and the ‘structure-properties’ correlation for neutral homoleptic CPs, [M(SR)]n, M = Cu(I), Ag(I), Au(I). The compounds with thiophenolate derivatives studied in the work, illustrate how the use of some functionalized organic ligands leads to the formation of extended 2D networks or 1D columns by addition of some steric hindrance. The first comparative structural study of amorphous thiolated CPs was performed by PDF analysis. The photophysical studies showed the diversity of luminescent properties of the CPs based on thiolates of coinage metals. Double or multiple emission peaks, high quantum yield of orange-toinfrared emitters, significant lifetime variation with temperature… all of these intrinsic properties reveal the high potential of these compounds for diverse optical applications
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A highly porous flexible Metal–Organic Framework with corundum topologyGrünker, Ronny, Senkovska, Irena, Biedermann, Ralf, Klein, Nicole, Lohe, Martin R., Müller, Philipp, Kaskel, Stefan January 2011 (has links)
A flexible Metal–Organic Framework Zn4O(BenzTB)3/2 (DUT-13) was obtained by combination of a tetratopic linker and Zn4O6+ as connector. The material has a corundum topology and shows the highest pore volume among flexible MOFs. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
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Ionic liquids as crystallisation media for inorganic materialsAhmed, Ejaz, Breternitz, Joachim, Groh, Matthias Friedrich, Ruck, Michael January 2012 (has links)
Ionic liquids (ILs) have made a great impact on materials science and are being explored for potential applications in several disciplines. In this article, we briefly highlight the current state-of-the-art techniques employing ILs as new crystallisation media, working as neutral solvent, template or charge compensating species. The use of an IL as environmental friendly solvent offers many advantages over traditional crystallisation methods. The change from molecular to ionic reaction media leads to new types of materials being accessible. Room temperature ILs have been found to be excellent solvent systems for the crystallisation of a wide range of substances and morphologies ranging from nanoscopic crystals to micro- and even to macroscopic crystals. Moreover, high temperature routes, such as crystallisation from melts or gas phase deposition, have been replaced by convenient room or low temperature syntheses, employing ILs as reaction media. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
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Immobilisierung von Palladium mittels 1,4-Bis-(4‘-pyrazolyl)benzen und dessen Anwendung in der heterogenen Katalyse: Immobilisierung von Palladium mittels 1,4-Bis-(4‘-pyrazolyl)benzen und dessen Anwendung in der heterogenen KatalyseLiebold, Claudia 18 March 2013 (has links)
Die Immobilisierung homogener Katalysatoren ist eine wichtige Methode zur Realisierung der Abtrennbarkeit und Wiederverwendbarkeit aktiver Spezies. Im Rahmen dieser Arbeit wurde durch die Komplexierung von Palladium mit 1,4-Bis-(4′-pyrazolyl)benzen ein neues mikroporöses Koordinationspolymer generiert und dieses als heterogener Katalysator in der Suzuki-Miyaura-Kreuzkupplungsreaktion erfolgreich eingesetzt. Dabei konnten vollständige Umsätze und hohe Selektivitäten erzielt werden, die vergleichbar zu bereits kommerziell erhältlichen homogenen Katalysatoren sind. Die Besonderheit des Katalysators ist, neben dessen außergewöhnlich hohen chemischen Stabilität, die Variation seiner Struktureigenschaften durch die Wahl der Synthesebedingungen und die damit verbundene Steuerung seiner katalytischen Aktivität.:1 EINLEITUNG 1
2 KENNTNISSTAND 5
2.1 Immobilisierung von Palladium 5
2.1.1 Organische Trägermaterialien 6
2.1.1.1 Polyanilin 6
2.1.1.2 Polymerverankerte Phosphanliganden 8
2.1.1.3 Imprägnierung komplexfunktionalisierter Polymere 10
2.1.2 Anorganische Trägermaterialien 11
2.1.2.1 Aktivkohle 11
2.1.2.2 Metalloxide 13
2.1.3 Hybridmaterialien 14
2.1.3.1 Infinite Coordination Polymers 14
2.1.3.2 Metal-Organic Frameworks 17
2.2 Die Suzuki-Miyaura-Kreuzkupplungsreaktion 24
2.2.1 Allgemeine mechanistische Vorstellungen zur Reaktion 27
2.2.2 Die PdII/PdIV-Katalyse – Ein umstrittener Mechanismus 29
3 AUFGABENSTELLUNG UND LÖSUNGSSTRATEGIE 33
4 ERGEBNISSE UND DISKUSSION 38
4.1 Charakterisierung des Koordinationspolymers [Pd(BPB)]n 38
4.1.1 Bis(triphenylphosphan)palladium(II)dichlorid als Palladiumprecursor 38
4.1.1.1 Synthese und Charakterisierung 38
4.1.1.2 Porosität 49
4.1.1.3 Oxidationsstufe des Palladium 57
4.1.1.4 Strukturdiskussion 64
4.1.2 Mechanistische Untersuchungen zur Bildung von [Pd(BPB)]n 74
4.1.2.1 Verfolgung des Reaktionsablaufes mittels Kernresonanzspektroskopie 74
4.1.2.2 Vorschläge zum Reaktionsmechanismus 81
4.1.3 Alternative Palladiumprecursoren für [Pd(BPB)]n 88
4.1.3.1 Bis(triphenylphosphan)palladium(II)dibromid 88
4.1.3.2 Natriumtetrachloropalladat 90
4.1.3.3 Weitere Palladiumprecursoren 93
4.1.4 Alternative Synthesetechniken für [Pd(BPB)]n 94
4.1.4.1 Solvothermale Synthese 94
4.1.4.2 Basendiffusionsmethode 95
4.2 Heterogen katalysierte Suzuki-Miyaura-Reaktion mit [Pd(BPB)]n 97
4.2.1 Verifizierung des Versuchsablaufes mittels Vergleichskatalysatoren 97
4.2.2 Die katalytische Aktivität von [Pd(BPB)]n in der Suzuki-Reaktion 100
4.2.3 Katalysatorstabilität und Wiederverwendbarkeit von [Pd(BPB)]n 104
4.2.4 Einfluss der Reaktionstemperatur 110
4.2.5 Einfluss des phosphanhaltigen Palladiumprecursors 114
5 ZUSAMMENFASSUNG 116
A EXPERIMENTELLER TEIL 120
A.1 Synthese und Charakterisierung von [Pd(BPB)]n 120
A.1.1 Arbeitstechniken und verwendete Chemikalien 120
A.1.2 Synthesevorschriften für [Pd(BPB)]n 122
A.1.2.1 Darstellung von 1,4-Bis-(4′-pyrazolyl)benzen (H2BPB) 122
A.1.2.2 Fällungssynthese von [Pd(BPB)]n 122
A.1.2.3 Solvothermale Synthese von [Pd(BPB)]n 123
A.1.2.4 Diffusionskontrollierte Synthese von [Pd(BPB)]n 124
A.1.2.5 Synthese aus Natriumtetrachloropalladat 124
A.1.2.6 Synthese aus Palladiumacetat 124
A.1.2.7 Synthese aus PdBr2(PPh3)2 125
A.1.3 Charakterisierung von [Pd(BPB)]n 125
A.2 Durchführung der Suzuki-Miyaura-Reaktion 127
A.2.1 Umsetzung von 4-Bromacetophenon mit Phenylboronsäure 127
A.2.2 Katalysatorstabilität und Wiederverwendbarkeit 128
A.2.3 Analyse und Identifizierung der Reaktionsprodukte 129
B ANHANG 134
B.1 Charakterisierung von [Pd(BPB)]n 134
B.2 Mechanistische Untersuchungen zur Bildung von [Pd(BPB)]n 140
B.3 Katalytische Aktivität von [Pd(BPB)]n 141
B.4 Tabellenverzeichnis 143
B.5 Abbildungsverzeichnis 145
B.6 Symbole und Abkürzungen 150
B.7 Literaturverzeichnis 154
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