Neste trabalho estão apresentadas as estruturas cristalinas e moleculares e o estudo da estereoespecificidade de compostos de paládio com geometria de coordenação quadrado planar. Estas estruturas foram determinadas com o objetivo de verificar a relação entre a geometria e sua potencialidade como um possível agente anti-cancerígeno.<br /> No estudo de correlação através de Quimiometria foi introduzida como parâmetros a distância do átomo de paládio ao plano, que avalia o quanto o átomo de paládio esta distante do plano formado pelos seus quatro ligantes, o ângulo de ligação, onde se observa a distorção dos ângulos entre os átomos coordenados ao paládio e a superfície de van der Waals calculada para a molécula.<br /> O estudo da relação destes parâmetros mostrou que eles são suficientes para realizar a separação entre ativos e inativos, indicando para os inéditos, com estrutura estudada neste trabalho, a possível (ou não) atividade. / This work presents the crystal and molecular structures and the study of stereospecificity of palladium compounds with square planar coordination geometry. These structures were determined with the objective of verifying the relationship between the molecular geometry and its potential as a possible anti-tumor agent.<br /> In the correlation study by Chemometry, the parameters introduced were: the distance from the palladium atom to the plane, which assesses how much the palladium atom is far from the plane formed by its four ligands, the bond angle, that shows a noticeable distortion of the angles between the atoms coordinated to the palladium atom, and van der Waals surface calculated for the molecule.<br /> The relationship between these parameters showed that they are sufficient to accomplish the separation between active and inactive molecules, indicating for the novel, with structure studied in this work, the possible (or not) activity.

Made available in DSpace on 2014-06-11T19:29:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-15Bitstream added on 2014-06-13T19:38:13Z : No. of bitstreams: 1 souza_ra_me_araiq.pdf: 2538432 bytes, checksum: 3b82e3741e1179ffc530cdc631ba9c10 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho trata da síntese, caracterização estrutural e aplicações biológicas de quatro complexos de paládio(II), de fórmula trans-[PdX2(isn)2], X = Cl (1), N3 (2), SCN (3) e NCO (4), isn= isonicotinamida. Os compostos foram preparados em mistura de CHCl3/ CH3OH (1:1), partindo-se do precursor [PdCl2(CH3CN)2] que reagiu com a isn e sais de pseudohaletos: NaN3, KNCO e NaSCN. A caracterização destes complexos, no estado sólido, se deu pelas técnicas de análise elementar, espectroscopia de absorção no infravermelho, análise térmica e difração de raios X de monocristal do composto 2, possibilitando sugerir estruturas monoméricas, com a isn coordenada ao Pd pelo nitrogênio piridínico. Cloro e os pseudohaletos acham-se coordenados de modo terminal, via nitrogênio em 2 e em 4 e pelo átomo de enxofre em 3. As curvas TG substanciaram as propostas estequiométricas e permitiram estabelecer, com base na temperatura inicial de decomposição, a seguinte ordem de estabilidade térmica para esta série: trans-[PdCl2(isn)2] > trans-[Pd(SCN)2(isn)2] > trans- [Pd(NCO)2(isn)2] > trans-[Pd(N3)2(isn)2]. A estrutura do complexo 2 foi resolvida por difração de raios X de monocristal, e apresenta uma geometria quadrado-planar ao redor do Pd e estereoquímica trans. Nota-se ainda, que a estrutura se estende por ligações intermoleculares de hidrogênios, formando arranjos supramoleculares bidimensionais via N– H...O e arranjos tridimensionais, decorrentes de interações C–H...Nazida. Os dados de RMN em solução confirmam a formação dos complexos, constatando-se, além disso, a presença de outras espécies químicas em solução. A ação antiproliferativa dos compostos contra células tumorais de mama, LM3, e pulmão, LP07, foi investigada. A atividade da isn foi desprezível e os valores de IC50 dos complexos foram maiores que os apresentados pela cisplatina... / The present work deals with the synthesis, structural characterization and biological applications of four palladium(II) complexes, of formula trans-[PdX2(isn)2], X = Cl (1), N3 (2), SCN (3), and NCO (4), isn = isonicotinamide. The compounds were prepared in mixture of CHCl3/ CH3OH (1:1), from precursor [PdCl2(CH3CN)2] that reacted with isn and pseudohalide salts: NaN3, KNCO e NaSCN. The characterization of these complexes, in solid state, occurred by techniques of elemental analysis, infrared spectroscopy absorption, thermal analysis, and X-rays diffraction of single crystal of the compound 2, making possible to suggest monomeric structures containing the isn coordinated to Pd by pyridinic nitrogen. Chlorine and pseudohalides are coordinated of terminal way, by nitrogen in 2 and 4, and by sulphur atom in 3. The TG curves substantiated the stoichiometric proposals and made possible to establish, based on initial temperature of decomposition, the following order of thermal stability to this series: trans-[PdCl2(isn)2] > trans-[Pd(SCN)2(isn)2] > trans- [Pd(NCO)2(isn)2] > trans-[Pd(N3)2(isn)2]. The structure of the complex 2 was solved by Xrays diffraction of single crystal, and shows a square-planar geometry around Pd and trans stereochemistry. It is even noticed that the structure is prolonged to hydrogen intermolecular bonds, forming bidimensional supramolecular arrays by N–H...O and tridimensional arrays, resulting from C–H...Nazide interactions. NMR data in solution confirm the formation of the complexes, noticing as well as the presence of other chemical species. It was investigated the antiproliferactive action of compounds against breast tumor cells, LM3, and lung tumor cells, LP07. The activity of isn was irrelevant and IC50 values of the complexes were higher than the ones showed by cisplatin. However, the complexes showed to be more selective than cisplatin when tested... (Complete abstract click electronic access below)

Resumo: O presente trabalho trata da síntese, caracterização estrutural e aplicações biológicas de quatro complexos de paládio(II), de fórmula trans-[PdX2(isn)2], X = Cl (1), N3 (2), SCN (3) e NCO (4), isn= isonicotinamida. Os compostos foram preparados em mistura de CHCl3/ CH3OH (1:1), partindo-se do precursor [PdCl2(CH3CN)2] que reagiu com a isn e sais de pseudohaletos: NaN3, KNCO e NaSCN. A caracterização destes complexos, no estado sólido, se deu pelas técnicas de análise elementar, espectroscopia de absorção no infravermelho, análise térmica e difração de raios X de monocristal do composto 2, possibilitando sugerir estruturas monoméricas, com a isn coordenada ao Pd pelo nitrogênio piridínico. Cloro e os pseudohaletos acham-se coordenados de modo terminal, via nitrogênio em 2 e em 4 e pelo átomo de enxofre em 3. As curvas TG substanciaram as propostas estequiométricas e permitiram estabelecer, com base na temperatura inicial de decomposição, a seguinte ordem de estabilidade térmica para esta série: trans-[PdCl2(isn)2] > trans-[Pd(SCN)2(isn)2] > trans- [Pd(NCO)2(isn)2] > trans-[Pd(N3)2(isn)2]. A estrutura do complexo 2 foi resolvida por difração de raios X de monocristal, e apresenta uma geometria quadrado-planar ao redor do Pd e estereoquímica trans. Nota-se ainda, que a estrutura se estende por ligações intermoleculares de hidrogênios, formando arranjos supramoleculares bidimensionais via N- H...O e arranjos tridimensionais, decorrentes de interações C-H...Nazida. Os dados de RMN em solução confirmam a formação dos complexos, constatando-se, além disso, a presença de outras espécies químicas em solução. A ação antiproliferativa dos compostos contra células tumorais de mama, LM3, e pulmão, LP07, foi investigada. A atividade da isn foi desprezível e os valores de IC50 dos complexos foram maiores que os apresentados pela cisplatina... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present work deals with the synthesis, structural characterization and biological applications of four palladium(II) complexes, of formula trans-[PdX2(isn)2], X = Cl (1), N3 (2), SCN (3), and NCO (4), isn = isonicotinamide. The compounds were prepared in mixture of CHCl3/ CH3OH (1:1), from precursor [PdCl2(CH3CN)2] that reacted with isn and pseudohalide salts: NaN3, KNCO e NaSCN. The characterization of these complexes, in solid state, occurred by techniques of elemental analysis, infrared spectroscopy absorption, thermal analysis, and X-rays diffraction of single crystal of the compound 2, making possible to suggest monomeric structures containing the isn coordinated to Pd by pyridinic nitrogen. Chlorine and pseudohalides are coordinated of terminal way, by nitrogen in 2 and 4, and by sulphur atom in 3. The TG curves substantiated the stoichiometric proposals and made possible to establish, based on initial temperature of decomposition, the following order of thermal stability to this series: trans-[PdCl2(isn)2] > trans-[Pd(SCN)2(isn)2] > trans- [Pd(NCO)2(isn)2] > trans-[Pd(N3)2(isn)2]. The structure of the complex 2 was solved by Xrays diffraction of single crystal, and shows a square-planar geometry around Pd and trans stereochemistry. It is even noticed that the structure is prolonged to hydrogen intermolecular bonds, forming bidimensional supramolecular arrays by N-H...O and tridimensional arrays, resulting from C-H...Nazide interactions. NMR data in solution confirm the formation of the complexes, noticing as well as the presence of other chemical species. It was investigated the antiproliferactive action of compounds against breast tumor cells, LM3, and lung tumor cells, LP07. The activity of isn was irrelevant and IC50 values of the complexes were higher than the ones showed by cisplatin. However, the complexes showed to be more selective than cisplatin when tested... (Complete abstract click electronic access below) / Orientador: Antonio Eduardo Mauro / Coorientador: Adelino Vieira de Godoy Netto / Banca: Luiz Antonio Andrade de Oliveira / Banca: Denise de Oliveira Silva / Mestre

Neste trabalho estão apresentadas as estruturas cristalinas e moleculares e o estudo da estereoespecificidade de compostos de paládio com geometria de coordenação quadrado planar. Estas estruturas foram determinadas com o objetivo de verificar a relação entre a geometria e sua potencialidade como um possível agente anti-cancerígeno.<br /> No estudo de correlação através de Quimiometria foi introduzida como parâmetros a distância do átomo de paládio ao plano, que avalia o quanto o átomo de paládio esta distante do plano formado pelos seus quatro ligantes, o ângulo de ligação, onde se observa a distorção dos ângulos entre os átomos coordenados ao paládio e a superfície de van der Waals calculada para a molécula.<br /> O estudo da relação destes parâmetros mostrou que eles são suficientes para realizar a separação entre ativos e inativos, indicando para os inéditos, com estrutura estudada neste trabalho, a possível (ou não) atividade. / This work presents the crystal and molecular structures and the study of stereospecificity of palladium compounds with square planar coordination geometry. These structures were determined with the objective of verifying the relationship between the molecular geometry and its potential as a possible anti-tumor agent.<br /> In the correlation study by Chemometry, the parameters introduced were: the distance from the palladium atom to the plane, which assesses how much the palladium atom is far from the plane formed by its four ligands, the bond angle, that shows a noticeable distortion of the angles between the atoms coordinated to the palladium atom, and van der Waals surface calculated for the molecule.<br /> The relationship between these parameters showed that they are sufficient to accomplish the separation between active and inactive molecules, indicating for the novel, with structure studied in this work, the possible (or not) activity.

En plus du site de coordination interne classique des porphyrines, il est possible de fonctionnaliser le macrocycle par des sit es de coordination externes. Ce travail de thèse porte sur la fonctionnalisation de deux carbones b-pyrroliques adjacents afin d'obtenir des porphyrines conjuguées avec des ligands de type carbène N-hétérocyclique (CNH).Les CNHs présentent de remarquables propriétés électroniques qui en font aujourd'hui des ligands incontournables en catalyse et en chimie organométallique. L'objectif de ce travail de thèse a été d'étudier l'influence de la porphyrine sur les propriétés électroniques du ligand périphérique CNH, et de moduler les propriétés électroniques et catalytiques de complexe métalliques en fonction des modifications chimiques apportées à la porphyrine, à savoir sa métallation ou la protonation des azotes de la porphyrine base-libre.Dans un premier temps, les différentes méthodes de synthèse développées afin d'obtenir différents sels d'imidazolium conjugués avec le macrocycle porphyrinique sont développées. Ces sels d'imidazolium sont les précurseurs des ligands porphyrine-CNH. Afin d'étudier les propriétés catalytiques de complexes contenant des ligands de type porphyrine-CNH, plusieurs complexes de palladium(II) ont été synthétisés et caractérisés. Les études des propriétés catalytiques de ces complexes testées sur le couplage de Heck ont démontré que de bien meilleures activités catalytiques étaient observées si les porphyrines contiennent un cation métallique. Enfin, les propriétés des ligands CNH ont été étudiées sur des complexes de types (CNH)Rh(COD)X et (CNH)Rh(CO)2X avec X = I ou Cl. / In addition to the usual inner coordination site of porphyrins, it is possible to functionalize the macrocycle by external coordination sites. This PhD thesis is devoted to the functionalization of two neighboring b-pyrrolic carbons in order to obtain porphyrins fused to peripheral N-heterocyclic carbene ligands (NHC).NHC ligands are known to display outstanding electronic properties which render them important ligands in the fields of catalysis and organometallic chemistry. The aim of this PhD work was to study the influence of the porphyrin on the electronic properties of the peripheral NHC ligand, and to modulate the electronic and catalytic properties of anchored metal complexes according to the chemical modifications brought to the porphyrin, ie. its metallation or the protonation of the free-base porphyrin.Firstly, the different synthetic procedures to obtain porphyrins fused to imidazolium rings were developed. These imidazolium salts are the key precursors of the porphyrin-NHC ligands. In order to study the catalytic properties of metal complexes containing porphyrin-NHC ligands, several palladium(II) complexes were synthesized and characterized. The study of the catalystic properties of these complexes showed that better catalytic activities were observed if the porphyrins contain a metal cation. Then, the electronic properties of these NHC ligands were evaluated for (NHC)Rh(COD)X and (NHC)Rh(CO)2X complexes with X = I or Cl.

Diimidazolium salts featuring different bridges between the imidazolium groups, as well as electron-withdrawing groups (chloride, cyanide) at the 4- and 5-position of the heterocyclic rings, have been successfully prepared. The diimidazolium salts serve as convenient precursors of di(N-heterocyclic carbene) ligands, which coordinate in a chelating fashion to palladium(II) centres. The effect of the newly introduced electron-withdrawing groups on the spectroscopic and structural characteristics of the resulting complexes as well as on their reactivity as catalysts in a model alkyne hydroarylation reaction has been investigated and is discussed herein.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

Dans le premier chapitre, nous avons synthétisé les premiers phosphino(silyl)carbènes optiquement purs, à partir de la (R,R)- et de la (S,S)-N-N'- ditertiobutyl-1-1,2-éthanediamine. Ces carbènes ont ensuite été impliqués dans des réactions de cyclopropanation asymétriques, conduisant à d'excellents excès diastéréoisomériques, puisque supérieurs à 98%. Préalablement d'autres diamines précurseurs avaient été utilisées, sans succès, démontrant ainsi une fois de plus, l'importance de l'encombrement stérique dans la stabilisation des carbènes singulets. En effet la photolyse du dérivé diazoïque de la trans-N-N'-diisopropylcyclohexane -1,2-diamine ne conduit pas au carbène correspondant mais à un 1,3 -diphosphète, dimère "tête-queue" du carbène attendu. De même la photolyse du dérivé diazoïque de la N-N' -diisopropyl- 1,2 éthanediamine ne conduit pas au carbène correspondant mais à un cycle à 6 chaînons original, correspondant à l'addition d'une molécule de précurseur diazoïque sur le carbène attendu. La réactivité originale de ce phosphino(sylil)diazométhane a d'ailleurs été plus largement étudiée et est présentée dans ce document.<br />Dans le deuxième chapitre, est présentée l'étude de la réactivité des phosphino(amino)carbènes. Ce type de carbènes, découvert récemment au sein de notre laboratoire par Nathalie Merceron-Saffon, est une molécule bi fonctionnelle, présentant une fonction carbénique et une fonction phosphine. Nous avons exploité la réactivité de la paire libre de la phosphine pour réaliser la synthèse de nouveaux phosphonio(amino)carbène par oxydation du phosphore. Une étude sur les propriétés acido-basique de ce carbène a ensuite est menée, ouvrant ainsi une nouvelle voie à la synthèse en une seule étape de dérivés propargyliques par réaction d'un phosphino(amino)carbène avec l'acétone ou l'acétonitrile. Enfin ce carbène a été utilisé comme ligand bidentate du palladium et du nickel. Le complexe de palladium (II) obtenu a alors été testé en catalyse pour la réaction d'amination d'aryle. Les résultats obtenus (90% de conversion en 2h) sont encourageants.<br />Dans le troisième chapitre, nous avons cherché à synthétiser de nouveaux modèles de diphosphinocarbènes cycliques, analogues des NHCs et découverts très récemment au sein de notre laboratoire par David Martin. Dans un premier temps, l'importance cruciale de l'encombrement stérique dans la stabilisation des carbènes singulets a été une nouvelle fois illustrée, puisque la synthèse du diphosphinocarbène présentant un groupement tertiobutyle sur les phosphores s'est révélée impossible, validant ainsi une étude théorique réalisée précédemment par W.W. Schoeller. Dans un deuxième temps, nous avons synthétisé un nouveau modèle de diphosphinocarbène cyclique complexé à GaCl3. Il a été obtenu par déprotonation du diphosphino-carbocation correspondant, synthétisé par piégeage d'un phosphénium par la dimétyl-cyanamide.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

This thesis describes research efforts dedicated to the development of palladium(II)-catalyzed oxidative Heck and Heck/Suzuki domino reactions, and the applications of a new microwave heating technology, purpose-built for continuous flow in organic synthesis. Paper I describes the development of a ligand-modulated approach for attaching aryl groups to a chelating vinyl ether. By switching the ligand being used, selectivity for the arylation could be shifted to obtain three different outcomes: internal α- or terminal β-arylation, as well as a serendipitously discovered domino α,β-diarylation process. The latter was proposed to be an effect of para-benzoquinone, effectively acting as a stabilizing π-acidic ligand with the ability to suppress β-hydride elimination. Paper II explores the performance of a new microwave heating technology in combination with continuous flow. The novel nonresonant microwave applicator allowed rapid heating of common laboratory solvents and reaction mixtures above their boiling points with stable and reproducible temperature profiles. The technology was successfully applied to small-scale method development and subsequent scale-out of palladium-catalyzed reactions, heterocycle synthesis and classical organic transformations such as the Fischer indole synthesis. Paper III focuses on developing regioselective oxidative decarboxylative Heck reactions with electron-rich olefins. Successful internal α-arylations were achieved using various olefins and ortho-substituted aromatic acids. The mechanism was also studied by ESI-MS analysis. Key cationic organopalladium intermediates were identified, as well as an unexpected palladium(II)-complex which was isolated and characterized. Its experimentally deduced structure was in accordance with the lowest energy minimum found by DFT calculations. Preliminary findings suggested that the complex acts as a catalyst trap. Paper IV studies the mechanism of the reaction in Paper III by means of DFT calculations. Reductive elimination was identified as the rate-determining step when using a linear enamide as the olefin, due to its propensity to form low energy chelates. Its chelating properties also played a key role in the stability of the isolated palladium(II)-complex. The complex, which can act as a catalyst trap, was characterized by X-ray crystallography.