The study of catalysis is a fundamental aspect of chemical engineering, as its implications affect all chemical transformations. Traditionally, catalysis has been subdivided into two areas: homogeneous and heterogeneous catalysis. Homogeneous catalysis refers to single-sited catalysts that exist in the same phase as the reaction media. These catalysts tend to be highly active and selective but often difficult to recover and reuse. In contrast, heterogeneous catalysts are typically multi-sited catalysts that exist in a different phase from the reaction media. These catalysts tend to be less active and selective than their homogeneous counterparts. However, the vast majority of industrial scale catalysts are heterogeneous because they can be easily separated, making them easily implemented in continuous processes, allowing for efficient, large scale operations. Due to the limitations of traditional homogeneous and heterogeneous catalysts, researchers have increasingly investigated hybrid catalysts that incorporate aspects of homogeneous and heterogeneous catalysis. This is accomplished via immobilization of homogeneous catalyst analogues onto solid-phase supports, thereby preserving the activity and selectivity of homogeneous catalysts while allowing for facile recovery and reuse from the insoluble, heterogeneous support. A variety of systems is presented here including organic and organometallic catalysts immobilized on organic and inorganic supports. Five cases are included. The first discusses utilization of supported acid and base catalysts for use in one-pot cascade reactions. The second example illustrates use of silica-coated magnetic nanoparticle supported acid catalysts for organic transformations. The third case presents novel polymer brush supported Cobalt-salen catalysts for the enantioselective, hydrolytic kinetic resolution of epoxides. A fourth case presents novel, magnetic polymer brush supported organic and organometallic catalysts for organic transformations. The fifth example illustrates polymer and silica supported ruthenium-salen catalysts for the asymmetric cyclopropanation of olefins. The overall goal of this thesis work is to develop novel supports and immobilization techniques to advance the field of hybrid organic/inorganic catalysts for the production of fine chemical and pharmaceutical intermediates.

Com o desenvolvimento da nanociência e da nanotecnologia, as nanopartículas magnéticas vêm sendo cada vez mais gerado interesse devido as inúmeras possíveis aplicações na área de catálise, diagnóstico, pigmentos, sensores, etc. Atualmente, as nanopartículas com potencialidade de aplicação em biomedicina que pode se destacar os as ferritas magnéticas os quais apresentam comportamento superparamagnético a temperatura ambiente. Além dos ligantes funcionais, as nanopartículas magnéticas são geralmente recobertas com polímeros orgânicos ou inorgânicos, destacando-se a sílica, nessa última classe. O sistemas as nanopartículas magnéticas recobertas com sílica formando um sistema casca-caroço, possibilita que o núcleo magnético se mantenha protegido por uma camada polimérica que pode conter grupos funcionais ativos, formando hidridos orgânicos-inorgânicos que devido a sua propriedade hidrofóbica ou hidrofílica dependendo da natureza do ligante de modificação de superfície. Este trabalho foi desenvolvido com intuito de obter nanopartículas magnéticas de ferrita MFe2O4, com (M= Fe, Co, Ni e Cu) com controle de tamanho, forma, composição química e estrutural, dos quais foram sintetizados pelo método de decomposição térmica utilizando diferente precursores metálicos para adequação das melhores condições de síntese. As ferritas magnéticas foram recobrimento com sílica, modificando da superfície da partícula e possibilitando caráter hidrofílico ao sistema casca-caroço, apresentando uma melhor estabilidade coloidal em dispersão aquosa devido a presença de grupos silanois na superfície, bem como uma recobrimento uniforma com apenas um núcleo magnético sem formação de aglomerados. A funcionalização com o grupo o trietoxivinilsilano, através de reações de condensação via catálise básica ou ácida, formou uma rede polimérica Si-O-Si, sendo que a presença do grupo vinil (-CH=CH2) livre na a superfície do sistema casca-caroço foi evidenciado através da técnica de FTIR. Portanto foi possível a obtenção de um sistema hibrido orgânico-inorgânico com a superfície contendo grupo que podem ser reativos, abrindo a possibilidade da utilização deste material para futuros testes de aplicações como sensor multifuncional. / In recent decades the development of nanoscience and nanotechnology, magnetic nanoparticles have been increasingly generated interest due to the numerous possible applications in the field of catalysis, diagnosis, pigments, sensors, etc. Currently, the nanoparticles with potential of application in biomedicine that can stand out the magnetic ferrites which have superparamagnetic behavior at room temperature. In addition to the functional binders, magnetic nanoparticles are generally coated with organic or inorganic polymers, especially silica in the latter class. The magnetic nanoparticle systems covered with silica forming a shell-core system allow the magnetic core to remain protected by a polymeric layer that may contain active functional groups, forming organic-inorganic hydrides that due to its hydrophobic or hydrophilic property depending on the nature of the surface modifying binder. This work was developed to obtain magnetic nanoparticles of MFe2O4 ferrite, with (M = Fe, Co, Ni and Cu) control of size, shape, chemical and structural composition, of which were synthesized by the thermal decomposition method using different precursors to suit the best conditions of synthesis. The magnetic ferrites were coated with silica, modifying the surface of the particle and allowing a hydrophilic character to the shell-core system, presenting a better colloidal stability in aqueous dispersion due to the presence of silane groups on the surface, as well as a uniform coating with only one magnetic core without formation of agglomerates. The functionalization with the triethoxyvinylsilane group, through condensation reactions via basic or acid catalysis, formed a Si-O-Si polymer network, and the presence of the free vinyl group (-CH=CH2) on the shell surface was observed by FTIR technique. Therefore, it was possible to obtain an organic-inorganic hybrid system with the surface containing the reactive group, opening the possibility of using this material for tests of future applications as multifunctional sensor.

Orientadores: Flávio Garcia, Kleber Roberto Pirota / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-24T22:02:36Z (GMT). No. of bitstreams: 1 Dias_CarlosSatoBaraldi_D.pdf: 19717682 bytes, checksum: 212154446eec9e3ee26eee15692adfec (MD5) Previous issue date: 2014 / Resumo: Durante este trabalho, estudamos a viabilidade de uma nova classe de partículas magnéticas otimizadas para a hipertermia magnética e que denominamos VIP (Vortex Iron oxide Particle). Estas partículas são compostas de óxidos de ferro (magnetita ou maghemita) e assumem a forma de nanoanéis ou nanotubos. Tal morfologia confere as partículas um comportamento magnético peculiar, fruto de seu estado magnético denominado vórtice. Graças a este estado magnético, estas partículas possuem uma resposta para hipertermia superior, se comparadas aos SPIONs (Superparamagnetic Iron Oxide Nanoparticles) tradicionalmente usados para este fim, atendendo os pré-requisitos para aplicações biomédicas (baixas toxicidade e remanência). Os experimentos realizados no trabalho se focaram em duas linhas principais. Na primeira, avaliamos o desempenho das VIPs para hipertermia magnética em um ambiente in vitro. Neste experimento, avaliamos tanto a citotoxicidade das partículas quanto os mecanismos que promovem a morte celular. Estes resultados mostraram que as VIPs não são citotóxicas. Além disso, observamos também que o tamanho e a forma das partículas permitem que estas sejam internalizadas, promovendo um processo de hipertermia magnética muito eficiente. De fato, o experimento de hipertermia in vitro mostrou que as VIPs são capazes de alcançar um alto grau de seletividade, matando principalmente as células que internalizam as VIPs minimizando o aquecimento do meio celular e reduzindo assim o dano às células vizinhas. Na segunda linha, trabalhamos no desenvolvimento de uma VIP recoberta com material antiferromagnético (AFM), cujo desempenho para hipertermia magnética seria superior ao da própria VIP testada nos experimentos in vitro. Desenvolvemos um extenso estudo teórico fundamental, baseado em simulações micromagnéticas, que permitiram prever muitos dos fenômenos que seriam observados experimentalmente. No entanto os experimentos para a síntese da VIP@AFM não foram completamente finalizados, impossibilitando maiores conclusões sobre o sistema simulado. Sendo assim, acreditamos que os resultados alcançados no projeto promoveram o desenvolvimento de partículas magnéticas otimizadas para hipertermia magnética. Tanto por mostrar sua viabilidade, quando testados in vitro, quanto por promover o conceito da VIP@AFM como um próximo passo para o aprimoramento desta classe de partículas / Abstract: In this work, we studied the feasibility of a new class of magnetic particles named as Vortex Iron oxide Particle or VIP and specifically designed for magnetic hyperthermia. Those iron oxide (magnetite or magnetite) particles have a ring shape morphology that grants them a very specific magnetic configuration know as vortex state. This magnetic configuration would grant a superior hyperthermia response when compared to the traditional Superparamagnetic Iron Oxide Particle (SPION) without compromising biomedical requirements as low cytotoxicity and lack of magnetic remanence. The experiments presented on this work explored two main paths. The first one evaluated the VIP performance in vitro. We were able to assess both the cytotoxicity of the particle as to observe the killing mechanism. The results showed that the VIPs are not cytotoxic and that the size and shape of the particle may promote the internalization of those particles, resulting on a very efficient magnetic hyperthermia. With the in vivo experiment, we notice a high degree of selectivity, thanks to the cell internalization, that preserved the surrounding cells. In the second research path, we further developed the concept of a VIP, by creating a core-shell structure where the VIP would be coated by an antiferromagnetic (AFM) material and improving the magnetic hyperthermia response. However, the experiments for the development of the VIP@AFM were not completed. Although we were able to complete a study based on micromagnetic simulations, the experiments intending to fabricate the VIP@AFM were not fully successful, preventing any further conclusion about this system. In any case, we believe that the results achieved on this project represent an important contribution to the development of magnetic hyperthermia specific particles / Doutorado / Física / Doutor em Ciências

We study the metastability of magnetic nanoparticles with size distributions. We simulate an array of magnetic nanoparticles with a spin S = 1 ferromagnetic Blume-Capel model on a square lattice. Studying decays of the metastable state in the Blume-Capel model at low temperatures requires an extremely long computational time in kinetic Monte Carlo simulations. Therefore, we use an advanced algorithm adapted from the Monte Carlo with absorbing Markov chain algorithm for the Ising model in order to study the Blume-Capel model with size distributions. We modeled the particle size distributions as distributions of magnetic anisotropy. We compute the low-temperature average lifetime of the magnetization relaxation using kinetic Monte Carlo simulations with the advanced algorithms. We also calculate the lifetime using the absorbing Markov chains method for analytical results. Our results show that the lifetime of the metastable state follows a modified-Arrhenius law where the energy barrier has a dependency on temperature and standard deviation of the distributions in addition to magnetic field and magnetic anisotropy. The magnetic anisotropy barrier is determined by the smallest particle within a given distribution. We also study magnetization relaxation in different single critical droplet regions using different dynamics: Glauber and phonon-assisted dynamics. We find that the lifetime follows the modified-Arrhenius law for both dynamics, and an explicit form of the lifetime differs in different regions for different dynamics. For the Glauber dynamics, the Arrhenius prefactor does not depend on the standard deviation of the distribution of the magnetic anisotropy. For the phonon-assisted dynamics, however, even the prefactor of the lifetime depends on the standard deviation and is significantly reduced for a wide distribution of magnetic anisotropy. Furthermore, the phonon-assisted dynamics forbids transitions between degenerate energy states and results in an increase of the energy barrier at the single critical droplet region boundary compared to that for the Glauber dynamics. We find that the spin system with a distribution of magnetic anisotropy finds lower-energy relaxation pathways to avoid degenerate state, and the energy barrier becomes the same for both dynamics. / Ph. D.

Hydrogels are popular materials for biological applications since they exhibit properties like that of natural soft tissue and have tunable properties. Biodegradable hydrogels provide an added advantage in that they degrade in an aqueous environment thereby avoiding the need for removal after the useful lifetime. In this work, we investigated poly(β-amino ester) (PBAE) biodegradable hydrogel systems. To begin, the factors affecting the macromer synthesis procedure were studied to optimize the reproducibility of the resulting hydrogels made and create new methods of tuning the properties. Hydrogel behavior was then tuned by altering the hydrophilic/hydrophobic balance of the chemicals used in the synthesis to develop systems with linear and two-phase degradation profiles. The goal of the research was to better understand methods of controlling hydrogel properties to develop systems for several biomedical applications. Several systems with a range of properties were synthesized, and their in vitro behavior was characterized (degradation, mechanical properties, cellular response, etc.). From these studies, materials were chosen to serve as porogen materials and an outer matrix material to create a composite scaffold for tissue engineering. In most cases, a porous three dimensional scaffold is ideal for cellular growth and infiltration. In this work, a composite with a slow degrading outer matrix PBAE with fast degrading PBAE microparticles was created. First, a procedure for developing porogen particles of controlled size from a fast-degrading hydrogel material was developed. Porogen particles were then entrapped in the outer hydrogel matrix during polymerization. The resulting composite systems were degraded and the viability of these systems as tissue engineering scaffolds was studied. In a second area of work, two polymer systems, one PBAE hydrogel and one sol-gel material were altered through the addition of iron oxide nanoparticles to create materials with remote controlled properties. Iron oxide nanoparticles have the ability to heat in an alternating magnetic field due to the relaxation processes. The incorporation of these nanoscale heating sources into thermosensitive polymer systems allowed remote actuation of the physical properties. These materials would be ideal for use in applications where the system can be changed externally such as in remote controlled drug delivery.

[pt] Estudos com nanopartículas magnéticas têm sido realizados no âmbito da medicina tanto para tratamento de tumores e câncer, quanto para fins de diagnósticos ou ainda para transporte de fármacos. Nanopartículas magnéticas podem ser administradas a alvos específicos e mantidas no local adequado por meio de um campo magnético aplicado. Com este propósito, as nanopartículas com um núcleo de material magnético são recobertas com material adequado para sua funcionalização. Neste trabalho sintetizamos nanopartículas de óxido de ferro e funcionalizamos sua superfície com uma bicamada que permitiu criar um compartimento adequado à solubilização de fármacos hidrofóbicos. Nesse compartimento foi solubilizada uma ftalocianina que se mostrou promissora como fotossensibilizante em terapia fotodinâmica. Fotossensibilizantes são moléculas que, ao interagir com a luz, formam espécies altamente reativas, como o oxigênio singlete, que destroem células e tecidos adjacentes. Este processo é utilizado em Terapia Fotodinâmica (PDT). A geração de oxigênio singlete pela ftalocianina no compartimento hidrofóbico foi avaliada usando como sonda o 1,3-difenil isobenzofurano (DPBF), em formulações com os surfactantes não iônicos, Tween 80 e Pluronic 127. Com o objetivo de controlar a liberação de fármacos, construímos um circuito eletrônico para produzir um campo magnético AC que atua sobre as partículas magnéticas e produz um aumento local de temperatura. O aumento de temperatura modifica a difusão das moléculas localizadas na camada que recobre as nanopartículas, o que permite variar a taxa de liberação. Foi estudada a variação de temperatura produzida na presença do campo magnético AC. Foi estudado também o efeito da temperatura na produção de oxigênio singlete. / [en] Magnetic nanoparticles have been studied aiming at medical applications, such as treatment of tumors and cancer, for diagnostic purposes and drug delivery. Magnetic nanoparticles can be administered to specific targets and maintained in the proper location by means of an applied magnetic field. For this purpose, nanoparticles with a core of magnetic material are coated with suitable material for functionalization. In this work, we synthesized nanoparticles of iron oxide and functionalized their surface with a bilayer that served as an appropriate compartment for hydrophobic drugs. A promising phthalocyanine derived photosensitizer was solubilized in this compartment. Photosensitizers are molecules that interact with light to form highly reactive species such as singlet oxygen, which destroy cells and surrounding tissues. This process is used in photodynamic therapy (PDT). The generation of singlet oxygen by the phthalocyanine in the hydrophobic compartment was evaluated using the probe 1,3- diphenyl isobenzofuran (DPBF) in formulations with the nonionic surfactants Tween 80 and Pluronic F-127. Aiming to control the release of drugs, we build an electronic circuit to produce an AC magnetic field which acts on the magnetic particles to produce a local temperature increase. This increase in temperature modifies the diffusion of molecules at the surface layer of the nanoparticles, and allows to control the rate of release. Temperature variation produced in the presence of the AC magnetic field was studied. The effect of temperature on the singlet oxygen production was also studied.

Made available in DSpace on 2014-12-17T14:16:32Z (GMT). No. of bitstreams: 1 JulianaFC_DISSERT.pdf: 2465662 bytes, checksum: 2528260c5aedc6b5fb63748e3692e16a (MD5) Previous issue date: 2013-02-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The drug targeting has been the subject of extensive studies in order to develop site-specific treatments that minimize side effects and become more effective anticancer therapy. Despite considerable interest in this class, drugs like antibiotics also have limitations, and have been neglected. Using new pharmaceutical technologies, the use of magnetic vectors appear as promising candidate for drug delivery systems in several studies. Small magnetic particles bound to the drug of interest can be modulated according to the orientation of a magnet outside the body, locating and holding in a specific site. In this work, we propose the use of High Energy Milling (HEM) for synthesis of a magnetic vector with characteristics suitable for biomedical applications by intravenous administration, and for the formation of an oxacillin-carrier complex to obtain a system for treating infections caused by Staphylococcus aureus. The results of the variation of milling time showed that the size and structural properties of the formed material change with increasing milling time, and in 60 hours we found the sample closest to the ideal conditions of the material. The vector-drug system was studied in terms of structural stability and antimicrobial activity after the milling process, which revealed the integrity of the oxacillin molecule and its bactericidal action on cultures of Staphylococcus aureus ATCC / A vetoriza??o de f?rmaco tem sido alvo de exaustivos trabalhos no intuito de desenvolver tratamentos s?tio-espec?ficos que minimizem efeitos adversos e torne mais efetiva a terapia antineopl?sica. Apesar do grande interesse nessa classe, f?rmacos como os antibi?ticos tamb?m apresentam limita??es, e t?m sido negligenciados. Utilizando novas tecnologias farmac?uticas, o emprego de vetores magn?ticos aparece como candidato promissor para sistemas de entrega de f?rmaco em in?meros estudos. As pequenas part?culas magn?ticas ligadas ao f?rmaco de interesse podem ser moduladas de acordo com a orienta??o de um ?m? externo ao corpo, localizado e retendo o ativo no local de interesse. Nesse trabalho n?s propomos a utiliza??o de Moagem de Alta Energia (MAE) para s?ntese do vetor magn?tico com caracter?sticas apropriadas para aplica??es biom?dicas por via de administra??o intravenosa, e para complexa??o do carreador ? Oxacilina para obten??o de um sistema para tratamento de infec??es por Staphylococcus aures. Os resultados da varia??o do tempo de moagem demonstraram que as propriedades estruturais e de tamanho do material formado se alteram com o aumento do tempo de moagem, e dentre os per?odos estudados, 60 horas foi escolhido como o mais pr?ximo das propriedades ideais do material. A complexa??o vetor-f?rmaco foi estudada em termos de estabilidade estrutural e de atividade antimicrobiana ap?s o processo de moagem, que revelaram a integridade da mol?cula de Oxacilina e de sua a??o bactericida sobre culturas de Staphylococcus aures ATCC

Mutation and loss of p53 function are common features among human breast cancers. We use BALB/c-Trp53+/- mice as a model to examine the sequence of events leading to mammary tumors. Mammary epithelium proliferation rates were similar in both BALB/c-Trp53+/- mice and wild type controls. Among the 28 mammary tumors collected from BALB/c-Trp53+/- mice, loss of heterozygosity for Trp53 was detected in more than 90% of invasive mammary tumors. Transplantation of Trp53+/- ductal hyperplasias indicated an association between loss of the wild type allele of Trp53 and progression to invasive carcinomas. Expression of biomarkers such as ERα, PR, Her2/Neu and activated Notch1 varied among the tumors suggesting that multiple oncogenic events collaborate with loss of p53 function. The majority of the tumors expressed both luminal and basal cytokeratins (59%). Gene expression analysis showed ligands and receptors of stem cell related pathways, such as Notch and Wnt, were increased in the tumors. These results indicate that mammary tumors in BALB/c Trp53+/- mice might initiate from bipotent mammary progenitor cells. USING MAGNETIC NANOPARTICLES FOR CANCER THERMOTHERAPY Alternating magnetic field (AMF) heating of magnetic nanomaterials provides a promising method for executing therapeutic thermal treatment for cancer patients. In order to explore the potential of magnetic nanoparticles (MNPs) for hyperthermia treatment, we synthesized iron oxide MNPs with various passivation by citric acid, folate, trimethylamine carboxylic acid, or albumin. The albumin passivated MNP (MNP-A) surpassed other MNPs, showing efficient heating with very low inherent cytotoxicity. Confocal microscopy located MNP-A (FITC tagged) accumulation in both cell nucleus and cytosol after 24hr incubation with HeLa cells. The quantity of cell bound MNP-A (including internalized and cell membrane bound MNP-A) was positively associated with MNP-A concentration and incubation time with cells. The MNP-A bound to cells was sufficient to increase the temperature in the cell pellet Δ7°C after 8min exposure to AMF. No significant temperature increase or cell death was detected in control groups. Our data demonstrate that MNP-A provides a selective tool for AMF-induced thermal treatment, as well as useful dosing information for future preclinical animal studies.

The idea of utilizing nanomaterials in bio-related applications has been extensively practiced during the recent decades. Magnetic nanoparticles (MPs), especially superparamagnetic iron oxide nanoparticles have been demonstrated as promising candidates for biomedicine. A protective coating process with biocompatible materials is commonly performed on MPs to further enhance their colloidal and chemical stability in the physiological environment. Mesoporous hollow silica is another class of important nanomaterials that are extensively studied in drug delivery area for their ability to carry significant amount of guest molecules and release in a controlled manner. In this study, different synthetic approaches that are able to produce hybrid nanomaterials, constituting both mesoporous hollow silica and magnetite nanoparticles, are described. In a two-step approach, pre-synthesized magnetite nanoparticles are either covalently conjugated to the surface of polystyrene beads and coated with silica or embedded/enclosed in the porous shell during a nanosized CaCO3 templated condensation of silica precursors, followed by acid dissolution to generate the hollow structure. It was demonstrated that the hollow interior is able to load large amount of hydrophobic drugs such as ibuprofen while the mesoporous shell is capable of prolonged drug. In order to simplify the fabrication procedure, a novel in-situ method is developed to coat silica surface with magnetite nanoparticles. By refluxing the iron precursor with mesoporous hollow silica nanospheres in polyamine/polyalcohol mixed media, one is able to directly form a high density layer of magnetite nanoparticles on silica surface during the synthesis, leaving reactive amine groups for further surface functionalization such as fluorescence conjugation. This approach provides a convenient synthesis for silica nanostructures with promising potential for drug delivery and multimodal imaging. In addition to nanoparticles, nanowires also benefit the research and development of instruments in clinical diagnosis. Semiconductive nanowires have demonstrated their advantage in the fabrication of lab-on-a-chip devices to detect many charge carrying molecules such as antibody and DNA. In our study, In2O3 and silicon nanowire based field effect transistors were fabricated through bottom-up and top-down approaches, respectively, for ultrasensitive bio- detection of toxins such as ricin. The specific binding and non-specific interaction of nanowires with antibodies were also investigated.

Les catalyseurs supportés sur des dendrimères et nanoparticules magnétiques acquièrent actuellement une importance accrue dans le contexte de la chimie verte et du développement durable car ils sont séparés facilement des produits de réaction par filtration ou à l’aide d’un aimant et recyclables. Dans cet esprit, la thèse a été dédiée à la synthèse, à la caractérisation et aux applications catalytiques de catalyseurs moléculaires, nano-et dendritiques immobilisés impliquant le ruthénium, le cuivre et le palladium. Les catalyseurs magnétiquement recyclables de ruthenium (II), de cuivre (I) et des nanoparticules de palladium ont produit d’excellentes performances en terme d’activité, de stabilité et de recyclabilité pour les réactions de cycloaddition entre les alcynes et les azotures et les réactions de couplage croisé carbone-carbone. Enfin, la synthèse de complexes mono-et polymétalliques du palladium contenant les ligands 2-pyridyl-1,2,3-triazole a également été réalisée et leurs proprietiés catalytiques ont été étudiées. / Catalysts based on dendrimers and magnetic nanoparticles are becoming increasing utilized in the context of green and sustainable chemistry, because they are easily separated by precipitation or by using asimple magnet respectively, and they are recyclable. In this spirit, the thesis has been devoted to the synthesis, characterization and catalytic applications of iron oxide magnetic nanoparticles-immobilized molecular, nano-and dendritic catalysts involving Ru, Cu and Pd. Magnetically recyclable ruthenium(II) and Cu(I) complexes and Pd nanoparticles have provided excellent catalytic performances in terms of activity, stability and recyclability, using alkyne-azide cycloaddition and carbon-carbon cross coupling reactions. The synthesis of mono-and polymetallic palladium complexes containing the 2-pyridyl-1,2,3-triazole ligand or nonabranch-derived ligands has also been carried out, and their catalytic properties in coupling reactions has been studied