Le but principal de ce travail a été de mettre en évidence le potentiel synthétique de nouvelles bases mixtes fer-lithium dans des réactions de déprotométallation en série aromatique. Dans un premier chapitre, les travaux de la littérature sur les composés fer-métal alcalin et notamment les bases ont d’abord été exposés. Notre étude a permis d’optimiser  une  nouvelle base fer-lithium et a montré la capacité de celle-ci à réaliser des réactions de déprotonation relativement chimiosélectives et efficaces. Les paramètres de la réaction de déprotométallation ont été optimisés en utilisant l’iode comme électrophile. Cette méthode a été étendue à divers hétérocycles et le piégeage subséquent à différents électrophiles. Dans un second chapitre, le comportement de la base fer-lithium développée a été comparé à celui d’autres bases bimétalliques utilisées au laboratoire. La fonctionnalisation des triazoles par ces bases a montré que la base zinc-lithium était la base la plus appropriée pour ce type de substrats. La fonctionnalisation à l’aide de cette base a donc été étendue en série indazole et benzotriazole. Les résultats ont été rationalisés en utilisant les acidités des hydrogènes des substrats (pKₐ). Dans un dernier chapitre, les méthodes développées ont été valorisées par la synthèse de 2,4-diaryl-1,2,3-triazoles analogues du resvératrol. Les propriétés cytotoxiques de ces molécules seront évaluées. Cette application reste à approfondir. / The main purpose of this work was to highlight the synthetic potential of new mixed iron-lithium bases in aromatic deprotometallation reactions. In the first chapter, literature works about iron-alkali metal compounds and notably bases were firstly presented. Our study led to the optimization of a new iron-lithium base and showed its ability to achieve rather chemoselective and efficient deprotonation reactions. The reaction parameters of deprotometallation were optimized by using iodine as the electrophile. This method was extended to various heterocycles and the subsequent trapping to different electrophiles. In a second chapter, the behaviour of the iron-lithium base developed was compared with that of other bimetallic bases used in th laboratory. The functionalization of triazoles using these bases showed that the zinc-lithium was the most suitable base for this kind of substrate. Thus, the functionalization using this base was extended to indazole and benzotriazole series. The results were rationalized by using the hydrogen acidities of the substrates (pKₐ). In the last chapter, the methods developed were made more attractive by the synthesis of 2,4-diaryl-1,2,3-triazoles analogues of resveratrol. The cytotoxic properties of these molecules will be evaluated. This application remains to be explored.

Esta tese descreve, em dois diferentes capítulos, a síntese assimétrica da Malevamida D e a aplicação de compostos organotelúrio em reações de Suzuki-Miyaura. O primeiro capítulo refere-se ao estudo da síntese assimétrica da Malevamida D, um depsipeptídeo natural pertencente à família das dolastatinas, compostos estes com grande atividade citotóxica. As unidades DAP e MMMAH foram alcançadas em ótimos redimentos e estereosseletividades, utilizando-se reações de adição de crotil ou aliltrifluoroborato de potássio à aldeídos derivados da L-prolina e L-isoleucina, respectivamente. A elongação da cadeia da malevamida D se fez a partir de reações de esterificação e amidação; infelizmente não foi possível completar a síntese devido a problemas na última reação de acoplamento peptídico. O segundo capítulo descreve as reações entre teluretos aromáticos ou vinílicos e sais de organotrifluoroborato de potássio, mediadas por um catalisador de paládio. A partir destas reações de acoplamento cruzado tipo Suzuki-Miyaura foi possível obter-se 1,3-eninos, sistemas biarílicos, (E)- ou (Z)-estilbenos e 1,3-dienos. Todas as reações mostraram serem tolerantes a uma grande variedade de grupos funcionais e altamente estereoconservativas, nos casos envolvendo substratos vinílicos. / This thesis describes, in two different chapters, the asymmetric synthesis of malevamide D and the application of organotellurium compounds in Suzuki-Miyaura reaction. The first chapter refers to the asymmetric synthesis of malevamide D, a natural depsipeptide which belongs to the dolastatins family, and these compounds have a great interest due to theirs citotoxic activities. The DAP and MMMAH units were reached in excellent yields and stereoselectivities from 1,2-addition reaction of potassium crotyl or allyltrifluoroborate to aldehydes derivate from L-proline and L-isoleucine, respectively. The malevamide D elongation was made from reaction of esterification and amidation, unfortunately it was not possible finish the synthesis due to some problems in the last step of the total synthesis. The second chapter describes the reaction between aryl or vinyl tellurides and potassium organotrifluoroborate salts, mediated by a palladium catalyst. From this cross-coupling reaction type Suzuki-Miyaura was possible obtain 1,3-dienes, biarylic systems, (E)- or (Z)-stylbenes and 1,3-dienes. Al reactions showed to be tolerant to a wide range of functional groups and highly stereoconservative, in the cases involving vinylic substrates.

A malária é uma das principais causas de morte em muitos países de clima tropical, matando mais de 438 mil pessoas anualmente em todo o mundo. Desta forma, o objetivo do presente trabalho foi sintetizar compostos fluorescentes 2,5- diarilfuranos através da reação de acoplamento cruzado tipo Suzuki-Miyaura e acoplar ao fármaco Primaquina para utilizá-los laboratorialmente como biomarcadores específicos, carreadores de substâncias, parasiticidas, além do desenvolvimento de novo método diagnóstico. Através deste tipo de reação, foram sintetizados 3 compostos fluorescentes: a sonda 3-AFA, 3-AFA ala e a 4-AFAPQ. Inicialmente foram utilizadas células primárias, células da linhagem RAW 264.7 e células eritrocíticas, estas provenientes de camundongos Balb/c inoculados pela via intraperitoneal com 106 EI/mL de P. berghei ANKA GFP. Os compostos fluorescentes sintetizados 3-AFA e 3-AFA ala foram incubados com as células acima citadas e verificou-se a capacidade de as sondas penetrarem e marcarem células sadias e/ou infectadas. A aquisição dos resultados foi realizada por meio de citometria de fluxo e microscopia confocal. A partir daí, utilizou-se também sangue humano proveniente de doação que foi infectado com P. falciparum 3D7. A análise dos resultados realizada com microscopia de fluorescência e testes de EC50 com estes eritrócitos, além de células HepG2. As sondas 3-AFA e 4-AFAPQ foram incubadas com estas células para avaliar a ação parasiticida, bem como a citotoxicidade destes compostos. Nossos resultados mostraram que as sondas 3-AFA e 3-AFA ala não foram capazes de penetrar os macrófagos. Entretanto, foram capazes de atravessar a membrana dos eritrócitos infectados marcando o parasita. Quando os compostos 3- AFA e a 4-AFAPQ foram inseridos em eritrócitos humanos infectados pelo P. falciparum 3D7, foi possível observar que ambos marcaram o parasita em suas 3 fases. Mas resultados de EC50 mostraram que os compostos não possuem efeito parasiticida. E podemos concluir que estes compostos não são citotóxicos ás células possuindo então, um potencial em serem estudados mais a fundo, com algumas modificações em suas estruturas para melhorar assim, sua eficiência quanto a seletividade. Diante destes compostos potencialmente fluorescentes, foi possível também desenvolver um novo método de diagnóstico rápido simples e barato que pode possibilitar o alcance em locais aonde os métodos convencionais de microscopia não chegam. / Malaria is a major cause of death in many tropical countries, killing over 438 thousand people annually worldwide. Thus, the objective of this study was to synthesize fluorescent compounds 2,5-diarylfuranes through cross-coupling reaction like Suzuki-Miyaura and engage the drug Primaquine to use them as laboratory specific biomarkers, carriers of substances, parasiticide, and the development new diagnostic method. Through this type of reaction, three fluorescent compounds were synthesized: probe 3-AFA, 3-AFA ala and 4-AFAPQ. Initially were used primary cells, strain RAW 264.7 cells line and erythrocytic cells, those derived from Balb/c mice inoculated intraperitoneally with 106 IE/mL of P. berghei ANKA GFP. The synthesized fluorescent compounds 3-AFA and 3-AFA ala were incubated with the above said cells and found the ability of penetrating probes and mark healthy cells and/or infected. The acquisition of the results was performed by flow cytometry and confocal microscopy. From there, it was also used human blood from that donation was infected with P. falciparum 3D7. The analysis performed with fluorescence microscopy and EC50 these tests with erythrocytes, and HepG2 cells. The probes 3-AFA and 4-AFAPQ were incubated with these cells to evaluate the parasiticidal activity and cytotoxicity of these compounds. Our results showed that the probes 3-AFA and 3-AFA ala were not able to penetrate macrophages. However, they were able to pass the membrane of the parasite infected erythrocytes marking. When the fluorescents probes 3-AFA and 4- AFAPQ (coupled Primaquine) were inserted into human erythrocytes infected with P. falciparum 3D7, it was observed that both marked the parasite in her 3 phases. But EC50 results showed that the compounds do not have parasiticidal effect. And we can conclude that these compounds are not cytotoxic to the cells having then a potential be studied further, with some modifications in their structures to improve thus efficiency and selectivity. Given these potentially fluorescent compounds, it was possible to develop a new method of simple and inexpensive rapid diagnosis that can enable the range in places where conventional methods of microscopy not arrive.

As células solares poliméricas (PSCs) e diodos emissores de luz poliméricos (PLEDs) destacam-se dos seus análogos inorgânicos pela possibilidade de reduzir custo de fabricação, obtenção de dispositivos mais leves e flexíveis, maior liberdade no design e menor tempo de produção de dispositivos, devido à sua maior facilidade de processamento. Neste trabalho foram investigadas as mudanças nas propriedades fotofísicas, eletroquímicas e elétricas do poli[2,7-(9,9-dioctilfluoreno)-alt-4,7-bis(2,5-tiofeno)-2,1,3-benzotiadiazol] (PDBT) e seus derivados contendo grupos substituintes hexila no anel tiofeno. Este polímero conjugado é conhecido por seu potencial para aplicações em PSCs. Para tanto, três copolímeros, contendo diferentes concentrações de mero tiofeno substituído, foram sintetizados via reação de acoplamento de Suzuki. Usando técnicas adequadas, foram verificadas correlações entre o comportamento fotofísico, térmico e elétrico dos copolímeros e o teor de tiofeno substituído. Os materiais poliméricos sintetizados foram aplicados como camada ativa em PLEDs e PSCs. Em relação aos PLEDs, foi verificada baixa luminância e emissão de luz na faixa da cor laranja e cor verde. Além disso, diferentes efeitos, relacionados com a concentração de tiofeno substituído e as propriedades fotovoltaicas, foram identificados nas PSCs montadas. / Polymer Solar cells (PSCs) and polymer light-emitting diodes (PLEDs) draw attention from their inorganic analogues for the possibility of manufacturing cost reduction, more light and flexible devices, as well as the greater design freedom and shorter production time devices due to its easier processing. In this work, we investigated the changes in the photophysical, electrochemical and electrical properties from poly[2,7-(9,9-dioctylfluorene)-alt-4,7-bis(2,5-thiophene)-2,1,3-benzothiadiazole] (PDBT) that was caused by hexyl substituents introduction on the copolymer thiophene rings. This conjugated polymer system is known for its PSCs applications potential. Therefore, three copolymers, with different concentrations of substituted thiophene mere, were synthesized by Suzuki polycondensation. Using appropriate techniques, direct relationships were verified between the photophysical, thermal and electrical behavior from copolymers and substituted thiophene content. The synthesized polymeric materials were applied as active layer in PLEDs and PSCs. Regarding PLEDs, it was verified a low luminance and light emission in the range of orange and green colors. Furthermore, different effects, related to the substituted thiophene concentration and photovoltaic properties, were identified from mounted PSCs.

Em que medida é possível pensar a elaboração de um discurso cênico desvinculada dos procedimentos e meios técnicos aplicados a ela? Ou, por outro lado, até que ponto a escolha de procedimentos e técnicas específicas determinam um fazer poético? No teatro ocidental, o tema do entrecruzamento de procedimentos com a construção do discurso poético passa a ser problematizado a partir do final do século XIX com o advento da encenação, possibilitando a construção de um novo diálogo entre encenação e pedagogia e o desenvolvimento de várias reflexões sobre o trabalho do ator. Tadashi Suzuki, encenador japonês contemporâneo, se insere nesse contexto ao sistematizar um treinamento para atores que lhes permita viabilizar seus objetivos estéticos e a criação de seus espetáculos. Além de proporcionar a aproximação com o trabalho deste encenador que, embora mundialmente conhecido, ainda é pouco divulgado no Brasil, o projeto se insere nas reflexões teórico-práticas surgidas a partir do trabalho de Suzuki e que são pertinentes ao teatro contemporâneo. Reflexões que dizem respeito às articulações entre material técnico e material poético na escritura cênica, à pedagogia teatral e, especialmente, às pesquisas da linguagem da encenação que tomam o ator como fonte geradora de códigos performáticos. / To what extent is it possible to think of the elaboration of a scenic speech separately from the procedures and technical means applied to it? Or, on the other hand, to what point does the choice of procedures and specific techniques determine a poetic work? In the Western theater, the theme of crossing technical procedures with the construction of a poetic speech has become a problem in the theaters as from the 19th century with the arrival of staging, what made the construction of a new dialogue between staging and pedagogy and the development of various reflections about the actors work possible. Tadashi Suzuki, a contemporary Japanese director, becomes relevant in this context when he systematizes a training for actors, one that permits the practicability of their esthetic objectives and a creation of their spectacles. Apart from allowing an approche to this directors work, which despite being known worldwide is still not so publicized in Brazil, the project collaborates with theoreticalpractical reflections that arose from Suzukis work and that are pertinent to contemporary theater. Reflections that refer to the articulations between technical material and poetic material in the dramaturgy of the scene, to theatrical pedagogy and to the researches of the staging language that take the actor as a source of performance codes.

As células solares poliméricas (PSCs) e diodos emissores de luz poliméricos (PLEDs) destacam-se dos seus análogos inorgânicos pela possibilidade de reduzir custo de fabricação, obtenção de dispositivos mais leves e flexíveis, maior liberdade no design e menor tempo de produção de dispositivos, devido à sua maior facilidade de processamento. Neste trabalho foram investigadas as mudanças nas propriedades fotofísicas, eletroquímicas e elétricas do poli[2,7-(9,9-dioctilfluoreno)-alt-4,7-bis(2,5-tiofeno)-2,1,3-benzotiadiazol] (PDBT) e seus derivados contendo grupos substituintes hexila no anel tiofeno. Este polímero conjugado é conhecido por seu potencial para aplicações em PSCs. Para tanto, três copolímeros, contendo diferentes concentrações de mero tiofeno substituído, foram sintetizados via reação de acoplamento de Suzuki. Usando técnicas adequadas, foram verificadas correlações entre o comportamento fotofísico, térmico e elétrico dos copolímeros e o teor de tiofeno substituído. Os materiais poliméricos sintetizados foram aplicados como camada ativa em PLEDs e PSCs. Em relação aos PLEDs, foi verificada baixa luminância e emissão de luz na faixa da cor laranja e cor verde. Além disso, diferentes efeitos, relacionados com a concentração de tiofeno substituído e as propriedades fotovoltaicas, foram identificados nas PSCs montadas. / Polymer Solar cells (PSCs) and polymer light-emitting diodes (PLEDs) draw attention from their inorganic analogues for the possibility of manufacturing cost reduction, more light and flexible devices, as well as the greater design freedom and shorter production time devices due to its easier processing. In this work, we investigated the changes in the photophysical, electrochemical and electrical properties from poly[2,7-(9,9-dioctylfluorene)-alt-4,7-bis(2,5-thiophene)-2,1,3-benzothiadiazole] (PDBT) that was caused by hexyl substituents introduction on the copolymer thiophene rings. This conjugated polymer system is known for its PSCs applications potential. Therefore, three copolymers, with different concentrations of substituted thiophene mere, were synthesized by Suzuki polycondensation. Using appropriate techniques, direct relationships were verified between the photophysical, thermal and electrical behavior from copolymers and substituted thiophene content. The synthesized polymeric materials were applied as active layer in PLEDs and PSCs. Regarding PLEDs, it was verified a low luminance and light emission in the range of orange and green colors. Furthermore, different effects, related to the substituted thiophene concentration and photovoltaic properties, were identified from mounted PSCs.

Em que medida é possível pensar a elaboração de um discurso cênico desvinculada dos procedimentos e meios técnicos aplicados a ela? Ou, por outro lado, até que ponto a escolha de procedimentos e técnicas específicas determinam um fazer poético? No teatro ocidental, o tema do entrecruzamento de procedimentos com a construção do discurso poético passa a ser problematizado a partir do final do século XIX com o advento da encenação, possibilitando a construção de um novo diálogo entre encenação e pedagogia e o desenvolvimento de várias reflexões sobre o trabalho do ator. Tadashi Suzuki, encenador japonês contemporâneo, se insere nesse contexto ao sistematizar um treinamento para atores que lhes permita viabilizar seus objetivos estéticos e a criação de seus espetáculos. Além de proporcionar a aproximação com o trabalho deste encenador que, embora mundialmente conhecido, ainda é pouco divulgado no Brasil, o projeto se insere nas reflexões teórico-práticas surgidas a partir do trabalho de Suzuki e que são pertinentes ao teatro contemporâneo. Reflexões que dizem respeito às articulações entre material técnico e material poético na escritura cênica, à pedagogia teatral e, especialmente, às pesquisas da linguagem da encenação que tomam o ator como fonte geradora de códigos performáticos. / To what extent is it possible to think of the elaboration of a scenic speech separately from the procedures and technical means applied to it? Or, on the other hand, to what point does the choice of procedures and specific techniques determine a poetic work? In the Western theater, the theme of crossing technical procedures with the construction of a poetic speech has become a problem in the theaters as from the 19th century with the arrival of staging, what made the construction of a new dialogue between staging and pedagogy and the development of various reflections about the actors work possible. Tadashi Suzuki, a contemporary Japanese director, becomes relevant in this context when he systematizes a training for actors, one that permits the practicability of their esthetic objectives and a creation of their spectacles. Apart from allowing an approche to this directors work, which despite being known worldwide is still not so publicized in Brazil, the project collaborates with theoreticalpractical reflections that arose from Suzukis work and that are pertinent to contemporary theater. Reflections that refer to the articulations between technical material and poetic material in the dramaturgy of the scene, to theatrical pedagogy and to the researches of the staging language that take the actor as a source of performance codes.

In the field of electronic organic materials, conjugated polymers (CPs) have attracted much attention in recent years. It has been well-established that performances of thin-film devices based on π-conjugated polymers, such as light-emitting diodes, field-effect transistors and photovoltaic cells, are strongly dependent on the organisation of the polymer molecules and their interactions with other constituents in multicomponent devices. The use of CPs in integrated circuits, solar cells, light-emitting diodes or sensors often requires their covalent fixation and patterning on various surfaces. CPs can be grafted to functionalized surfaces by (electro)chemical cross-linking; however, it is difficult to control a structural order within the cross-linked films. The attachment of CP chains to substrates by their end-points to form polymer brushes would be an interesting alternative, and could possibly be crucial for many devices requiring charge injection and charge transport processes. The main aim of this work, which was the synthesis of covalently grafted conjugated polymer brushes on solid substrates using a "grafting from" approach, was successfully performed. During the course of this work, the process of surface-initiated polycondensation was investigated. The newly developed method to selectively graft conjugated polymers from different substrates such as Si-wafers, quartz slides or modificated nanoparticles allowed us to produce different architectures which were earlier possible to prepare only non-conductive polymers. Exposure of the substrate with an activated surface layer into the monomer solution produced polymer brushes in a very economical way. Since only monomer was consumed for grafting from the surface. The grafting process was extensively investigated by different methods, and the thickness of the obtained poly(fluorene) films was elucidated by Null-ellipsometry and confirmed by the AFM scratch-test. Preliminary characteristics of the device, based on PS(Br)-core poly(octylfluorene)-shell nanoparticles, showed satisfactory results (such as turn-on voltage and electroluminescence in a blue region). They could be improved by replacement of the insulating PS(Br)-core of nanoparticles with other substances (semiconductive, etc.). There is still plenty of room for further development and improvement of the synthesis of poly(fluorene)-based polymer brushes. The polymer structures developed in this work can be utilized as an active layer in lab-on-chip devices. Alkyl groups in the 9th position of the poly(fluorene) monomer unit can be replaced by tailored receptors to detect specific species including small molecules, metal ions and biomolecules due to enhanced sensitivity through sensory signal amplification. Post-polymerization modifications may lead to highly water-swellable conjugated polyelectrolyte brushes. Also, polymerization of initially optically active fluorene-monomers may be the crucial step to the generation of a light source devices with a large degree of circularly polarized electroluminescence. This is of great interest for utilization as backlight for liquid crystalline displays. We believe that the utilization of covalently surface-immobilized conjugated polymers may have a great impact on the development of present-day technological processes.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The catalytic activity of hierarchical hybrid structures, formed by metal nanoparticles, M-NPs (AuNPs and PdNPs), synthesized and stabilized by block copolymers, is reported in this present work. The catalytic activity was investigated by the study of nanoparticle size and chemical nature of the block copolymer overlaying the M-NP. To evaluate the chemical structure effect of the polymer on catalytic properties of the hybrid systems, a series of eight distinct polymers was used: poly(ethylene oxide)113-b-poly(glycerol monomethacrylate)30-b-poly [2-(diisopropylamino)ethyl methacrylate]50 (PEO113-b-PG2MA30-b-PDPA50), poly(ethylene oxide)113-b-poly[2-(diethylamino)ethyl methacrylate]50 (PEO113-b-PDEA50) , poly(2- methacryloyloxyethyl phosphorylcholine)30-b- poly(2-(diisopropylamino) ethyl methacrylate)60 (PMPC30-b-PDPA60), poly(ethylene oxide)100-b-poly(propylene oxide)65-b-poly(ethylene oxide)100 (PEO100-b-PPO65-b-PEO100 or F127), α-carboxylic ω-thiol poly(N-isopropyl acrylamide)137 (HS-PNIPAM137-COOH), poly(4-vinylpyridine)137-b-(ethylene oxide)45 (PEO45-b-P4VP137), poly(N-vinyl caprolactam)94 (PNVCL94) and poly(N-vinyl caprolactam)53 (PNVCL53). The size of M-NPs was determined by dynamic light scattering (DLS) and their morphology was confirmed by transmission electron microscopy (TEM). Subsequently, was tested the catalyst efficiency, by the reduction of p-nitrophenol to p-aminophenol, the catalyst could be regenerated about 6 times, proving that system (AuNPs and PdNPs) as capacity for regeneration and can be an effective catalyst. The PdNPs were tested like catalyst in reactions of Suzuki coupling. / A atividade catalítica de estruturas hierárquicas híbridas formadas por nanopartículas metálicas, M-NPs (AuNPs e PdNPs), sintetizadas e estabilizadas por copolímeros em bloco é relatada neste trabalho. A atividade catalítica foi investigada em função da natureza química do copolímero em bloco que as revestem. Uma série de 08 (oito) polímeros estruturalmente relacionados foi utilizada: poli(óxido de etileno)113-b-poli(metacrilato de 2,3-diidroxipropila)30-b-poli(metacrilato de 2-(diisopropilamino)etila)50 (PEO113-b-PG2MA30-b-PDPA50), Poli(óxido de etileno)113-poli [ metacrilato de 2-(dietilamino)etil]50 (PEO113-b-PDEA50), poli(2-metacriloiloxietil fosforilcolina)30-b-poli[metacrilato de 2-(diisopropilamino)etil]60 (PMPC30-b-PDPA60), poli(óxido de etileno)100-b-poli(óxido de propileno)65-b-poli(óxido de etileno)100 (PEO100-b-PPO55-b-PEO100 ou F127), α-tiol-ω-ácido carboxílico poli(N-isopropil acrilamida)113 (HS-PNIPAM113-COOH), poli(oxido de etileno)137-b- poli(4-vinil piridina)45 (PEO137-b-P4VP43) poli(N-vinil caprolactana)94 (PNVCL94) e poli(N-vinil caprolactana)53 (PNVCL53). O tamanho das M-NPs foi determinado por espalhamento de luz (DLS) e sua morfologia comprovada através de análise de microscopia de transmissão (TEM). Sua eficiência foi posteriormente testada na catálise da redução do p-nitrofenol a p-aminofenol. Comprovou-se, mediante á ciclos reacionais, que ambos os sistemas (AuNPs e PdNPs) apresentaram capacidade de regeneração, sendo regenerado 6 vezes, provando ser um catalisador eficiente. As PdNPs foram testadas em reações de acoplamento de Suzuki.

Esta tese descreve, em dois diferentes capítulos, a síntese assimétrica da Malevamida D e a aplicação de compostos organotelúrio em reações de Suzuki-Miyaura. O primeiro capítulo refere-se ao estudo da síntese assimétrica da Malevamida D, um depsipeptídeo natural pertencente à família das dolastatinas, compostos estes com grande atividade citotóxica. As unidades DAP e MMMAH foram alcançadas em ótimos redimentos e estereosseletividades, utilizando-se reações de adição de crotil ou aliltrifluoroborato de potássio à aldeídos derivados da L-prolina e L-isoleucina, respectivamente. A elongação da cadeia da malevamida D se fez a partir de reações de esterificação e amidação; infelizmente não foi possível completar a síntese devido a problemas na última reação de acoplamento peptídico. O segundo capítulo descreve as reações entre teluretos aromáticos ou vinílicos e sais de organotrifluoroborato de potássio, mediadas por um catalisador de paládio. A partir destas reações de acoplamento cruzado tipo Suzuki-Miyaura foi possível obter-se 1,3-eninos, sistemas biarílicos, (E)- ou (Z)-estilbenos e 1,3-dienos. Todas as reações mostraram serem tolerantes a uma grande variedade de grupos funcionais e altamente estereoconservativas, nos casos envolvendo substratos vinílicos. / This thesis describes, in two different chapters, the asymmetric synthesis of malevamide D and the application of organotellurium compounds in Suzuki-Miyaura reaction. The first chapter refers to the asymmetric synthesis of malevamide D, a natural depsipeptide which belongs to the dolastatins family, and these compounds have a great interest due to theirs citotoxic activities. The DAP and MMMAH units were reached in excellent yields and stereoselectivities from 1,2-addition reaction of potassium crotyl or allyltrifluoroborate to aldehydes derivate from L-proline and L-isoleucine, respectively. The malevamide D elongation was made from reaction of esterification and amidation, unfortunately it was not possible finish the synthesis due to some problems in the last step of the total synthesis. The second chapter describes the reaction between aryl or vinyl tellurides and potassium organotrifluoroborate salts, mediated by a palladium catalyst. From this cross-coupling reaction type Suzuki-Miyaura was possible obtain 1,3-dienes, biarylic systems, (E)- or (Z)-stylbenes and 1,3-dienes. Al reactions showed to be tolerant to a wide range of functional groups and highly stereoconservative, in the cases involving vinylic substrates.