Dissertations / Theses on the topic 'Catalytic application'

Aquesta tesi doctoral abasta el disseny i el desenvolupament de catalitzadors supramoleculars derivats de metalls de transició per a la seva aplicació com a catalitzadors en transformacions d'interès. La primera part d'aquesta tesi doctoral està centrada en el desenvolupament de catalitzadors de coure(I) regulats supramolecularment i la seva aplicació en reaccions d'inserció d'espècies carbèniques metàl·liques a enllaços O–H, generant derivats α-alquil/aril-α-alcoxi/ariloxi. S’abordà el disseny, preparació, caracterització i aplicació dels catalitzadors de coure(I) derivats de lligands bisoxazolina. Aquests estudis van demostrar que l'activitat catalítica es podia modular amb l'ús de molècules externes (agents de regulació), que interaccionaven amb la cadena polioxietilènica del lligand (centre de regulació) a través d'interaccions supramoleculars de tipus ió-dipol. L'eficiència d'aquesta aproximació es demostrà en reaccions d’inserció de carbens metàl·lics sobre alcohols estructuralment diversos (derivats cicloalquílics, alquílics i arílics). Aquesta metodologia es va utilitzar també per a preparar intermedis sintètics avançats de compostos amb rellevància biològica. La segona part d'aquesta tesi doctoral està centrada en l'ús d'interaccions de tipus halogen per formar l'esquelet de complexos metàl·lics. Es descriu la síntesis de nous complexos supramoleculars de platí(II) i pal·ladi(II) mitjançant l'assemblatge de dos blocs constituents que contenen fosfines com a grups coordinants, així com grups capaços de formar enllaços de tipus halogen. Es va caracteritzar en dissolució i a l’estat sòlid un conjunt de complexos estructuralment diversos de platí(II) i pal·ladi(II) derivats de difosfines (supramoleculars). Es va realitzar un ampli estudi dels intermedis de reacció que van conduir als complexos de platí(II) finals. Es proposa una racionalització mecanística de la formació dels complexos de platí(II) finals. El complex XBPhos-Pt va resultar ser inactiu en reaccions de ciclació d’enins i d’hidrofenilació de l’etilè. Es presenten estratègies d’activació del complex XBPhos-Pt i anàlegs per a noves transformacions químiques.
Esta tesis doctoral abarca el diseño y desarrollo de catalizadores supramoleculares derivados de complejos de metales de transición para su aplicación como catalizadores en transformaciones de interés. La primera parte de esta tesis doctoral se centra en el desarrollo de catalizadores de cobre(I) regulados supramolecularmente para su aplicación en reacciones de inserción de especies carbénicas metálicas a enlaces O–H, generando derivados α-alquilo/arilo-α-alcoxi/ariloxi. Se abordó el diseño, preparación, caracterización y aplicación de los catalizadores de cobre(I) derivados de ligandos bisoxazolina. Estos estudios demostraron que la actividad catalítica podía modularse con el uso de moléculas externas (agentes de regulación), que interaccionaban con la cadena polioxietilénica del ligando (centro de regulación) a través de interacciones supramoleculares de tipo ion-dipolo. La eficiencia de esta aproximación se demostró en reacciones de inserción de carbenos metálicos sobre alcoholes estructuralmente diversos (derivados cicloalquílicos, alquílicos y arílicos). Esta metodología se utilizó también para preparar intermedios sintéticos avanzados de compuestos con relevancia biológica. La segunda parte de esta tesis doctoral se centra en el uso de interacciones de tipo halógeno para formar el esqueleto de complejos metálicos. Se describe la síntesis de nuevos complejos supramoleculares de platino(II) y paladio(II) mediante el ensamblaje de dos bloques constituyentes que contienen fosfinas como grupos coordinantes, así como grupos capaces de formar enlaces de tipo halógeno. Se caracterizó en disolución y en estado sólido un conjunto de complejos estructuralmente diversos de platino(II) y paladio(II) derivados de difosfinas (supramoleculares). Se realizó un estudio de los intermedios de reacción que condujeron a los complejos de platino(II) finales. Se propone una racionalización mecanística para la formación de los complejos de platino(II) resultantes. El complejo XBPhos-Pt fue inactivo en reacciones de ciclación de eninos e hidrofenilación del etileno. Se presentan estrategias de activación del complejo XBPhos-Pt y análogos para nuevas transformaciones químicas.
This doctoral thesis encompasses the design and development of supramolecular catalysts derived from transition metal complexes and their application as catalysts in transformations of interest. The first part of the thesis focusses on the development of supramolecularly regulated copper(I) catalysts for the insertion of metal carbenes into O–H bonds leading to synthetically useful α-alkyl/aryl-α-alkoxy/aryloxy derivatives. The design, preparation, characterization and application of supramolecularly regulated copper(I) catalysts derived from bisoxazoline ligands is described. Our studies demonstrate that the catalytic performance of these systems can be modulated by the use of an external molecule (i.e. the regulation agent), which interacts with the polyethyleneoxy chain on the ligand (i.e. the regulation site) via supramolecular ion-dipole interactions. This approach has been applied to an array of structurally diverse alcohols (cycloalkyl, alkyl and aryl derivatives). Moreover, this methodology has been used to synthesize advanced synthetic intermediates of biologically relevant compounds. The second part of this thesis focusses on the use of halogen bonding interactions to construct the skeleton of metal complexes. The synthesis of new supramolecular platinum(II) and palladium(II) complexes by assembling two building blocks that incorporate phosphines as ligating groups, as well as complementary binding motifs for the assembly through halogen bonding, are reported. A set of structurally diverse platinum(II) and palladium(II) complexes derived from (halogen-bonded) diphosphines have been characterized in solution and in the solid state. A broad study of the reaction intermediates that led to the platinum(II) complexes has been performed. A tentative mechanistic rationalization for the formation of the platinum(II) complexes is proposed. The complex XBPhos-Pt has proved to be unreactive as a catalyst in cyclizations of enynes and in the hydrophenylation of ethylene. Strategies towards the activation of XBPhos-Pt and analogues for new chemical transformations are presented.

Thesis (MScEng (Process Engineering))--University of Stellenbosch, 2005.
Catalytic Distillation (CD) is a hybrid technology that utilizes the dynamics of si- multaneous reaction and separation in a single process unit to achieve a more compact, economical, efficient and optimized process design when compared to the traditional multi-unit designs. The project goal (and key question) is (how) to design a cost-effective, simple and accurate laboratory-scale continuous CD system that will sufficiently and accurately supply useful data for model validation. The system to be investigated is the continuous hydrogenation of an a-olefin C6 (1-hexene) feed stream to the corresponding alkane (n-hexane) product with simultaneous reactant/product separation. Hypothetically, a system can be constructured to determine whether hydrogenation will benefit from the heat and mass transfer integration observed under CD conditions in terms of energy usage, temperature control and the catalyst's surface hydrogen concentration. System convergence with commercial distillation simulation packages ...

Radiofrequency (RF) heating of composite magnetic materials enables direct and efficient transfer of energy to the sites of catalytic reactions within a chemical reactor. The materials consist of an RF heated magnetic component and a catalytic component. The two components can be optimised separately according to the demands of the application. This approach was applied to continuous direct amide formation from amines and carboxylic acids under flow conditions, a reaction of great interest and potential to the pharmaceutical industry. The RF heat generation of NiFe2 04-TiO2 magnetic materials were optimised. Catalyst screening showed sulfated commercial P 25 Ti02 to give good catalytic activity in the reaction of 4-phenylbutyric acid with aniline in xylene. The composite material was prepared mechanochemically from a mixture of the optimised magnetic and catalytic components. A continuous RF heated reactor was developed, consisting of a 6 mm diameter insulated micro packed-bed reactor placed within an RF induction coil. The reactor was operated at 7 bar and up to 200°C for up to 10 hours. The sulfated composite achieved t he highest activity of up to 50% conversion in a single pass and the least deactivation. Temperature profiles obtained from the analytical solutions were combined with a catalyst kinetic model to form a reactor model, which was validated by the experimental results. The concentration profiles obtained from the reactor model gave an insight into the mechanism of the observed process intensification - the temperature rise along the RF heated reactor axis helped to offset the reduction in the reaction rate as a result of depletion of the reactants. This novel type of process is therefore most suited to reactions with high reaction rate orders and it would therefore be of great interest to investigate other processes where this effect could be demonstrated.

Microflow technology has become an innovative and fashionable tool in synthetic organic chemistry, opening the way to novel challenging interactions between chemistry and other scientific disciplines. The system properties and reaction conditions in microflow chemistry are different to those in flask as a result of higher surface-to- volume ratios and shorter diffusion distances bringing significant advantages over conventional flask method such as improved heat transfer and reduced mixing times. More and more multiphase microflow systems have begun to emerge over the last few years, offering a variety of methodologies. The attention to the various emerging microflow techniques represented the starting point for the development of the present work. The study presented in this thesis focuses on the application of microflow systems using segmented flow technique to various organic transformations by development of a practical and economical system setup in order to provide a basic methodology for synthetic chemists. First, we carried a comparison study between microflow and flask reaction using a simple biphasic hydrolysis under segmented flow. The study was then extended to investigate the effect of parallel vs. segmented flow, in addition to the variation of reaction parameters in the microflow system, such as heating, sonication, and microchannel size. We selected for our study two classes of catalytic organic reactions of particular synthetic relevance, namely palladium-catalysed Heck coupling and ruthenium-catalysed ring-closing metathesis. We carried out biphasic Heck catalysis then moved onto the study of segmented flow application to monophasic reactions both in single step and multistep syntheses. Overall the use of microflow technique, applied to a number of reactions of various types and carried out with many chemical and engineering variables, allowed us to observe overall reaction performances enhancement compared to conventional flask chemistry, on the whole rather agreeably, reproducibly, and displaying very regular trends.

Nanostrukturierte Materialien zeichnen sich dadurch aus, dass sie aus sehr kleinen Baueinheiten zusammengesetzt sind. Typischerweise liegt die Grössenordnung dieser Bausteine im Bereich von einigen Nanometern. Ein Nanometer entspricht 10-9 Meter. Dadurch bekommen nanostrukturierte Materialien oft verbesserte, vielfach sogar ganz neue Eigenschaften, die für viele heutige wie auch zukünftige Anwendungen von Vorteil sind.

Ein Weg, um solche nanostrukturierte Materialien herzustellen, ist die sogenannte „Templatierungsmethode“. Das Templat besteht aus einem einzelnen Molekül, einer Ansammlung von Molekülen oder aus einem festen Objekt. Beim Aufbau des nanostrukturierten Materials wirkt das Templat als Schablone oder als Gussform und beeinflusst damit die Struktur des Endproduktes. Normalerweise besteht dieser Prozess aus mehreren Schritten. Zuerst wird der Raum um das Templat mit dem Ausgangsstoff umhüllt oder ausgefüllt, dann wird der Ausgangsstoff chemisch in das gewünschte Endprodukt umgewandelt, wobei das Templat die Endform kontrolliert und am Schluss wird das Templat entfernt. Das geschieht meistens durch Erhitzen. Als Ausgangsstoff können dabei einzelne Moleküle verwendet werden, die sich leicht in das Endprodukt umwandeln lassen, oder aber vorgeformte Partikelchen, die nur noch zur entsprechenden Form angeordnet werden müssen.

In dieser Arbeit wurden poröse Metalloxid-Kügelchen hergestellt, die aus einem Gemisch aus Titanoxid und entweder Aluminium-, Gallium- oder Indiumoxid bestehen. Als Template wurden poröse Kunststoffkügelchen eingesetzt, die man sonst für Chromatographiezwecke braucht. Bei der Synthese wurden die Poren der Kunststoffkügelchen mit dem Ausgangsmaterial gefüllt und mit Wasser in ein amorphes Netzwerk umgewandelt. Danach werden die Kügelchen erhitzt, wobei das Kunststofftemplat zersetzt wird. Gleichzeitig wird das amorphe Gerüst in stabile, kristalline Wände umgewandelt, die die Form der Kügelchen auch dann noch behalten, wenn das Templat verschwunden ist. Mit einem ähnlichen Prozess wurden auch Kügelchen aus Cer-Zirkonoxid erhalten. Als Ausgangsstoff wurden dabei aber vorgeformte Cer-Zirkonoxid-Nanopartikel eingesetzt, die in die Poren der Kunststofftemplatkügelchen hinein diffundieren. Diese Cer-Zirkonoxid-Nanopartikel lassen sich auch für die Herstellung von porösen Pulvern verwenden, wobei dann nicht Polymerkügelchen, sondern hochgeordnete Ansammlungen von Block Copolymeren als Template verwendet werden.

Form, Struktur und Eigenschaften all dieser Materialien wurden systematisch unter Anwendung verschiedenster Analysemethoden untersucht. Die auf Titanoxid-basierten Kügelchen wurden auch auf ihre photokatalytische Verwendung zum Abbau von umweltschädlichem 2-Chlorophenol untersucht. Die Cer-Zirkonoxid-Kügelchen wurden für die Herstellung von Wasserstoff aus Methanol getestet. Wasserstoff gilt als hoffungsvoller, sauberer Energieträger der Zukunft und kommt in Brennstoffzellen zum Einsatz.
Nanostructured materials are the materials having structural features on the scale of nanometers i.e. 10-9 m. the structural features can enhance the natural properties of the materials or induce additional properties, which are useful for day to technology as well as the future technologies

One way to synthesize nanostructured materials is using templating techniques. The templating process involves use of a certain “mould” or “scaffold” to generate the structure. The mould is called as the template, can be a single molecule or assembly of molecule or a larger object, which has its own structure. The product material can be obtained by filling the space around the template with a “precursor”, transformation of precursor into the desired material and then removal of template to get product. The precursor can be any chemical moiety that can be easily transformed in to the desired material. Alternatively the desired material is processed into very tiny bricks or “nano building blocks (NBB)” and the product is obtained by arrangement of the NBB by using a scaffold.

We synthesized porous metal oxide spheres of namely TiO2-M2O3: titanium dioxide- M-oxide (M = aluminum, gallium and indium) TiO2-M2O3 and cerium oxide-zirconium oxide solid solution. We used porous polymeric beads as templates. These beads used for chromatographic purposes. For the synthesis of TiO2-M2O3 we used metal- alkoxides as precursor. The pore of beads were filled with precursor and then reacted with water to give transformation of the precursor to amorphous oxide network. The network is crystallized and template is removed by heat treatment at high temperatures. In a similar way we obtained porous spheres of CexZr1-xO2. For this we synthesized nanoparticle of CexZr1-xO2 and used then for the templating process to obtain porous CexZr1-xO2 spheres.

Additionally, using the same nanoparticles we synthesized nano-porous powder using self-assembly process between a block-copolymers scaffold and nanoparticles.

Morphological and physico-chemical properties of these materials were studies systematically by using various analytical techniques

TiO2-M2O3 material were tested for photocatalytic degradation of 2-Chlorophenol a poisonous pollutant. While CexZr1-xO2 spheres were tested for methanol steam reforming reaction to generate hydrogen, which is a fuel for future generation power sources like fuel cells. All the materials showed good catalytic performance.

Los procesos de oxidación químicos son una herramienta universal para el tratamiento de aguas subterráneas, efluentes industriales y aguas residuales. Una de estas técnicas se basa en la generación de radicales hidroxilos (•OH), y se le conoce con el nombre de proceso de oxidación avanzada (AOP). Aunque dicho proceso es considerado una poderosa herramienta para la degradación de contaminantes, este enfrenta varias limitación prácticas especialmente en función del sistema seleccionado para la generación de los •OH. El objetivo de este trabajo fue proponer y poner a prueba una estrategia novedosa con el fin de ampliar la aplicabilidad de la oxidación avazanda, integrando al sistema el uso de reactores de membrana catalítica (CMR). Los esfuerzos fueron enfocados en la aplicación de los CMRs para la oxidación de un compuesto orgánico modelo (fenol), utilizando peróxido de hidrogeno generado in situ como fuente de •OH. Las características de los CMRs permiten la síntesis directa de H2O2.
Chemical oxidation processes are the most universal tool for treatment of contaminated groundwater, industrial effluents and wastewater. Oxidation at mild conditions and based on the generation of highly reactive hydroxyl radicals (•OH) is referred to as advanced oxidation process (AOP). Even though this technique is considered as powerful regarding contaminant degradation, it faces several practical limitations in a large scale due to the cost of the system selected for •OH generation. The aim was to propose and test a novel strategy in order to extend the applicability of AOP, whereby the integration of catalytic membrane reactors (CMRs) plays a key role. The efforts were focused on the application of the CMRs for direct oxidation of a model organic compound by the in-situ generated hydrogen peroxide. The inherent properties of the CMRs permit the direct synthesis of hydrogen peroxide starting from H2 and O2 using noble metal as an active phase.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2005.
Includes bibliographical references.
With the rapid advances in kinetic modeling, building elementary surface mechanisms have become vital to understand the complex chemistry for catalytic partial oxidation systems. Given that there is selected experimental knowledge on surface species and a large number of unknown thermochemical, rate parameters, the challenge is to integrate the knowledge to identify all the important species and accurately estimate the parameters to build a detailed surface mechanism. This thesis presents computational methodology for quickly calculating thermodynamically consistent temperature/coverage-dependent heats of formation, heat capacities and entropies, correction approach for improving accuracy in heats of formation predicted by composite G3- based quantum chemistry methods, and detailed surface mechanism for explaining selectivity in ethylene epoxidation. Basis of the computational methodology is the Unity Bond Index- Quadratic Exponential Potential (UBI-QEP) approach, which applies quadratic exponential potential to model interaction energies between atoms and additive pairwise energies to compute total energy of an adsorbed molecule. By minimizing the total energy subject to bond order constraint, formulas for chemisorption enthalpies have been derived for surface species bound to on-top, hollow and bridge coordination sites with symmetric, asymmetric and chelating coordination structures on transition metal catalysts. The UBI-QEP theory for diatomics has been extended for polyatomic adsorbates with empirical modifications to the theory.
(cont.) Formulas for activation energies have been derived for generic reaction types, including simple adsorption, dissociation-recombination, and disproportionation reactions. Basis of the correction approach is the Bond Additivity Correction (BAC) procedures, which apply atomic, molecular and bond- wise modifications to enthalpies of molecules predicted by G3B3 and G3MP2B3 composite quantum chemistry methods available in Gaussian® suite of programs. The new procedures have improved the accuracy of thermochemical properties for open and closed shell molecules containing various chemical moieties, multireference configurations, isomers and degrees of saturation involving elements from first 3 rows of the periodic table. The detailed mechanism explains the selectivity to ethylene oxide based on the parallel branching reactions of surface oxametallacycle to epoxide and acetaldehyde. Using Decomposition Tree Approach, surface reactions and species have been generated to develop a comprehensive mechanism for epoxidation. As a result of these developments in the thesis, chemisorption enthalpies can now be estimated within 3 kcal/mol of experimental values for transition metal catalysts and enthalpies predicted by G3B3 and G3MP2B3 Gaussian methods can be corrected within 0.5 kcal/mol. Examples of heterogeneous reaction systems involving silver-catalyzed ethylene epoxidation demonstrate the effectiveness of the methodologies developed in this work.
by Bharthwaj Anantharaman.
Ph.D.

Ce travail de recherche porte sur la préparation d'assemblages covalents de nanoparticules (NP) de Ru stabilisés par différentes molécules fonctionnelles, ainsi que sur l'étude des relations structure/activité de ces assemblages pour des réactions d'hydrogénation catalytique. Le chapitre 1 passe en revue la bibliographie relative aux assemblages covalents de NP métalliques en fonction des stratégies de synthèse utilisées et de leur application en catalyse. Le chapitre 2 décrit la préparation d'assemblages covalents tridimensionnels (3D) de NP de Ru caractérisés par: a) des NP de Ru de taille nanométrique bien définie, stabilisées par des ligands adamantane, bisadamantane et diamantane fonctionnalisés, et ii) une distance interparticulaire ajustable. La chimie de coordination avec des ligands amine et acides carboxyliques a été étudiée. Dans le cas de ligands d'acide carboxylique, il a été montré que les espèces de Ru formées lors de l'assemblage de NP sont capables de décarbonyler partiellement les ligands d'acide carboxylique à température ambiante. Le mécanisme de cette réaction a été élucidé par DFT. Le chapitre 3 détaille l’utilisation d’autres briques moléculaires élémentaires pour la formation d’assemblages de NP de Ru. Nous avons montré que l'utilisation d'un ligand tricarboxylique-hexyloxy triphénylène conduisait à la formation d'assemblages bidimensionnels (2D) de NP de Ru présentant une distance interparticulaire et une taille de NP homogènes. De plus, des assemblages 3D de NP de Ru ont été préparés avec de l'anthracène 9,10-dicarboxylique et un fullerène C60 fonctionnalisé par un hexa-adduit. Dans le chapitre 4, nous avons étudié les performances catalytiques de ces nouveaux réseaux covalents de NP de Ru dans diverses réactions. Tous ces matériaux constituent un ensemble intéressant pour étudier les effets structurels et électroniques du catalyseur en catalyse hétérogène. Les assemblages sont actifs et atteignent une bonne sélectivité en styrène dans l'hydrogénation sélective du phénylacétylène. En particulier, nous avons démontré que des effets de confinement et des effets électroniques se produisaient et que la distance interparticulaire des NP de Ru affectait l'activité du catalyseur, tandis que les effets électroniques liés aux ligands régissaient principalement la sélectivité du catalyseur. Nous discutons enfin la stabilité des assemblages de NP de Ru
This research work focuses on the preparation of Ru nanoparticle (NP) covalent assemblies stabilized by different functional molecules, and the study of structure/activity relationships for catalytic hydrogenation reactions. Chapter 1 reviews the metal NP covalent assemblies according to the synthesis strategies and their application in catalysis. Chapter 2 described the preparation of three-dimension (3D) Ru NP covalent assemblies characterized by: i) well-defined nanometricsized Ru NP stabilized by functionalized adamantane, bis-adamantane and diamantane ligands, and ii) a tunable interparticle distance. The coordination chemistry with amine and carboxylic acid ligands towards the Ru NP surface was investigated. In the case of carboxylic acid ligands it was shown that Ru species formed during the NP assembly are able to partially decarbonylate carboxylic acid ligands at room temperature. The mechanism of this reaction was elucidated by DFT. Chapter 3 detailed the use of other molecular building blocks for Ru NP assembly formation. We showed that the use of tricarboxylic-hexyloxy triphenylene ligand leads to the formation of twodimensional (2D) Ru NP assemblies with homogeneous interparticle distance and NP size. Additionally, 3D Ru NP assemblies were prepared with 9, 10-dicarboxylic anthracene and a hexaadduct functionalized C60 fullerene. In Chapter 4 we studied the catalytic performances of the Ru NP networks in various reactions. All these materials constitute an interesting set to investigate the structural and electronic effects in heterogeneous catalysis. In the selective hydrogenation of phenyl acetylene, the assemblies are active, reaching good selectivity towards styrene. Especially, we demonstrated that confinement and electronic effects are occurring and that Ru NP interparticle distance affects the catalyst activity, whereas electronic effects mainly govern the catalyst selectivity. The stability of the Ru NP assembly is finally discussed

Currently, neurodegenerative diseases like Alzheimer’s (AD) and Parkinson’s disease (PD) represent an important worldwide health problem. Over the last number of years, there have been many advances in the field of metal catalysed reactions. The palladium-catalysed intramolecular nucleophilic addition of arylborons and aryl halides to ketones constitutes an important methodology for the synthesis of chiral cycloalkanols. Our main objective was the development of a new efficient protocol for accessing the 1-aminotetralin and 1-aminoindane skeletons (Chapters 3 and 4). A secondary goal was to obtain robust and reliable enantioselective versions of these reactions (Chapters 3 and 4). Numerous aldehyde substrates were synthesized and various cyclization reactions were carried out using these substrates (Chapter 3). We also compared the effectiveness of conducting these reactions under continuous flow conditions, with those carried out under batch conditions. Furthermore, some of our 3,3-dimethylchroman-4-ones and 3,3-dimethylchroman-4-ols were tested against AChE and BuChE enzymes. Chapters 1 and 2 contain literature reviews of this material. We also report the attempted synthesis of a library of substituted 3-hydroxy-3-phenylbenzofuran-2(3H)-ones derived from a series of α-keto o-bromoaryl- and o-pinacolboranearyl ester substrates (Chapter 4). For the synthesis of the α-keto ester substrates, we looked at two different methodologies. Eight α-keto ester substrates were synthesized in very high or excellent yields. We also studied the cyclization reaction with 1-bromonaphthalen-2-yl 2-oxo-2-phenylacetate as our model substrate. Unfortunately, these attempts were unsuccessful and no cyclic product was obtained. Additionally, we successfully developed a new methodology for the direct oxidative esterification of aldehydes (Chapter 5). Using this methodology, we synthesized nine new diether-esters in very good to excellent yields, which were subsequently tested for both AChE and BuChE inhibition. We also presented a strategy for the synthesis of interesting polyether macrocycles that includes the borylation of the synthesized diether-esters and a Suzuki-Miyaura coupling; Resumo: Estudos sobre a arilação intramolecular catalítica – Aplicação de sistemas de fluxo contínuo Atualmente, doenças neurodegenerativas como a doença de Alzheimer (DA) e a doença de Parkinson (DP) representam um problema importante de saúde em todo o mundo. Ao longo dos últimos anos, tem havido muitos avanços no campo das reações catalisadas por metais. As reações de adição nucleofílica intramolecular catalisadas por paládio, de arilboronados e de haletos de arilo a cetonas, constituem uma metodologia importante para a síntese de ciclo-álcoois quirais. O nosso objetivo principal foi o desenvolvimento de um novo protocolo eficiente para aceder a esqueletos de 1-aminotetralinas e 1-aminoindanos (capítulos 3 e 4). Um objetivo secundário era obter versões enantiosseletivas robustas e fiáveis dessas reações (capítulos 3 e 4). Numerosos aldeídos foram sintetizados e várias reações de ciclização foram realizadas utilizando estes substratos (capítulo 3). Também comparamos a eficácia da realização destas reações sob condições de fluxo contínuo com aquelas realizadas sob condições de “batch”. Algumas das nossas 3,3-dimetilcroman-4-onas e dos nossos 3,3-dimetilcroman-4-ols foram testados contra a AChE e BuChE. Os capítulos 1 e 2 contêm alguma literatura sobre este material. Também relatamos a tentativa de síntese de uma biblioteca de 3-hidroxi-3-fenilbenzofuran-2(3H)-onas substituídas, derivadas de uma série de α-ceto ésteres e de ésteres de o-bromoaril- e o-pinacolboranaril (capítulo 4). Para a síntese de α-ceto ésteres, testamos duas metodologias diferentes. Oito α-ceto ésteres foram sintetizados com rendimentos muito elevados ou excelentes. Também estudamos a reação de ciclização usando 1-bromonaftalen-2-il-2-oxo-2-fenilacetato como substrato modelo. Infelizmente não obtivemos nenhum produto cíclico. Adicionalmente, desenvolvemos com sucesso uma nova metodologia para a esterificação oxidativa direta de aldeídos (capítulo 5). Usando esta metodologia, sintetizamos nove di-éter-ésteres novos com rendimentos muito bons a excelentes, que foram posteriormente testados para inibição da AChE e da BuChE. Também apresentamos uma estratégia para a síntese de macrociclos de poliéteres interessantes, que incluí a borilação dos di-éter-ésteres sintetizados e um acoplamento Suzuki-Miyaura.

Un aspect clé permettant de surmonter les défis énergétiques et environnementaux est d'améliorer l'efficacité des nouveaux procédés. La plupart des produits chimiques majeurs se faisant par des procédés catalytiques, une meilleure compréhension des cinétiques de réaction est nécessaire. Dans le domaine du traitement des eaux usées, l'ozonation catalytique est en un exemple typique. Dans cette thèse, des microréacteurs catalytiques sont utilisés en tant qu’outils analytiques innovants afin de déterminer la cinétique de l'ozonation catalytique. Ceux-ci ont pu être élaborés à l'aide de procédés plasma en déposant et en activant un catalyseur à base d’oxyde de fer et de cobalt. L’efficacité de ces catalyseurs a été mesurée en utilisant de l'acide pyruvique en tant que polluant modèle. Pour Fe2O3, les mesures HPLC ont montré l'inactivité de celui-ci par rapport à Co3O4 (20%). Cet effet a été doublé après post-traitement par un plasma d'Ar, démontrant ainsi le rôle du plasma. Une simulation numérique portant sur les réactions à la surface du catalyseur a été réalisée en utilisant le logiciel Comsol Multiphysics. Le modèle utilisé s’est partiellement approché des données expérimentales en raison du manque de données concernant les constantes de réactions des espèces intermédiaires. Ces constantes cinétiques pourront être déterminées grâce à l'utilisation de la technique de spectroscopie Raman Anti-Stokes Cohérente (technique CARS) en tant qu’outil d'analyse en temps réel. En perspectives, l’utilisation de cette dernière conduira à l’élaboration d’un outil efficace qui pourrait prédire la pertinence et les futures stratégies d'amélioration sur des réactions chimiques catalysées
A key aspect in overcoming the energy and environmental challenges is to improve the efficiency of existing and new processes. Nowadays, almost all major chemicals are produced by catalytic processes. However, a better understanding of the reaction pathways and kinetics is needed. In the field of wastewater treatment, catalytic ozonation is a typical example of this problem. In this study, catalytic microreactors were used as innovative analytical tools for the determination of kinetics of catalytic ozonation and were elaborated by using low pressure plasma processes for the deposition and activation of iron and oxide-based catalysts on polymer-based materials. Catalytic ozonation with pyruvic acid as a refractory probe compound was performed with both catalysts. HPLC measurements showed the inactivity of the iron oxide layer compared to the cobalt oxide one which led to 20 % of degradation. The effect was doubled when the latter was post-treated by an argon plasma, demonstrating the role and importance of the plasma post-treatment step. A numerical study dealing with the reactions taking place on the surface of the catalyst was carried out using the Comsol Multiphysics software and showed that the model partially fitted the experimental data due to the lack of information. However, access to the reactions rate constants of the intermediate species generated during the catalytic ozonation step could be achieved through the use of the Coherent Anti-Stokes Raman Spectroscopy technique and would lead to an efficient tool to predict the relevance and the direction of future improvement strategies regarding catalyzed chemical reactions

The present Thesis is focused on the development of ceramic membranes for the production of O2, as well as their use in several industrial applications (e.g. power generation, chemical industry). Different materials such as perovskites (BSCF and LSCF), fluorites (CGO) and composites, different membrane architectures have been considered. Catalytic activation was considered for the optimization of permeation, and for improving the selectivity/yield of chemical reactions. In the chapter dedicated to BSCF, the influence of thickness and the use of porous supports in the permeation was studied. An improvement in the permeation was observed for the thinner membranes. With respect to the porous supports, it was found that they contribute with an additional resistance within the permeation process, reducing the potential improvement when reducing thickness. The conducted tests also allowed to study more in deep the different processes affecting oxygen membranes, as well as defining a permeation model for monolithic and asymmetric membranes. Aiming to improve the surface reactions involved in the oxygen permeation the use of catalytic layers was considered, by means the addition of porous BSCF backbones. The best results were obtained when coating both sides of membranes with catalytic layers. The concept of BSCF activated membranes was also considered for the production of C2H4 by means of the oxidative de-hydrogenation of C2H6, obtaining high C2H4 yields. BSCF membranes presenting tubular geometry were characterized for application such as production of O2 and production of C2H4 by means of oxidative coupling of CH4. LSCF was considered for conducting studies under CO2-containing atmospheres. For both systems it was conducted a complete permeation study with a focus on permeation performance under CO2 environments. Furthermore a study focused on the different substrates was carried out for determining the structure presenting the lower gas diffusion resistance. Despite very good results were obtained for both membrane types, even under CO2 conditions, freeze casted membranes reached higher oxygen fluxes, being optimized with the catalytic activation of membranes. Materials presenting fluorite structure stand out for their stability under reaction conditions or when exposed to CO2 environments. Nevertheless, delivered oxygen fluxes are typically low. Hence, a thin 40 micron-thick CGO-Co membrane activated with Pd nanoparticles was considered for conducting a study on O2 permeation performance, and its behaviour when exposed to CO2 and CH4-containing atmospheres. A good stability was demonstrated, as well as a significant improvement in oxygen permeation when exposed to CH4 environments. Thus, CGO membranes present promising properties for their application in oxyfuel and for the conduction of chemical reactions. Composite materials based on NFO-CTO was carried out. An evaluation of the CTO content and its relation with permeation was conducted, determining that a higher ionic phase ratio in the membrane results in a higher permeation. A composite consisting of 50NFO-50CTO was considered for performing a permeation study under harsh application conditions, with presence of SO2. Despite the significant loss in permeation, the composite material resulted to be stable after a long exposure to SO2. A broad study about the effect of CO2 and SO2 on the oxygen surface reactions was conducted by means of EIS measurements on 60NFO-40CTO electrodes. It was observed a significant effect of SO2 on the surface exchange reactions by promoting the deactivation of the O2 active sites, due to a SO2 adsorption on them. This effect was minimized by activating 60NFO-40CTO backbones with different catalysts, being characterized by EIS under CO2&SO2 conditions. This improvement was later confirmed when performing permeation tests. Permeation was improved notably by reducing membrane thickness, depositing composite membranes on LSCF porous substrates.
La presente tesis trata sobre el desarrollo de membranas cerámicas para la producción de O2, así como de su uso en distintas aplicaciones industriales (producción de energía, industria química). Se han considerado distintos tipos de materiales tales como perovskitas (BSCF y LSCF), fluoritas (CGO) y materiales composites, así como distintas arquitecturas de membrana. y activación catalítica para optimizar la permeación y la selectividad/rendimiento en reacciones químicas. Para el BSCF se estudió la influencia del espesor y el uso de soportes porosos en la permeación de O2, con una mejora para las membranas más finas, y también el papel de los soportes porosos, contribuyendo con una resistencia adicional en el proceso de permeación. El estudio permitió también conocer más en profundidad los procesos que afectan a los distintos tipos de membranas, y establecer un modelo de permeación para membranas. Se recurrió a la activación catalítica mediante la adición de capas porosas de BSCF, obteniendo así mejores resultados para las membranas con capas en ambos lados. El concepto de membranas de BSCF activadas superficialmente se consideró también para la producción de C2H4 a partir de la deshidrogenación oxidativa de etano (ODHE), obteniendo rendimientos de C2H4 muy elevados. Membranas de BSCF con geometría tubular fueron caracterizadas para aplicaciones de producción de O2 y C2H4 mediante acoplamiento oxidativo de metano (OCM). Se consideró al LSCF para su uso en aplicaciones con atmósferas conteniendo CO2. Se desarrollaron membranas soportadas en soportes porosos de LSCF mediante tape casting y freeze-casting, realizando completos estudios de permeación, además de estudiar el tipo de soporte poroso ofreciendo menos resistencia a la difusión de los gases. Pese que para ambos tipos de membranas se obtuvieron muy buenos flujos de oxígeno, incluso bajo condiciones de CO2, para el caso de membranas con soporte fabricado mediante freeze-casting se consiguieron mayores valores de permeación, optimizándolos incluso con la activación catalítica. Los materiales con estructura fluorita poseen alta estabilidad bajo condiciones de reacción (atmósferas reductoras) o cuando son expuestos a CO2 (aplicaciones de producción de energía). Sin embargo, los valores de permeación suelen ser muy bajos. Se consideró una membrana de CGO-Co de 40 micras de espesor activada con nanopartículas de Pd para llevar a cabo un estudio de sus propiedades para la producción de O2, su comportamiento en contacto con CO2 y con atmósferas conteniendo CH4. La buena estabilidad demostrada y la mejora sustancial de los flujos de O2 bajo ambientes reductores, hacen que este tipo de materiales posean propiedades prometedoras para aplicaciones de oxicombustión y reacciones químicas. Se realizó un estudio con materiales composites formados por NFO-CTO. Una evaluación del contenido en CTO y su relación con la permeación de O2, resultó en mayores valores para composiciones con mayor contenido en CTO. Un composite consistente en 50NFO-50CTO se consideró para la realización de tests bajo condiciones de oxicombustión, con presencia de SO2. Pese al notable descenso en los flujos de O2, el material resultó ser completamente estable tras una exposición continuada al SO2. Un amplio estudio del efecto del CO2 y del SO2 sobre las reacciones superficiales se realizó mediantes medidas de EIS en electrodos de 60NFO-40CTO, demostrando que el SO2 afecta significativamente a las reacciones superficiales mediante procesos de adsorción competitiva en los centros activos. Se minimizó el efecto del SO2 sobre las reacciones de intercambio superficial al activar las membranas con capas catalíticas porosas de 60NFO-40CTO con distintos catalizadores, confirmando posteriormente esta mejora en tests de permeación en las mismas condiciones. Así mismo, se optimizó notablemente la permeación de las membranas de 60NFO-40CTO reduciendo el espes
La present tesi tracta sobre el desenvolupament de membranes ceràmiques per a la producció d'O2, així com del seu ús en diverses aplicacions industrials (producció d'energia, indústria química). S'han considerat diversos materials tals com perovskites (BSCF i LSCF), fluorites (CGO) i materials composites, així com diferents arquitectures de membrana i l'activació catalítica per a millorar la permeació i la sel·lectivitat/rendiment de les reaccions químiques. Per al BSCF s'estudià la influència de l'espessor i l'ús de suports porosos en la permeació d'O2, amb una millora dels fluxos d'O2 per al cas de les membranes més fines, i també el paper dels suports porosos, els quals contribueixen afegint una resistència al procés de permeació. L'estudi també va permetre conèixer més en profunditat els processos que afecten als diferents tipus de membranes, i establir un model de permeació per a membranes. Es va recórrer a l'activació catalítica mitjançant l'adició de capes poroses de BSCF, obtenint així millors resultats per a les membranes activades a ambdós costats. El concepte de membranes de BSCF activades superficialment es va considerar també per a la producció d'etilè a mitjançant la deshidrogenació oxidativa d'età (ODHE), obtenint rendiments de C2H4 molt elevats. Membranes de BSCF amb geometria tubular van ser caracteritzades per a aplicacions de producció d'O2 i C2H4 mitjançant l'acoplament oxidatiu de metà (OCM). Es va considerar al LSCF per al seu ús en aplicacions amb atmosferes contenint CO2. Així doncs, es van desenvolupar membranes suportades sobre suports porosos de LSCF fabricats per tape càsting i freeze càsting. Es van realitzar estudis complets de permeació per a ambdós casos, a més d'estudiar el tipus de suport porós que ofereix una menor resistència a la difusió dels gasos. Malgrat que es van obtindré molts bons fluxos d'O2 per als dos tipus de membranes, inclús sota condicions amb CO2, per al cas de les membranes amb suport fabricat per freeze càsting es van aconseguir majors valors de permeació, sent inclús optimitzats amb l'activació catalítica. Els materials amb estructura fluorita destaquen per l'alta estabilitat sota condicions de reacció (atmosferes reductores) o quan són exposats a CO2 (aplicacions per a la producció d'energia). Malgrat això, els valors de permeació solen ser molt baixos. Es va considerar una membrana de CGO-Co de 40 micras d'espessor activada amb partícules de Pd per a realitzar un estudi sobre les seues propietats en quant a la producció d'O2, el seu comportament amb el contacte amb CO2 i atmosferes reductores contenint CH4. La bona estabilitat demostrada i una millora substancial dels fluxos d'O2 sota ambients reductors fan que aquest tipus de material presente propietats prometedores per a aplicacions d'oxicombustió i reaccions químiques. Es va realitzar un estudi sobre materials composites formats per NFO-CTO. Es va realitzar una avaluació del contingut en CTO i la relació amb la permeació, observant una millora de la permeació amb un major contingut de CTO. Un composite consistent en 50NFO-40CTO es va considerar per a la realització de tests de permeació en condicions d'oxicombustió amb presència de SO2. Malgrat el notable descens en els fluxos d'O2, el material resultà ser estable després d'una exposició continuada al SO2. Es mesurà l'efecte del CO2 i del SO2 sobre les reaccions superficials fent ús de la tècnica d'EIS en elèctrodes de 60NFO-40CTO. Demostrant que el SO2 afecta significativament a les reaccions superficials degut a una adsorció competitiva O2-SO2 als centres actius. Es minimitzà l'efecte del SO2 sobre les reaccions superficials al activar les membranes amb capes poroses de 60NFO-40CTO amb diferents catalitzadors. Aquestes capes van ser caracteritzades per EIS sota condicions de SO2, confirmant posteriorment la millora al realitzar tests de permeació. S'optimitzà notablement la perme
García Fayos, J. (2017). DEVELOPMENT OF CERAMIC MIEC MEMBRANES FOR OXYGEN SEPARATION: APPLICATION IN CATALYTIC INDUSTRIAL PROCESSES [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/86189
TESIS
Premiado

Ionic liquids (ILs) have gained considerable research attention as potential replacements for volatile organic chemicals (VOCs) based solvents due to their low vapour pressures and ability to be easily recovered and recycled. Research on ILs has revealed such novel properties as: high chemical and thermal stabilities, good gas solubilites, wide windows of electrochemical stability, good electrical conductivities, high ionic mobilities and immiscibilities with some organic solvents and water. The exploitation of these IL properties has expanded the application scope to include: analytics, catalysis, electrochemistry, nanotechnology, synthesis and separations. This thesis examined the use of ILs in the synthesis of metal nanoparticles (NPs) and molecular complexes, with their application in biphasic catalysis. Metal NPs were synthesized directly in imidazolium or phosphonium ILs, which act as a reaction solvent and an electrostatic NP stabilizer. ILs functionalized with a metal binding moiety (i.e. thiolate or phosphine), otherwise known as functionalized ILs (FILs), were also employed for the synthesis of NPs to enhance their stability by direct attachment of the IL moiety to the metal surface. Transition metal NPs embedded in an IL solvent provided highly effective and recyclable biphasic hydrogenation catalysts for the reduction of alkene and arene substrates. FILs were also employed as stabilizing species of molecular complexes used as biphasic hydroformylation catalysts of long-chain olefins. Important to all of these studies was the influence of the IL parameters (i.e. cationic headgroup, alkyl chain length, counter anion) on the properties of the metal NPs and molecular complexes (i.e. NP size, surface plasmon band, stability under catalytic conditions, catalytic activity and selectivity). ILs are shown to be a highly tunable class of compounds, which allow for control of the properties of metal species stabilized within an IL.
Les liquides ioniques (LIs) ont fait l'objet d'une attention considérable en tant qu'alternatives potentielles aux solvants à base de composés organiques volatiles du fait de leur faible pression de vapeur saturante et de la facilité avec laquelle on peut les récupérer et les recycler. La recherche sur les LIs a par ailleurs révélé de nombreuses propriétés telles que : une grande stabilité chimique et thermique, de bonnes solubilités pour les gaz, une large fenêtre de stabilité électrochimique, une bonne conductivité électrique, une bonne mobilité ionique et une immiscibilité avec certains solvants organiques et l'eau. L'exploitation de ces propriétés ont étendues le champ des applications pour comprendre : la chimie analytique, la catalyse, l'électrochimie, la nanotechnologie, la synthèse et la purification. Cette thèse traite de l'utilisation des LIs pour la synthèse de nanoparticules (NPs) métalliques et de complexes, ainsi que de leur utilisation en catalyse biphasique. Des NPs métalliques ont été synthétisées directement dans les LIs à base de cations imidazolium ou phosphonium. Ces LIs jouent le rôle de solvant et de stabilisants électrostatiques pour les NPs. Des LIs fonctionnalisés avec une espèce ligante (i.e. un thiolate ou une phosphine), appelés LIs fonctionnalisés (LIFs), ont été employés pour la synthèse de NPs pour améliorer leur stabilité par attachement direct du LI à la surface métallique. Les NPs de métaux de transition ainsi obtenues sont très actives en catalyse biphasique d'hydrogénation des alcènes et des arènes et recyclables. Les LIFs ont également été employés comme ligands pour des complexes moléculaires utilisés en catalyse biphasique d'hydroformylation des oléfines à longue chaine. Au centre de cette étude, les paramètres moléculaires des LIs (i.e. le groupement cationique, la longueur de la chaine alkyle, le contre-ion) se sont révélés influer sur les propriétés des NPs métalliques et des complexes moléculaires (i.e. la taille des NPs, leur bande plasmon, leur stabilité en condition catalytique, leur activité catalytique et leur sélectivité). Les LIs constituent une classe de composés hautement versatiles, qui permettent le contrôle des propriétés des espèces métalliques qu'ils stabilisent.

La reacció de hidrogenòlisis per l'obtenció de 1,3-propandiol (1,3-PD) a partir de glicerol requereix l'ús de cars metalls nobles y elevades condicions de reacció, tot i això, no s'ha d'oblidar el baix rendiment en 1,3-PD resultant. Glycidol, que pot ser obtingut per reacció directa de glicerol, va ser proposat com una alternativa per la síntesis de 1,3-PD emprant Ni i Cu com a catalitzadors. Per tant, l'objectiu principal d'aquesta tesis va ser la síntesi de saponites mesoporoses acides mitjançant matrius (sals d'amoni quaternàries o polímers) i microones, per finalment avaluar la seva activitat a la hidrogenòlisis de glycidol per l'obtenció de 1,3-PD i 1,2-PD. Les saponites mesoporoses amb la major àrea superficial (600 m2/g) i la major acidesa (0.89 mEq CHA/ g) van ser obtingudes portant a terme la síntesi en medi bàsic (pH 13), emprant surfactants i microones. Aquesta y altres saponites sintetitzades van ser utilitzades com suports en la preparació de catalitzadors de Ni, els quals van ser provats en la hidrogenòlisis de glicidol a diversos temps i temperatures de reacció. Respecte als catalitzadors de Ni suportats, el millor rendiment a 1,3-PD va ser obtingut amb catalitzadors suportats en saponites acides, amb un 40 % en pes de Ni a 453 K durant 1h. L'efecte de diversos modificadors (W, Mo, V i Re) va ser testat en la reacció catalítica, on el millor valor de rendiment en 1,3-PD (46 %) per una relació 1,3-PD/1,2-PD de 1,24 va ser obtingut emprant catalitzadors de Ni modificats amb Re a 393 K després de 4h. La presència de Cu en el catalitzador de Ni ( catalitzadors bimetàl·lics de Ni-Cu) també va tenir un efecte beneficiós en la formació selectiva de 1,3-PD.
La reacción de hidrogenólisis para obtener 1,3-propandiol (1,3-PD) a partir de glicerol requiere el uso de costosos metales nobles y elevadas condiciones de reacción. Aún así, no se debe olvidar el bajo rendimiento obtenido en 1,3-PD bajo estas condiciones. Glycidol, el cual puede ser obtenido por reacción directa de glicerol, fue propuesto como una alternativa para la síntesis de 1,3-PD utilizando Ni y Cu como catalizadores. Por lo tanto, el objetivo principal de esta tesis fue la síntesis de saponitas mesoporosas ácidas mediante moldes (sales de amonio cuaternarias o polímeros) y microondas, para finalmente evaluar su actividad en la hidrogenólisis de glicidol para obtener 1,3-PD y 1,2-PD. Saponitas mesoporosas con la mayor área superficial (600 m2/g) y la mayor acidez superficial (0.89 mEq CHA/ g) fueron obtenidas llevando a cabo la síntesis en medio básico (pH 13), usando surfactantes y microondas. Esta y otras saponitas sintetizadas fueron utilizadas como soportes en la preparación de catalizadores de Ni, los cuales fueron testados en la hidrogenólisis de glycidol a diferentes tiempos y temperaturas de reacción. Respecto los catalizadores de Ni soportados, el mejor rendimiento hacia 1,3-PD fue obtenido con catalizadores soportados en saponitas ácidas, con un 40 % en peso de Ni y a 453 K durante 1h. El efecto de varios modificadores (W, Mo, V y Re) fue testado en la reacción catalítica, donde el mejor valor de rendimiento hacia 1,3-PD (46%) con un ratio 1,3-PD/1,2-PD de 1,24 fue obtenido utilizando catalizadores de Ni modificados con Re a 393 K después de 4 h. La presencia de Cu en el catalizador de Ni (catalizadores bimetálicos de Ni-Cu) también tubo beneficios en la formación selectiva de 1,3-PD.
The direct hydrogenolysis of glycerol to 1,3-propanediol (1,3-PD) requires expensive noble metal catalysts, harsh reaction conditions and even then, the yield to 1,3-PD is moderate to low. Glycidol molecule which could be obtained from glycerol was proposed as an alternative substrate for the synthesis of 1,3-PD using cheap transition metal Ni and Cu catalysts. Hence, the main objective of the thesis was to prepare mesoporous acid saponite using template and microwaves and evaluate its activity in the hydrogenolysis of glycidol to 1,3-PD and 1,2-PD. The highest surface area (600 m2/g) mesoporous saponite with high surface acidity (0.89 mEq. CHA/ g) was obtained when the synthesis was carried at pH 13, using surfactant and in microwaves. This and other saponites were used in the preparation of supported Ni catalysts and their activity was tested at different reaction temperature and time. Among the supported Ni catalysts, the best 1,3-PD yield was obtained using Ni catalyst supported at 40 wt % on the mesoporous saponite and when the reaction carried out at 453 K for 1h . The effect of various modifiers (W, Mo, V and Re) on this catalyst was tested and the best result was obtained in case of Re modified Ni catalysts which afforded 1,3-PD at 46% yield with 1,3-PD/1,2-PD ratio of 1,24 at 393 K and after 4 h. The presence of small amount of Cu in Ni-Cu bimetallic catalysts was also found beneficial for the selective formation of 1,3-PD.

There is an ongoing interest in the use of metal oxides as regenerable sorbents for the removal of sulphur dioxide from flue gases. Cerium oxide on alumina has been suggested but few experimental data are available, particularly for the regeneration process. It has been shown that the overall stoichiometry of regeneration with hydrogen can be split into twelve reaction steps. These were deduced from an inspection of rate data and analysis of partially reduced samples by volumetric methods and using Fourier transform infra red spectroscopy. Below about 828 K, the hydrolysis of intermediate sulphides is rate limiting whilst, above that temperature, it is the formation of sulphides and/or the reduction of oxysulphates to cerium oxide which are important. The sulphation process has been investigated in the range 695 - 880 K. Observed reaction rates were interpreted both in terms of simple rate laws and using an adsorption/reaction mechanism. The latter was shown to be the most satisfactory for describing the reaction giving an activation energy of 46.5 kl/mol. The original diffuse - interface model for gas solid, non - catalytic reactions has been presented in dimensionless form and applied to reactions with various orders. This model was discussed in relation to the sharp - interface model. The effects of assuming different concentration profiles within the reaction zone were examined. Initial assumptions regarding the distribution of reactants in the reaction zone - whether linear or sigmoidal had little affect on the predictions of zone thicknesses and gaseous concentration profiles. No such agreement was found when exponential profiles were assumed. A new grain model has been developed in which it is assumed that a diffuse reacting interface, rather than a sharp - interface exists within the grains. Model equations were solved numerically and the effect of various reaction parameters on model predictions investigated. Some of the simplified techniques used previously to solve the grain model have been extended to the new model. A comparison of these with the numerical solution differed by a maximum of 12 %. Data relating to the regeneration in hydrogen of cerium sulphate on alumina, and also for the better known reaction with sulphur dioxide of copper oxide on alumina were analysed using the diffuse - interface shrinking core model and, for comparison, the volume reaction model. Both models provide a fairly good fit of the regeneration data. Energies of activation are in the range 190 to 210 kJ/moI. Both models fit data on the sulphation of copper oxide on alumina with reasonable accuracy with energies of activation ranging from 28 to 31.6 kJ/mol.

Mon travail de thèse porte sur l’étude de la réaction catalytique d’oligomérisation avec des complexes de nickel, fer et cobalt coordinés par des ligands de type N-O, P-N, N-P-N, P-O et P-N-P avec le donneur N représenté par un hétérocycle oxazoline ou pyridine. Ces complexes, activés par des cocatalyseurs MAO ou AlEtCl2, ont montré de fortes activités et une grande sélectivité pour les oléfines C4 en oligomérisation de l’éthylène. Les complexes de nickel à chélates P-N ont montré l’importance des substituants du phosphore sur la sélectivité des oligomères formés. Par ailleurs, les études cristallographiques sur les complexes de nickel coordinés par des ligands type N-O et P-N ont montré la formation de complexes mono-, di- et tétranucléaires. Les complexes de cobalt, fer et palladium avec des ligands N-P-N ont mis en évidence des modes de coordinations originaux de type N-N, P-N ou N-P-N des ligands dépendants des substituants du ligands et du centre métallique
My Ph-D thesis concerns the study of the catalytic oligomerization reaction with nickel, iron and cobalt complexes coordinated by N-O, P-N, N-P-N, P-O and P-N-P type ligands with a N donor atom represented by an oxazoline or a pyridine heterocycle. These complexes activated by a cocatalyst such as MAO or AlEtCl2 showed high activities and a high selectivity of C4 olefins in ethylene oligomerization. The nickel complexes with P-N chelates showed a high impact of the P substituents on the oligomerization selectivities. Moreover, the crystallographic studies on nickel complexes coordinated by N-O and P-N type ligands showed the formation of mono-, di- and tetranuclear complexes. The cobalt, iron and palladium complexes with N-P-N ligands highlighted original N-N, P-N or N-P-N coordination modes of the ligands influenced by the ligand substituents and the metal center

The main body of this thesis comprises four chapters: Chapter One serves as an introduction. The first two thirds deals with cell signalling cascades, focusing particularly upon protein kinases and the roles that their dysfunction play in cancerous processes and upon the methods employed to inhibit them in a bid to counter these processes. Kinase inhibition by small molecules is a very active area of research and notable clinical successes have been achieved. The last portion of the chapter addresses some of the issues surrounding .drug discovery, and ends by stating the author's intention to utilise novel transition metal catalysis to access potential anticancer compounds, to test these compounds against cancer cell lines in vitro and to study their interactions with the active sites of cell signalling proteins known to be mutated in these same cancers in silica. After a brief introductory section dealing with relevant chemistry, Chapter Two describes the author's work with the arylallylation of purine derivatives via a 3-component palladium-catalysed cascade developed within the Grigg group, and the subsequent in vitro testing against the colon cancer cell line HCT116. Four of the synthesised compounds showed <10 uM IC50's. Chapter Three gives an account of the invention of a novel 3-component cascade synthesis of diindolylmethane compounds, three of which have demonstrated selectivity and < 10 uM activity against the LNCaP prostate cancer cell line in vitro. Derivatives of two of these. compounds in turn show enhanced selectivity and 0.5 - 2 uM activity against the LNCaP and PC3 prostate cancer cell lines. A short review of the relevant chemistry is given at the beginning of the chapter. Chapter Four furnishes full experimental details of the work carried out, together with appropriate data.

Els compostos organoborats son altament utilitzats en un extens nombre de camps, des de la medicina, en la teràpia de captura neutrònica en bor o altres molècules amb activitat biològica, fins a l’ús de molècules funcionals com els polímers. Nosaltres hem centrar la nostra atenció a l’ús dels compostos organoborats com intermedis de síntesis per a productes d’alt valor afegit. El tema principal d’aquesta tesis es el desenvolupament de noves metodologies sintètiques per la obtenció de compostos organoborats de manera eficient. Ens hem centrat bastant en la síntesis de compostos carbonílics -borats, com a sintons per la síntesis de molècules difuncionals. Em estudiat la addició de bor a molècules insaturades des de dos estratègies diferents: la addició catalítica de bor mitjançant metalls de transició i sense metall. Sempre ficant especial énfasis en la versió quiral de la reacció.
Organoborane compounds are highly used in a huge number of fields, from medicine, in the boron neutral capture therapy or other molecules with biological activity to the use of functional molecules such us polymers. In our case, we focused our atention in the use of organoborane compounds as a intermediates for the synthesis of high value products. The main topic of this thesis is develop new synthetic methodologies for the efficient obtaition of organoborane compounds. We focus in the synthesis of -boryl carbonyl compounds as a synthons for the synthesis of difuncional molecules. We studied the boron addition to unsaturated molecules in to main strategies: the boron addition using transition metal catalyst or without metal. Always with special attention for the chiral approach of the reaction.

The objective of this research was to aid in the development of a new method for removing and destroying soil contaminants. In particular, 1,2,4,5-tetrachlorobenzene (TeCB) was selected for this research. Hydrodehalogenation (HDH) was paired with hydrogenation for remedially destroying TeCB without generating a secondary waste stream in a single batch reactor. Palladium- and rhodium-catalyzed HDH and hydrogenation were applied in a batch reactor at room temperature and moderate hydrogen pressure. Cyclohexane was formed as an end product with benzene as an intermediate reactant. An analytical method was developed to measure TeCB, benzene, and cyclohexane in a solution of water and ethanol, 50:50 by volume before mixing, by gas chromatography with electron capture detection (ECD) and flame-ionization detection (FID). Experimental data were consistent with a model in which dehalogenation and hydrogenation were considered sequential processes with first order reaction kinetics.

Chemical reactions can have a staggering amount of molecular complexity. Reaction mechanisms have been proposed with over one hundred elementary reaction steps that occur in the same system simultaneously. While several methods exist to simplify and make sense of the pathways and kinetics via which these reactions proceed, e.g., reaction graphs, sensitivity or flux analysis, microkinetic analysis, and comparison of energy landscapes, etc., these methods all have limitations and are often not able to capture a comprehensive picture of the kinetics of system. It has been found useful to view these mechanisms as a network, i.e., a reaction graph. These graphs enable the visualization of the pathways of the reaction and can provide an analytical tool for pathway and kinetic analysis. However, many of the specific graph-theoretic approaches in the literature are not the most suitable for kinetic analysis of complex mechanisms; as they are simply not based on rules that are rigorous enough to fully enumerate all the pathways or provide quantitative analysis of the reaction rates. Our Reaction Route (RR) Graph approach is different in that it depicts the mechanism by a graph that is consistent with all physical and chemical laws associated with reaction networks, particularly being consistent with mass and energy conservation, i.e., Kirchoff’s Flux Law (KFL) and Kirchoff’s Potential Law (KPL). Because of their adherence to these laws, RR Graphs are able to provide an accurate graph-theoretical tool not only for depicting all reactions routes as walks (hence the name RR Graph) but also for pruning mechanisms and allowing a simplified but accurate quantitative description of reaction rates. This adherence to KFL and KPL does mean that the construction and implementation of these graphs can be prohibitively difficult for large mechanisms. For large reaction systems,especially nonlinear mechanisms, it is not realistic to generate these graphs by hand. And although there exists an analytical solution to find a determinant matrix for the RR Graph of a mechanism, the process involves an exhaustive search for a solution which experiences a combinatorial explosion as the number of steps gets very large. This leads to the idea of developing an algorithm for a computer program that can determine how to generate these graphs automatically. Unfortunately, the same combinatorial explosion is present such that for a moderately sized twenty step mechanism, it could take an average computational processor over a decade to find a solution. We have determined, however, that this brute force combinatorial approach can be avoided if heuristics could be developed to bridge gaps in our knowledge of how these graphs are constructed. Thus, developing a better analytical approach and/or a tighter set of heuristics for a computer algorithm are the overarching goals of this work. To make progress toward developing such heuristics, a set of microkinetic mechanisms were analyzed with the notion that the realization of the RR Graphs would highlight a better approach to their construction and usage. In particular, a very large linear reaction system, a smaller linear system and two non-linear reaction systems were analyzed to develop insights into how each graph is manually constructed and analyzed. Furthermore, kinetic analysis was done for these mechanisms and compared to experimental data and other analytical tools to prove not only the validity of the RR Graphs, but also how they are a significant improvement over more commonly used approaches for mechanistic and kinetic analysis. Based on the lessons learned through a consideration of these examples, a set of heuristics are established and enumerated with the ultimate goal of developing an intuitive algorithm that can help automate drawing and kinetic analysis via RR Graphs of complex mechanisms.

Les surfactifs catalytiques équilibrés (baptisés "Catasurfs") permettent d'élaborer des systèmes de microémulsions polyphasiques utilisés comme milieux réactionnels. Dans ce contexte, des alkylammonium et des alkylsulfonates amphiphiles bicaténaires ont été développés. Leurs comportements en système aqueux (solubilité, concentration micellaire critique, diagramme binaire, cristaux liquides) ainsi qu'en système biphasique eau/huile (diagramme en poisson, formation de systèmes de microémulsions) ont été étudiés en fonction de la nature des contre-ions. Les phases cristallines lyotropes ont été identifiées par microscopie optique à polarisation et par diffusion des rayons X aux petits angles (SAXS). Une classification des surfactifs selon leur amphiphilicité a été établie à partir des diagrammes de Fish construits selon un balayage en huiles. Le comportement de phases de ces surfactifs dans l'eau (micelles) et en système biphasique eau/huile (microémulsion) dépend non seulement de la longueur de la chaîne mais aussi du degré d'hydratation des contre-ions, en accord avec la série d’Hofmeister. L’intérêt des microémulsions polyphasiques à base de Catasurfs a été démontré d'une part en microémulsion Winsor III à base de [DiC10]2WO4 appliquée à l'époxydation des oléfines et à l’oxydation de sulfures en présence de H2O2 et d'autre part, via l'élaboration de microémulsions Winsor IV thermosensible utilisant la synergie entre les C8E4 et [DiC8]2MoO4 pour la "Dark Singlet Oxygenation". Par ailleurs, une nouvelle voie de synthèse « one-pot» de la (+)-nootkatone, fragrance à haute valeur ajoutée, à partir du(+)-valencène a été mise au point dans conditions sans solvant
Balanced Catalytic Surfactants (abbreviated as “Catasurfs”) allow the design of multiphase microemulsion systems used as reaction media. In this context, the double tailed alkylammonium and alkylsulfonate amphiphiles have been developed. Their behavior in aqueous system (solubility, critical micellar concentration, binary diagram, lyotropic liquid crystal) as well as biphasic oil/water system (Fish diagram, forming microemulsions systems Winsor Type I, II, III and IV) were studied based on the nature of counter ions (Br, Cl, WO42−, MoO42−, SO42− for anionic and H+, Li+, Na+, K+, Cu2+, Zn2+, Ca2+, Sc3+ for cationic). Lyotropic crystal phases were identified by polarization optical microscopy and small angle X-ray scattering diffusion (SAXS). A classification of surfactants according to their amphiphilicity was established from the Fish diagrams constructed by scanning oil polarities. The phase behavior of these surfactants in water (micelles) and biphasic oil / water system (microemulsion) does not only depend on the alkyl chain length but also the counter ions hydration degree, in agreement with the Hofmeister series. The advantages of multiphase microemulsions based on “Catasurfs” were on one hand demonstrated by the epoxidation of olefins and oxidation of sulfides in a Winsor III microemulsion based on [DiC10]2WO4 in the presence of H2O2 and, on the other hand, by the development of a thermosensitive Winsor IV microemulsions using synergy between C8E4 and [DiC8]2MoO4 for “Dark Singlet Oxygenation”. In addition, a new “one-pot” synthetic route of the (+)- nootkatone, a high value-added fragrance, from the (+)-valencene was developed under solvent-free conditions

碩士
臺灣大學
化學研究所
98
In this work, three-dimensional branched Au nanomaterials were produced at high yield by reacting an aqueous solution of sodium tetrachloroaurate with a tea extract at ambient temperature and pressure. By varying the tea concentrations at a constant amount of sodium tetrachloroaurate, different size and shape of Au nanomaterials were separately prepared. We also synthesized other noble metal nanoparticles such as Ag, Pt and Pd by tea extract. UV-vis absorption, energy dispersive X-ray, X-ray diffraction, and transmission electron microscopy measurements were conducted to characterize the as-prepared Au nanomaterials. The results revealed that the branched Au nanomaterials (50 nm) were formed through the self-assembly of short nanorods (8 nm in width and 12 nm in length). According to the experiments, we find out that the polyphenols in tea extract play an important role of reducing Au3+ ion to Au and stabling the branched Au nanomaterials. By conducting Raman measurements, we found that the branched Au nanomaterials was useful on enhanced signal further than 10 times through surface-enhanced Raman scattering (SERS) effect and Ag nanoshells when adopting 4-mercaptobenzoic acid as report. We believe the Au/Ag nanomaterials have the potential to be good SERS substrates because of the stable signal and clean surface. Through the interaction of polyphenol and Titanium metal (ligand to metal charge transfer), the branched Au nanomaterials were easily deposited on the surface of TiO2 nanomaterials. On the photocatalysis, we have found the photodegradation of the methylene blue is further enhanced in TiO2(P25) about 2.50 folds and TiO2(P210) about 2.05 folds through the deposition of the branched Au nanomaterials. Consequently, we believe the branched Au materials have the potential to be good SERS substrates and photocatalysis enhancers because of the stable signal and clean surface.

碩士
長庚大學
化工與材料工程研究所
92
Traditionally, oxidation processes are used for the conversion of chemicals for chemical syntheses or removal of VOC for pollution abatement. In this presentation we report our new discovery of a super reactive oxidation catalyst, Pt/BN/support, for rapid generation of heat by the catalytic combustion of methanol or n-hexane from room temperature up to 500-1000OC in a matter of 3 to 10 min. Moreover, the waste gas showed no trace amount of NOx pollutant by mass spectrometer. Vapor phase combustion by a conventional furnace often losses over 60% of heat to chimney and produce noxious NOx pollutants. Therefore, application of this catalyst provides a high efficient heating device and avoids air pollution during heating process. The Pt/BN catalysts were prepared by incipient wet technique by impregnating 3.7wt% of platinum on a boron nitride support. The Pt/BN catalyst was then deposited on five time weight ofγ-alumina support or commercial Pt-catalysts. The catalyst remains active over a 136.5-hours test. In a steel pipe ( 12.7 mmIDx mmL), 12gm of this oxidation catalyst was placed and insert a catalyst tube ( 25.4 mmODx mmL) containing 120gm of CuOZnO steam reforming catalyst (G66* of Sud Chemie Catalyst Japan, Inc.); air (2L/min) and methanol (0.32gm/min) were introduced at room temperature. In 35 min., the reactor system was heated up to 535 OC; the result is good for the reaction of high supply energy.

博士
國立清華大學
化學系
87
The catalytic applications of V(IV) and V(V) ions in organic transformations have been discussed. The thesis is divided into three parts. In the first part VO(acac)2 and VO(salen) catalyzed oxidations in the presence of molecular oxygen have been presented. The oxidative coupling of 2-naphthol to BINOL, phenol and its derivatives to the corresponding biphenols and the oxidation of p-hydroquinones to p-quinones were carried out successfully in good yields. However, selectivities in the asymmetric coupling reactions were not up to the expected level. The conditions have to be improved for better selectivities. The synthesis of a series of tridentate ligands 100-108 from camphor and their vanadium complexes for asymmetric oxidation of sulfide to sulfoxide have been described in Part 2. The best results were obtained when the ligand 105 was used. The maximum optical induction (66 %) was achieved for the oxidation of sulfide 113 to sulfoxide 118. In Part 3, VO(acac)2 was used to activate tertiary amine N-oxide by generating iminium ion for subsequent nucleophilic addition to form C-C bond. This methodology was applied in Mannich reaction and the synthesis of a-arylamines and a-cyanoamines.

碩士
國立臺灣大學
化學研究所
99
Abstact We have successfully prepared and characterized dinuclear nickel and copper complexes containing 2,7-di(R2-pyrazolyl)-1,8-naphthyridine (La R = H, Lb R = Me, Lc = Ph) and have studied the application in this thesis. Reaction of La ~Lc with NiCl2 provided the dinickel complex [(Lx)Ni2Cl4(CH3OH)2] (X = a~b) (5a~5b). X-ray crystal determinations show that this series of nickel complexes are six coordinate. Treatment of sodium trifluoroacetate with 5a resulted in the formation of trifluoroacetate substituted species, which was characterized by UV, IR and mass spectroscopy. Treatment of La and Lb with [Cu(CH3CN)4PF6] yielded the dinuclear copper complexes [(Lx)Cu2(CH3CN)4]．2PF6 (x = a, b) (7a~7b), which were heating in the co-solvents (acetone/chloroform) in the presence of chloride resulted in the formation of [(Lx)Cu2Cl2] (x = a~c) (8a~c). For the synthesis of iridium complex via the treatment of La with IrCl3．3H2O yielded [[(La)Ir(H2O)Cl3], a mono-nuclear species. X-ray structural characterization showed that mononuclear iridium complex is the six coordinate structural.In the catalytic application, dinuclear nickel complexes do show the activity on the oxidative homo-coupling of the terminal alkynes. Complex 5a and 5c afforded the corresponding 1,3-diyne product with good yields with dioxygen as the oxidant under mild conditions (35oC).

碩士
國立中正大學
化學暨生物化學研究所
106
Palladium is usually used as catalyst for carbon-carbon coupling reactions, such as Heck reaction, Suzuki reaction, etc. Palladium is expensive and has a good catalytic effect for carbon-carbon coupling reactions. However, it is hard to be recycled. In order to make palladium easier to be recycled after catalytic reactions, we tried to add iron to make magnetic iron-palladium (FePd) nanoparticles, which was easy to be recycled by magnets. In this study, we have employed Fe(CO)5 and Pd(acac)2 as the metallic precursors. By using a variety of procedures, reaction temperature, surfactants and ratio of surfactants, we sucesssfully synthesized different sizes of magnetic FePd nanoparticles. When we used magnetic FePd nanoparticles which we synthersized as catalyst for Heck reaction, we found that when the concentration of catalyst was 0.025 mole percentage and reaction time was 1 hour, we had the best catalytic efficiency with TOF value of 1369.60. Excessive concentration of catalyst and reaction time could not promote TOF value. The morphology of FePd magnetic nanoparticles were characterized by transmission electron microscopy (TEM). The structures and contents of FePd magnetic nanoparticles were analyzed by powder X-ray diffraction (PXRD), energy dispersive X-ray spectroscopy (EDS) and atomic absorption spectroscopy (AA). In addition, we measured the saturation magnetization and coercivity by vibration sample magnetpmeter (VSM). At last, we analyzed the products of Heck reaction using magnetic FePd nanoparticles as catalyst by gas chromatography (GC) and nuclear magnetic resonance (NMR).

碩士
嘉南藥理大學
環境工程與科學系
103
Abstract The purpose of this study is focus on the preparation of membrane contactor and applied for catalytic ozonation of phenolic effluents. The membrane contactor were prepared by coating iron and copper oxides on the ceramic support with wash-coat technology. The raw wash-coated membranes were activated by caicinating process in the suitable conditions. The activated membrane contactor were applied for the catalytic ozonation of phenol in aqueous soultion and valuated the comversion and TOC degredation of reaction. The oxidation process were attempted to connect with bio or chemical process in the wastewater treatment for the water resued considerartion. The iron nitrate and copper nitrate were used as the active metal sources in preparation of membrane contactor. The support materials were used the microporous alumina oxides tube. The composition of washcoat solution were preparaed with active metal salt and ethanol at 85C. After the washcoat material is well dissolved in the ethanol, the creamic tube was dipped in the solution and dry in the air for further activating the coated ceramic tube in the oven under the specfic conditions. The oxidation performance were valuated by the phenol conversion and TOC removal of oxidation. Based on the results of this study, the catalytic oxidation performance were promoted under the basic environment and the copper type membrane reactor was superior than the iron type in all tests. The completely conversion of phenol and over 40% TOC removal was achieved in 2 hours ozonation with 500 mg/L phenol at room temperature. All the tested samples showed that pH strong affect the free radical generation and oxidation performance of phenol in this study. The competition of ozone decomposition and catalytic ozonation dominated the performance of ozonation. The basic condition is bentifited to the catalytic ozonation mechanism in the investigation. After the life time test, it is indicated that membrane contactor presented the same ozonation performance after 5 times reused and over 99% phenol conversion can be also achieved in this study.

博士
國立清華大學
生醫工程與環境科學系
100
The Au-Fe3O4 hybrid materials, especially dumbbell-like and flower-like nanoparticles, have been demonstrated to be a potential nanocomposite for various applications because of their enhanced physicochemical properties. In this study, an effective process for the synthesis of different morphologies of Au-Fe3O4 heterostructures and other M-Fe3O4 heterostructures (M= Ag, Pt, Pd) has been developed, and the effects of different morphologies of Au-Fe3O4 heterostructures on MRI/sensing and catalysis are systematically studied. The monodisperse and size-tunable magnetic Fe3O4 and Au nanoparticles (NPs) were first synthesized and optimized. The diameters of as-synthesized Fe3O4 NPs decrease upon increasing concentrations of iron oleate complex and oleic acid/oleylamine, while the sizes of Au NPs decrease with the increase in reaction temperature. The Au-Fe3O4 heterostructures are successfully fabricated by thermal decomposition of iron oleate-complex in the presence of Au seeds through a seed-mediated growth process. Different morphologies of Au-Fe3O4 heterostructures can be easily controlled by adjusting the amount of iron oleate-complex, size of Au seeds, duration, and solvent amount. The dumbbell-like and flower-like Au-Fe3O4NPs can be synthesized using 5 nm and 10 nm Au NPs as seeds, respectively. These heterostructures show a red-shift in surface Plasmon resonance band and enhanced magnetic property. In addition, other noble metal–iron oxide nanoparticles including Ag, Pt and Pd are successfully produced using the same synthesis procedure. The structural and electronic properties of epitaxial linkage in Au-Fe3O4 heterostructures were investigated by X-ray absorption spectroscopy (XAS). After conjugation with iron oxides, the d-hole population of Au NPs increases, indicating a charge transfer from Au to Fe3O4. In addition, the increase in Fe2+ valence state was observed in Au-Fe3O4 heterostructures, which gives the strong evidence on supporting the hypothesis of the charge transfer between Au and Fe3O4. The theoretical simulation of XAS further demonstrates the presence of Au-Fe bonding in the Au-Fe3O4 heterostructures and confirms the epitaxial linkage relationship. The dumbbell- and flower-like Au-Fe3O4 heterostructures were further used as magnetically recyclable catalysts for 4-nitrophenol and 2,4-dinitrophenol reduction. The heterostructures exhibit bifunctional properties with high magnetization and excellent catalytic activity towards nitrophenol reduction. The pseudo-first-order rate constants for nitrophenol reduction are 0.63-0.72 min-1 and 0.38-0.46 min-1 for dumbbell- and flower-like Au-Fe3O4 heterostructures, respectively. In addition, the heterostructured nanocatalysts show good separability and reusability which can be repeatedly applied for nearly complete reduction of nitrophenols for at least 6 successive cycles. The reaction mechanism for nitrophenol reduction by Au-Fe3O4 nanocatalysts is also proposed and confirmed by XPS and FTIR analyses. In addition, several environmental parameters including the initial nitrophenol concentration, pH, and temperature were optimized for the reduction of 4-trophenol. The kinetic data of nitrophenol reduction could be well-described by the Langmuir-Hinshewood model with the activation energy of 26.3 kJ mol-1, clearly indicating the nature of surface-mediated reactions. The catalytic reduction of 4-nitrophenol was also examined at various pHs and found that higher pH value retards the hydrolysis rate of borohydride, resulting in lower catalytic efficiency on nitrophenol reduction. Different morphologies of Au-Fe3O4 heterostructures were further used as potential contrast agent for magnetic resonance imaging (MRI). Since the particle surface coated with a dense organic molecules, 8-armed PEG-Amine were chosen as surface modification agent for phase transfer and bio-functionalize. The water-dispersed Au-Fe3O4 heterostructures were then used as MRI contrast agents, and r2 values of different morphology of NPs were 142.9, 124.1, 112.9, 127.7 mM 1s-1, respectively, for Fe3O4 NPs, 5 nm Au dumbbell-like NPs, 10 nm Au dumbbell-like NPs, and 10 nm Au flower-like NPs. In addition, the Au domain in the heterostructures can serve as optical probe to sense the tau-protein via hybridization-mediated aggregation. The developed nanosensor displays a linear range (0.5-50 ng/mL) with detection limit of 3 ng/mL for tau protein detection. The results obtained in this study clearly demonstrate that the Au-Fe3O4 heterostructures are multifunctional materials which can serve as an ideal platform to apply in the fields of various heterogeneous catalytic processes and biomedical diagnosis.

碩士
國立臺灣大學
化學研究所
101
Abstract We have successfully prepared a multidentate ligand 2,7-di(2,2′-dipyridylamino) -1,8-naphthyridine (4), and its ruthenium dinuclear complexes. The use of the prepared ruthenium complex as the catalyst for the cycloaddition of o-phenylenediamine with ethyleneglycol was investigated. For the ligand synthesis, the coupling reaction of C-N bond between 2,7-di- chloro-1,8-naphthyridine (3) and 2,2′-dipyridylamine yielded 4, which has six coordination sites for the metal. Coordination of 4 with [(η6-p-cymene)RuCl2]2、[Cu(CH3CN)4PF6]、 CuI and CuBr resulted in a dinuclear ruthenium and dicopper complexes [(4)Ru2(η6-p-cymene)2(Cl)2(PF6)2] (5a)、[(4)2Cu2(THF)2(PF6)4] (5b)、 [(4)Cu2I2] (5c) and [(4)Cu2Br2] (5d), respectively. Complexes of 5a and 5b were characterized by X-ray crystals. We had found that 5a is a hexa-coordination complex, and 5b is a five-coordination complex. Complex 5c and 5d were characterized by ESI-MASS. Complexes 5c and 5d are four-coordination complexes with iodine and bromine as the bridging ligand, respectively. In the catalytic application, tests of the dinuclear ruthenium complex (5a) as catalyst for the cycloaddition reaction of o-phenylenediamine with ethyleneglycol were performed. With oxygen as the oxidant, reaction of o-phenylenediamine with ethylene glycol and ethanolamine with the use of 5a as the catalyst afforded the corresponding quinoxaline in good yields.

碩士
國立交通大學
環境工程所
89
Catalytic incineration is one of the VOCs control techniques that has the advantages of high efficiency and complete oxidation. There were two types of models currently used for the design and improvement of catalytic incineration process, the lumped parameter model and the mass transfer model. However, their applications and limitation have not been compared and studied. In this study, a two-dimensional mass transfer model and one-dimensional effectiveness factor model were developed and their applications were compared. They were then used to design the catalytic incineration reactor and to analyze the effects of pore diffusion and external diffusion. An analytical solution of the two-dimensional mass transfer model was derived so that both models are simple and can be applied easily. The results indicated that two-dimensional analytic solution model has a better prediction in the VOCs removal efficiency and then can be applied to design the catalytic incineration reactor. Using the catalyst data in the literature, the design results showed that when the channel pitch is 0.35cm and temperature is 575°K, the space velocity has to be controlled to below 23000hr-1 for ensure 90% removal efficiency. As a result of comparison of the four VOCs, benzene, ethylbenzene, styrene and toluene, it found that the adsorptive capacity of benzene among the four is the smallest compound. The influence of pore diffusion on benzene destruction is the largest at higher temperatures while it is the lowest at temperature higher than 460°K. On the other hand, benzene is suffered most from external diffusion at high temperature.

碩士
國立臺灣大學
化學研究所
105
The use of bimetallic complexes as catalysts for the catalytic reactions has received much attraction due to the possible synergistic effect between the metal ions. In this study, a naphthyridine-based multidentate ligand 2,7-bis(2-pyridyl)-1,8-naphthyridine (bpnp) and an anthyridine-based ligand 5-phenyl-2,8-bis(2,2’-bipyridin-6-yl)-1,9,10-anthyridine (pbbpa) were synthesized. Coordination of bpnp with Pd(OAc)2 in a mixture of MeOH and trifluoroacetic acid yielded the dipalladium complex Pd2(bpnp)(TFA)3(OH) (9). Treatment of pbbpa with Pd(MeCN)2Cl2 followed by anion exchange resulted in the formation of [Pd2(pbbpa)Cl2](PF6)2 (11). The structures of both complexes were confirmed by 1H-, 13C-NMR and ESI-HRMS. In a previous work, the resulting complex obtained from treatment of 11 with NaBH3CN was catalytically active toward the reduction of nitroarenes in the presence of H2. In this work, complex 9 showed a similar activity without any pre-treatment. Comparison of the catalytic activity between these complexes was revealed. This catalytic system is applicable for various nitroarenes. The possible reaction mechanism of this catalytic system is established by the kinetic studies and the reactivity of possible intermediates under the catalytic conditions. 9 catalyzed through the condensation pathway, in which N-phenylhydroxylamine and nitrosobenzene formed azoxybenzene, and gave aniline by following reduction with the assistance of dimetal complex. On the other hand, 11 and Pd(bpy)(TFA)2 catalyzed through direct pathway, in which aniline was obtained by reduction of N-phenylhydroxylamine.

碩士
國立臺灣大學
化學研究所
102
This work involves the coordination study of multidentate dinucleating ligand 2,7-bis(3,5-dimethyl-1H-pyrazol-1-yl)-1,8-naphthyridine (4) with copper and ruthenium precursor and catalytic activity of the resulting dicopper complex. Reaction of 4 with [Cu(CH3CN)4]PF6 provided the dicopper complex [(4)Cu2(CH3CN)4].2PF6 (5).In addition, oxidation of 5 in acetic acid produced Cu(II) complex [(4)Cu2(CH3COO)3(OH)] (11). Coordination of 4 with CuBr and CuI resulted in the formation of dinuclear copper complexes [(4)Cu2Br2] (6) and [(4)Cu2I2] (7), respectively. Both 6 and 7 contain halides as bridging_ligands. Treatment of 4 with [Ru(benzene)Cl2]2 afforded the mononuclear ruthenium complex [(4)Ru(benzene)Cl2] (8). All complexes were characterized by spectroscopic methods. Structure of ruthenium complex 8 was further confirmed by X-ray crystallography. In the catalytic application, dinuclear copper complexes were active for the oxidative homocoupling of the terminal alkynes under basic conditions. In the presence of base and complex 5, terminal alkynes underwent homocoupling to afford the corresponding symmetrical 1,3-diynes in moderate to good yields with dioxygen as the oxidant under mild condition. Comparison of activities of metal complexes including Cu(II) were investigated.

碩士
國立臺灣大學
化學研究所
97
2.6-bis[bis(2-pyridylmethyl)-aminomethyl]-4-methylphenol(Hbpmp) is a special ligand which containing two tri-dentate nitrogen binding sites, and can form bimetallic complexes with various metals. Until now, there are no catalytic applications of its metal complexes on catalysis, but only crystallography and characterization on the bimetallic species. It is expected that the two metal centers will have complementary interaction between each other. In this work, we have prepared the Pd(II)-Pd(II) complex and its catalytic application. The Pd(II)-Pd(II) complex could be formed by addition of PdCl2(PhCN)2 to Hbpmp in a dichloromethane solution. Upon recrystalization in a mixed EA and methanol solution, the desired complex was obtained in pure form, which was characterized by spectroscopic and X-ray structural analyses. Hbpmp can be prepared by using bis-(2-pyridylmethyl)amine and 2,6-bis(bromomethyl)-4-phenol undergo the nucleophilic substitution in THF solution. This Pd(II)-Pd(II) complex catalyzed the Suzuki coupling by a low-loading amount of catalyst, in water and short reaction time with great yields.