Dissertations / Theses on the topic 'Palladacycles'

Le travail présenté dans ce memoire a été realisé au Laboratory of Molecular Catalysis (Chapitre 1, 2 et 3) de l'Universidade Federal do Rio Grande do Sul, sous la direction du Prof. Jaïrton Dupont, et au Laboratoire de Synthèse Métallo Induites (Chapitre 4) de l'Université de Strasbourg, sous la direction du Dr. Michel Pfeffer, entre le mois d'Aoüt 2006 et le mois de Décembre 2009. Le présent travail décrit la synthese et la caracterisation de nouvelles molecules п-extensibles contenant le noyau 2,1,3-benzothiadiazole (BID) et ses derives. Nous avons fait ('extension п des positions 4 et 7 de la BTD en utilisant les reactions de Suzuki et Sonogashira avec de bons rendements. Nous avons aussi bien caracterise ces nouveaux composes et etudie leurs caracteristiques electrochimiques et photophysiques. Nous avons étudié ('application des derives non symetriques de la BTD pour ('intercalation avec l'ADN. Pour les tests avec l'ADN, nous avons choisi trois composes ayant pour caractéristique commune un noyau BTD portant un groupe 4- methoxyphenyle, et dont nous avons fait varier la nature du substituant en position 7 : pyridine (2 et 3-pyridine) ou phenyle. Ces molécules ont donné d'excellents résultats lors de l'étude de leurs propriétés d'intercalation et de leurs propriétés photophysiques. Des nouvelles molécules cyclométallées ont été obtenues par la réaction des dérivés BTD avec l'acetate de palladium. Une série de complexes cyclopallades a pu être préparée avec de très bons rendements, sans que I'atome de soufre n'interagisse avec le metal. II est remarquable qu'il s'agisse de metallacycles a 6 chainons, moins courants que ceux a 5 chaînons. Tous les complexes ont 6t6 completement caractériéss, notamment par analyse élémentaire et par spectroscopie RMN, IR et UV-visible. Certains d'entre eux ont cristallises, et les monocristaux correspondants ont été analysés par diffraction des Rayons-X.<br>The present work was carried out at the Laboratory of Molecular Catalysis (Chapters 1, 2 and 3) in the Universidade Federal do Rio Grande do Sul, under supervision of Prof. JaIrton Dupont, and at the Laboratoire de Syntheses Metallo Induites (Chapter 4) at the Universite de Strasbourg, under supervision of Prof. Michel Pfeffer, between August 2006 and December 2009. In this work we describe the synthesis and characterisation of new Tr-extended molecules with the 2,1,3-benzothiadiazole core and their derivatives. We have performed the u extension of 4 and 7 positions of the BTD core employing Suzuki and Sonogashira reaction with good yields. The new molecules were fully characterized and their electrochemical and photophysical properties were investigated. Intercalation of the non symmetrical BTD derivatives and DNA were studied. Three molecules were chosen for testing the DNA intercalation, all compounds with the 4-methoxyphenyl group as the common ligand bound to one side of BTD core and a pyridine (2- or 3-pyridine) or a phenyl to the other side. We obtained excellent results for the intercalation and photophysical properties. New cyclometallated compounds were obtained by the reaction of palladium acetate and the BTD derivatives. A series of cyclopalladated compounds were synthesized with good yields with no interaction between the metal and sulphur atom. The remarkable characteristic of these cyclometallated compounds is the formation of 6 member rings, less commons than 5 members rings. All compounds were fully characterized by elemental analysis and NMR spectroscopy, IR and UV-Vis. Some complex were crystallized and analyzed by X-Ray diffraction.

Le travail présenté dans ce mémoire a été réalisé au Laboratory of Molecular Catalysis (Chapitre 1, 2 et 3) de l'Universidade Federal do Rio Grande do Sul, sous la direction du Prof. Jaïrton Dupont, et au Laboratoire de Synthése Métallo Induites (Chapitre 4) de l'Université de Strasbourg, sous la direction du Dr. Michel Pfeffer, entre le mois d'Août 2006 et le mois de Décembre 2009. Le présent travail décrit la synthèse et la caractérisation de nouvelles molécules TT-extensibles contenant le noyau 2,1 ,3-benzothiadiazole (BTD) et ses dérivés. Nous avons étudié l'application des dérivés non symétriques de la BTD pour l'intercalation avec l'ADN. Pour les tests avec l'ADN, nous avons choisi trois composés ayant pour caractéristique commune un noyau BTD portant un groupe 4-méthoxyphényle, et dont nous avons fait varier la nature du substituant en position 7: pyridine (2 et 3-pyridine) ou phényle. Ces molécules ont donné d'excellents résultats lors de l'étude de leurs propriétés d'intercalation et de leurs propriétés photophysiques. Des nouvelles molécules cyclométallées ont été obtenues par la réaction des dérivés BTD avec l'acétate de palladium. Une série de complexes cyclopalladés a pu être préparée avec de très bons rendements, sans que l'atome de soufre n'interagisse avec le métal. Il est remarquable qu'il s'agisse de métallacycles à 6 chaînons, moins courants que ceux à 5 chaînons. Tous les complexes ont été complètement caractérisés, notamment par analyse élémentaire et par spectroscopie RMN, IR et UV-visible. Certains d'entre eux ont cristallisés, et les monocristaux correspondants ont été analysés par diffraction des Rayons-X<br>The present work was carried out at the Laboratory of Molecular Catalysis (Chapters 1,2 and 3) in the Universidade Federal do Rio Grande do Sul, under supervision of Prof. Jaïrton Dupont, and at the Laboratoire de Synthèses Métallo Induites (Chapter 4) at the Université de Strasbourg, under supervision of 1 Prof. Michel Pfeffer, between August 2006 and December 2009. ) ln this work we describe the synthesis and characterisation of new TT-extended molecules with the 2,1 ,3-benzothiadiazole core and their derivatives. We have performed the TT extension of 4 and 7 positions of the BTD core employing Suzuki and Sonogashira reaction with good yields. The new molecules were fully characterized and their electrochemical and photophysical properties were investigated. Intercalation of the non symmetrical BTD derivatives and DNA were studied. Three molecules were chosen for testing the DNA intercalation, ail compounds with the 4-methoxyphenyl group as the common ligand bound to one side of BTD core and a pyridine (2- or 3-pyridine) or a phenyl to the other side. VJ. E obtained excellent results for the intercalation and photophysical properties. New cyclometallated compounds were obtained by the reaction of palladium acetate and the BTD derivatives. A series of cyclopalladated compounds were synthesized with good yields with no interaction between the metal and sulphur atom. The remarkable characteristic of these cyclometallated compounds is the formation of 6 member rings, less commons than 5 members rings. Ali compounds were fully characterized by elemental analysis and NMR spectroscopy, IR and UV-Vis. Sorne complex were crystallized and analyzed by X-Ray diffraction

Thesis (Ph. D.)--University of Nevada, Reno, 2007.<br>"May, 2007." Includes bibliographical references. Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2008]. 1 microfilm reel ; 35 mm. Online version available on the World Wide Web.

This thesis is concerned with the use of palladacyclic complexes as catalysts for C-C and C-heteroatom bond-forming reactions in which an oxidation state change of the metal centre is not part of the catalytic cycle. To this end, the investigation of a range of known K²-C,L-based palladacycles in the allylation of aldehyde and imine substrates using stannanes, as well as the 1,4-conjugate arylation of enones and imines using arylboronic acids under mild conditions is described. In each case the commercially available phosphite-based dimeric palladacycle is found to be the most active complex capable of achieving excellent conversions (>90%) at the 0.5 - 2.5mol% loading range. Three previously unknown phosphinite and amidophosphinite palladium pincer complexes are also synthesised, characterised (including crystallographically) and tested in the 1,4-conjugate addition of phenylboronic acid to chalcone and found to be inactive.

This thesis presents a detailed theoretical/computational analysis using quantum chemistry to investigate the thermochemistry and reaction mechanisms of palladacycles that underpin experimental observations. The thesis begins by establishing a suitable computational methodology for the study of pincer palladacycles. It was found that Density Functional Theory (DFT) was suitable for the accurate reproduction of geometric structures and energetics by comparing a range of commonly used density functionals and basis sets with the X-ray crystal structures of symmetric pincer palladacycles. The detailed electronic structure of several pincer palladacycles was investigated using Complete Active Space Self-Consistent Field method (CASSCF) and it was shown that the dominant configuration was larger than 0.96, indicating that the ground state electronic structure has significant single-reference character. DFT was used to investigate the stability of symmetrical pincer palladacycles, and then by changing the donor ligand, unsymmetrical pincer palladacycles. The pincer palladacycle formation was investigated and it was found that the barrier to C-H activation was dependent on the ligand arm of the pincer that coordinates to PdCl2. Topological analysis was performed using Quantum Theory of Atoms In Molecules (QTAIM) for determining the strength and nature of the Pd and donor atom interactions, showing that the bond strength depends on the type of donor atom and trans influence in the pincer palladacycles. The mechanism for Pd(0) formation from both symmetrical and unsymmetrical pincer palladacycle pre-catalysts for catalysis in Suzuki-Miyaura carbon-carbon cross-coupling reactions was studied, and then with the introduction of base and the effect of solvent. It was shown that the key steps are transmetallation and reductive elimination processes, and differences in the overall Gibbs free energy and transmetallation barrier provide an explanation for observed catalytic activity. This has been in conjunction with experimental chemists. Finally, the functionalisation of benzodiazepines was investigated in three conditions; with Pd(II)/Ru(II)-catalysts, with Pd(II)-catalysts and without catalyst. It was found that the Ru(II) photocatalyst with Pd(II)-catalyst is the best condition for functionalisation on benzodiazepines with the lowest energy barrier.

This thesis presents the synthesis of a number of unsymmetrical SCN, N'CN, PCN and PCS pincer palladacycles. A new synthetic route has been designed towards unsymmetrical pincer ligands, involving a key Suzuki-Miyaura coupling, yielding the characteristic biaryl ligand backbone presented. New unsymmetrical SCN pincer ligands, containing a pyridine and a thioether ligand were synthesised. A number of substituents were used on the thioether ligand arm, with various steric demand and electron donating characteristics. These unsymmetrical ligands underwent C-H bond activation with palladium (II) salts, yielding the corresponding palladacycles. In order to investigate the effect of changing the sulphur donor atom, the thioether ligand arm was replaced by amines in the synthesis of N'CN pincer palladacycles, and phosphinites in the synthesis of PCN pincer palladacycles. Also changing the pyridine donor arm to a thioether was investigated, yielding a PCS pincer palladacycle. The palladacycles were tested in a number of catalytic applications: Suzuki-Miyaura coupling of sterically demanding and electronically deactivated aryl bromides; cross coupling of arylboronic acids and vinyl epoxides; and catalytic aldol condensations; revealing differences between the SCN, N'CN and PCN pincer palladacycles. In order to investigate the differences in catalytic activity, density functional theory was employed. A palladacycle formation pathway containing a key C-H bond activation step was investigated for an SCN pincer palladacycle, revealing differences in energy barriers of the C-H bond activation step depending on whetherthe thioether or the pyridine arm coordinates to the PdCl2 first. Next, the activation pathway of the palladacycles in the Suzuki-Miyaura coupling reaction was studied, identifying key transmetallation and reductive elimination steps. Differences in the overall thermodynamics and kinetics provide explanations for differences in catalytic activity. The results show that slower release of the catalytically active Pd(0) species yield a better precatalyst in the Suzuki-Miyaura coupling reaction, due to the lower propensity to form catalytically inactive palladium black. Overall this thesis provides a novel synthetic route to a family of unsymmetrical pincer palladacycles; their testing in catalytic activity in several applications, revealing differences in catalytic activity; and a theoretical study into key mechanisms, C-H bond activation, and catalyst activation in the Suzuki-Miyaura coupling reaction, which provide a rationalisation to the varying catalytic activities of the unsymmetrical pincer palladacycles.

1. OBJETIVOS Los paladaciclos son objeto de un enorme interés dentro de la química organometálica debido a su gran estabilidad, a la posibilidad de modular su reactividad y a sus numerosas aplicaciones en diferentes áreas, como medicina, ciencia de materiales o síntesis orgánica. A pesar de los numerosos C,N-paladaciclos que se conocen conteniendo iminas o aminas terciarias, son escasos los derivados que contienen arilalquilaminas primarias y, por ello, su reactividad se encuentra escasamente explorada. De acuerdo con estos antecedentes, se han propuesto los siguientes objetivos: 1. Preparar nuevos paladaciclos de seis miembros conteniendo fenetilaminas primarias con relevancia biológica, como son el éster metílico de la L-tirosina (derivado de un aminoácido natural) y la homoveratrilamina (perteneciente a la familia de las anfetaminas con propiedades alucinógenas,). 2. Sintetizar y caracterizar nuevos alquil- y alquenil-paladaciclos de ocho miembros, mediante la inserción de alquenos y alquinos en el enlace Pd–C de los metalaciclos de seis miembros derivados de estas arilalquilaminas. 3. Obtener paladaciclos de ocho, nueve, diez y once miembros mediante la inserción secuencial de dos o tres moléculas insaturadas en el enlace Pd–C de los metalaciclos de seis miembros. 4. Estudiar las aplicaciones en síntesis orgánica de estos procesos de inserción secuencial, explorando las reacciones de descomposición de los intermedios organometálicos para generar nuevos N-heterociclos o derivados orto-funcionalizados de las arilalquilaminas de partida. 5. Caracterizar estructuralmente todos los compuestos preparados (orgánicos y organometálicos), dedicando especial atención a la influencia de los grupos NH o NH2 en la formación de estructuras supramoleculares mediante la formación de puentes de hidrógeno. 2. METODOLOGÍA Por reacción de Pd(OAc)2 con los triflatos de amonio derivados del éster metílico de la L-tirosina y de la homoveratrilamina se prepararon los paladaciclos de seis miembros correspondientes. A partir de ellos, se hicieron reacciones de inserción en el enlace Pd–C de: a) CO, b) RNC, c) alquenos terminales y d) alquinos internos, incluyendo el bencino. También se ensayaron las reacciones de inserción secuencial de: a) alqueno/CO, b) alquino/CO, c) bencino/bencino y bencino/bencino/CO o RNC. En muchos casos, se aislaron los intermedios organometálicos de las reacciones de inserción que, en las condiciones apropiadas, pueden descomponerse para dar los derivados orgánicos y Pd(0). Todos los compuestos preparados se han caracterizado completamente mediante espectroscopia IR y de RMN y por análisis elemental o espectroscopia de masas. Adicionalmente, algunos compuestos han sido caracterizados por estudio de difracción de rayos X. 3. RESULTADOS O CONCLUSIONES 1) Se ha puesto a punto un nuevo método general de ortometalación de arilalquilaminas que permite obtener paladaciclos de seis miembros conteniendo fenetilaminas primarias o secundarias. Este método ha sido aplicado con éxito a la síntesis de algunos precatalizadores preparados anteriormente por el Prof. Buchwald y que tienen interés comercial. Dentro de las arilalquilaminas estudiadas se encuentran la homoveratrilamina y el éster metílico de la L-tirosina. La reacción de los paladaciclos derivados de estas aminas con CO da lugar a las correspondientes tetrahidroisoquinolonas, una de las cuales es un alcaloide natural denominado Coridaldina. 2) Los complejos orto-paladiados derivados de la homoveratrilamina experimentan la inserción regioselectiva de alquenos o de alquinos (incluyendo bencino) en el enlace Pd–C para dar alquil- o alquenil-paladaciclos estables de ocho miembros. El complejo derivado de la inserción de bencino es el primer metalaciclo aislado obtenido por carbopaladación directa de un arino. Mediante reacciones de inserción secuencial de dos o tres moléculas inaturadas en el enlace Pd–C, se han preparado paladaciclos estables de ocho, nueve, diez y once miembros, que pueden descomponerse para dar interesantes derivados orgánicos<br>1. OBJECTIVES Cyclopalladated compounds contain a Pd–C -bond stabilized by the coordination of a heteroatom of the ligand. They constitute one of the most studied types of organopalladium derivatives, because they combine the reactivity of the Pd–C bond with a remarkable stability. These compounds have found applications in many different fields, such as pharmacology, material science and catalysis. Although C,N-palladacycles containing imines or tertiary amines are well known, those derived from primary arylalkylamines are scarce. According to these antecedents, we aimed at the following goals: 1. To expand the library of ortho-metalated primary arylalkylamines, preparing new six-membered palladacycles containing phenethylamines with biological importance, such as homoveratrylamine (pharmaceuticals) or L-tyrosine methyl ester (natural -amino acids). 2. To synthesize and characterize new eight-membered alkyl- and alkenyl-palladacycles through the insertion of terminal alkenes and alkynes into the Pd–C bond of six-membered metallacycles derived from those primary arylalkylamines. 3. To obtain enlarged palladacycles (larger than eight-membered) through the sequential insertion of two or three unsaturated molecules into the Pd–C bond of six-membered metallacycles. 4. To study the applicability of these processes in organic synthesis, exploring the decomposition reactions of the organometallic intermediates to generate new N-palladacycles or ortho-functionalized derivatives of the primary arylalkylamines used as starting materials. 5. To characterize structurally all the compounds prepared (both organometallic and organic), dedicating special attention to the influence of the NH or NH2 groups in the formation of supramolecular structures. 2. METHODOLOGY The reaction of Pd(OAc)2 with the triflate salts derived from homoveratrylamine and L-tyrosine methyl ester lead to the corresponding six-membered palladacycles. These metallacycles insert unsaturated molecules into the Pd–C bond to afford enlarged palladacycles that decompose under the appropriate conditions to give interesting N-heterocycles. The following substrates have been tried: a) CO, b) RNC, c) alkenes, d) internal alkynes, including benzyne, e) alkenes/CO, f) alkynes/CO, g) benzyne/benzyne and h) benzyne/benzyne/CO or RNC. All the new compounds reported in this Thesis have been completely characterized by NMR, IR and elemental analysis or HRMS. Some of them have also been characterized by X-ray diffraction studies. 3. RESULTS OR CONCLUSIONS 1) We have reported a new, efficient, flexible and inexpensive method to prepare chloro-, bromo- and iodo-complexes of Pd(II) containing ortho-metalated primary or secondary phenethylamines. This procedure has been applied to the synthesis of Buchwald-type precatalysts and the ortho-palladated complexes derived from homoveratrylamine and L-tyrosine methyl ester, both biologically relevant arylalkylamines. These cyclopalladated complexes can be used as intermediates in organic synthesis, as proved by the fact that their reactions with CO render the corresponding tetrahydro-isoquinolones. One of the prepared tetrahydro-isoquinolones is the natural alkaloid Corydaldine. 2) The ortho-palladated complex derived from homoveratrylamine undergoes the regioselective insertion of alkenes (ethyl acrylate, methyl vinyl ketone, 2-norbornene) or alkynes (diphenylacetylene, methyl phenylpropiolate, 1-phenyl-1-propyne and benzyne) into the Pd–C bond, leading to stable eight-membered alkyl- or alkenyl-palladacycles. The derivative arising from the insertion of benzyne is the first isolated metallacycle obtained by direct carbopalladation of an aryne. This last palladacycle can further react with another molecule of benzyne to give an enlarged ten-membered palladacycle. This is the first time that the intermediates of the sequential carbopalladation of two molecules of benzyne and RNC insertion have been isolated.

Im ersten Teil der Arbeit wird die Synthese neopentyl- und neosilylsubstituierter Phosphane zur Verwendung als Liganden in katalytisch aktiven Palladiumkomplexen beschrieben. Die Aktivität wurde in der Suzuki-Miyaura Kreuzkupplungsreaktion getestet. Während die neosilylsubstituierten Phosphane 2:1 Addukte (5b und 5d) mit geeigneten Palladiumsalzen bilden, welche moderate Katalyseaktivität zeigen, untergehen die neopentylsubstituierten Komplexe schnelle Cyclometalierungsreaktionen in Gegenwart von Basen und bilden die katalytisch wenig aktiven Palladacyclen (6a, 6e, and 6g). Die deaktivierende Cylometallierung konnte durch Darstellung der Palladiumcomplexe ausgehend von Pd(cod)Cl2 in Abwesenheit von Basen vermieden werden. Die erhaltenen 2:1 Phosphaneaddukte zeigten deutlich verbesserte Aktivität. Daraus wurde geschlossen, dass die Cyclomettalierung als Nebenreaktion eine wichtige Deaktiverungsmöglichkeit darstellt, diese Überlegung veranlasste uns Trialkylphosphane mittlerer Größe, mit Substituenten die nur schwer eine Cyclometallierungen eingehen können zu testen. Die Verwendung der Phosphoniumsalze 4h (R = Cy, R‘ = neopentyl) und 4m (R = iPr, R‘ = CH2Cy) führt zu höheren Aktivitäten in der Suzuki-Miyaura Kreuzkupplung, als bestes Katalysatorsystem hat sich die Kombination aus Pd2(dba)3 oder Pd(OAc)2 und entsprechendem Phosphoniumsalz ergeben. Im zweiten Teil dieser Arbeit werden Synthesen zu neuen biphenylbasierten Diphosphanen (70, 71, 76, and 77) vorgestellt. Die Palladiumkomplexe wurden ebenfalls auf ihre Eignung als Katalysatoren in palladiumkatalysierten Suzuki-Miyaura Kreuzkupplungen getestet und zeigen für diese Klasse von Komplexen gute Aktivität. Das Tetraphosphan 82 wurde für die Synthese des zweikernigen Palladium(II)-komplex 83 eingesetzt. Durch die Koordination des D2h-symmetrischen Tetraphosphanes an die Palladiumatome wird die Symmetrie des Moleküls erniedrigt und folglich erhält man den formal D2-symmetrischen Komplex 83<br>In the first part of this thesis, the synthesis and catalytic activity of neopentyl and neosilyl substituted phosphine palladium complexes is described. The complexes have been tested in the Suzuki-Miyaura cross-coupling reaction. Whereas the neosilyl substituted phosphines form 2:1 adducts (5b and 5d) with Palladium salts which showed moderate activity, the neopentyl complexes quickly undergo cyclometallation in presence of bases to form Palladacycles (6a, 6e, and 6g) which showed only moderate catalytic activity. Cyclometallation could be avoided by the preparation starting from Pd(cod)Cl2 in the absence of bases. The obtained 2:1 phosphine adducts showed superior activity. We concluded that cyclometallation process is an important deactivation pathway, this prompted us to test trialkyl phosphine ligands with medium size but substituents not reliable to cyclometallation. We have been pleased to find that 4h (R = Cy, R‘ = neopentyl) and 4m (R = iPr, R‘ = CH2Cy) showed good activity in the Suzuki-Miyaura cross-coupling reaction. The best results have been obtained by in situ preparation of active catalyst from Pd2(dba)3 or Pd(OAc)2 and the appropriate phosphonium salt. In the second part of this thesis, the first synthesis of a new family of biphenyl based bisphosphine ligands (70, 71, 76, and 77) has been reported. Their palladium complexes were successfully tested as catalyst in the Suzuki cross-coupling reaction. Within the class of bisphosphine based palladium complexes they show good activity in Suzuki-Miyaura cross-coupling reaction. Systematically, was expanded our synthesis strategy and we were able to introduce the first synthesis of a highly symmetric 2,2',6,6'-tetraphosphinobiphenyl. Tetraphosphine 82 was used as ligand in a dinuclear palladium(II) complex 83. Upon complexation the D2h symmetric 2,2’,6,6’-tetraphosphine lead to a chiral D2 symmetric complex 83

Epilepsy is a neurological disease that affects approximately 50 million people worldwide and is related to oxidative stress, which plays an important role in the neuronal damage induced by seizures. The current drugs used in the treatment of this disease have their use often limited due to their adverse effects; moreover, approximately 30% of epileptic patients who are receiving drug treatment are not totally free of seizures. These facts motivated the development of this work that aims to synthesize, characterize and evaluate palladium(II) complexes derived from diazepam in order to obtain complexes that can be used to treat epilepsy. In this work were synthesized five complexes of diazepam-palladium(II): two in dimeric form (DIAZPdOAcD and DIAZPdClD) and three in monomeric form (DIAZPdOAcPPh3, DIAZPdClPPh3 and DIAZPdClPy). All these complexes were characterized by spectrometric techniques and elemental analysis; the monomer DIAZPdOAcD had your chemical structure elucidated by X-ray diffraction. In addition, all complexes were evaluated for anticonvulsant and antioxidante activities and for citotoxicity. Through the characterization techniques used in this work it was possible to confirm the formation of all the complexes; it is important to noted that the X-ray diffraction study of DIAZPdOAcD showed the distorted square-planar geometry of palladium(II), the occurrence of cyclopalladation and the open-book shape of this dimer. Regarding the anticonvulsant and antioxidante activities, it was observed that only the DIAZPdOAcD dimer presented significant results. With respect to cytotoxicity, all complexes showed more pronounced toxicity when compared to diazepam. However, the anticonvulsive effect and the potential neuroprotective effect performed by DIAZPdOAcD should be emphasized, since they are important characteristics of new drugs for the treatment of epilepsy.<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>A epilepsia é uma doença neurológica que afeta aproximadamente 50 milhões de pessoas em todo o mundo e está relacionada ao estresse oxidativo, que desempenha um importante papel no dano neuronal induzido por convulsões. Os fármacos atuais utilizados no tratamento desta doença apresentam seu uso frequentemente limitado devido aos seus efeitos adversos; além disso, aproximadamente 30% dos pacientes epiléticos que estão recebendo tratamento medicamentoso não ficam totalmente livres de convulsões. Tais fatos motivaram o desenvolvimento deste trabalho que apresenta como objetivo sintetizar, caracterizar e avaliar complexos de paládio(II) derivados do diazepam com a finalidade de obter complexos que possam ser utilizados para o tratamento da epilepsia. Neste trabalho foram sintetizados cinco complexos de paládio(II) derivados do diazepam: dois na forma dimérica (DIAZPdOAcD e DIAZPdClD) e três na forma monomérica (DIAZPdOAcPPh3, DIAZPdClPPh3, e DIAZPdClPy). Todos esses complexos foram caracterizados por técnicas espectrométricas e análise elementar; e o dímero DIAZPdOAcD teve sua estrutura química elucidada através de difração de raios X. Além disso, todos os complexos foram avaliados quanto às atividades anticonvulsivante e antioxidante e à citotoxicidade. Através das técnicas de caracterização utilizadas neste trabalho foi possível confirmar a formação de todos os complexos; cabe destacar que por meio do estudo de difração de raios X do DIAZPdOAcD observou-se a geometria quadrada plana distorcida do paládio(II), a ocorrência da ciclopaladação e a forma de livro aberto deste dímero. Com relação às atividades anticonvulsivante e antioxidante, observou-se que somente o dímero DIAZPdOAcD apresentou resultados significativos. No que se refere à citotoxicidade, todos os complexos apresentaram uma maior toxicidade quando comparados ao diazepam. No entanto, cabe salientar o efeito anticonvulsivante e o potencial efeito neuroprotetor desempenhados pelo DIAZPdOAcD, pois são características importantes de novos fármacos para o tratamento da epilepsia.

OBJETIVOS Esta tesis describe la síntesis y el estudio de la reactividad de complejos arílicos de paladio con un grupo amida en posición orto frente a moléculas insaturadas, con el principal objetivo de explorar rutas sintéticas para nuevos compuestos orgánicos, en particular, compuestos heterocíclicos. Se emplean ligandos arílicos con la función amida directamente enlazada al anillo aromático (benzamidas ortopaladiadas) o conectada a través de uno o dos grupos metileno (fenilacetamidas o 3-fenilpropanamidas ortopaladiadas). Este estudio ha permitido la síntesis de una serie de nuevos paladaciclos y heterociclos de diferentes tamaños (5, 6, 7, 8 ó 9 miembros). METODOLOGÍA La metodología utilizada consta de las siguientes etapas: (1) síntesis de nuevos complejos arílicos de paladio y derivados C,O- y C,N-paladacíclicos; (2) inserción de CO o isocianuros en el enlace Pd-C y optimización de las condiciones de reacción para obtener productos heterocíclicos; (3) inserción de alquinos en el enlace Pd-C de C,O-paladaciclos y caracterización de los paladaciclos agrandados resultantes; (4) inserción de CO o isocianuros en el enlace Pd-C de los paladaciclos agrandados para obtener heterociclos de mayor tamaño. RESULTADOS Se ha sintetizado una serie de complejos del tipo yodo(aril)paladio(II) por adición oxidante de 2-yodobenzamidas, 2-yodofenilacetamidas o 3-(2-yodofenil)propanamidas, a Pd(0) en presencia de un ligando quelatante N^N. Las reacciones de estos complejos con triflato de plata conducen a la abstracción del ligando yoduro y la formación de C,O-paladaciclos catiónicos de cinco, seis, o siete miembros, en los que la función amida se coordina a través del átomo de oxígeno. Por otro lado, amidatos C,N-paladacíclicos de cinco, seis o siete miembros se han obtenido por desprotonación de la función amida (derivados con los grupos NH2 o NHMe). La inserción de CO o isocianuros en el enlace Pd-C de benzamidas ortopaladiadas desencadena un rápido acoplamiento reductor C-N (derivados con los grupos NH2 o NHMe), dando lugar a la formación de isoindolin-1,3-dionas (ftalimidas) o 3 iminoisoindolin-1-onas. Estas reacciones conllevan la desprotonación de grupos NH2 o NHMe. Pueden tener lugar acoplamientos reductores C-N y/o C-O intramoleculares tras la inserción de CO o XyNC en el enlace Pd–C de fenilacetamidas ortopaladiadas, dependiendo de los sustituyentes sobre el nitrógeno amídico, conduciendo a heterociclos derivados de la isoquinolina o la isocumarina. Los acoplamientos C–O conllevan la desprotonación del grupo -CH2 y son los primeros acoplamientos C–O mediados por paladio descritos que implican una función amida. Las reacciones de las 3-fenilpropanamidas ciclopaladiadas con CO o XyNC han permitido la síntesis de imidas cíclicas de siete miembros y una iminobenzazepinona que resultan de un proceso secuencial de inserción y acoplamiento reductor C–N. En comparación con fenilacetamidas y benzamidas ciclopaladiadas, estas ciclaciones mediante acoplamientos C-N son más difíciles debido al mayor tamaño de los paladaciclos de partida, y sólo fueron satisfactorias a partir de los paladaciclos con la amida no sustituida; en los casos de los derivados con el grupo NHMe, los acoplamientos C-N están dificultados debido al impidimento estérico del grupo metilo y a la baja acidez del protón NH. Las reacciones de los complejos catiónicos C,O-ciclopaladiados con alquinos internos han permitido el aislamiento de paladaciclos de siete, ocho y nueve miembros, que resultan de la inserción de una molécula de alquino en el enlace Pd-C; los paladaciclos de nueve miembros son los primeros de ese tamaño obtenidos mediante monoinserciones de alquinos. Estas reacciones son más rápidas para anillos de mayor tamaño. Las reacciones de paladaciclos agrandados con CO pueden dar benzo[c]azepina-1,3-dionas 4,5-disustituidas, benzo[d]azocina-2,4(1H,3H)-dionas 5,6-disustituidas, o 1,2-dihidro-4H-benzo[e]azonina-3,5-dionas 6,7-disustituidas, que son el resultado de un proceso secuencial de inserción de CO y acoplamiento reductor C-N. Estas ciclaciones están generalmente más favorecidas para derivados con la función amida sin sustituyentes. Las reacciones de las benzamidas ciclopaladiadas que contienen metil o etil fenilpropiolato insertado (derivados de NHMe) con CO dan lugar a una adicción aza-Michael del fragmento NHMe al grupo vinilo tras la inserción de CO, conduciendo a la formación de derivados de isoindolin-1-ona. Las reacciones de los paladaciclos resultantes de monoinserciones de alquinos con isocianuros fueros intentadas solamente para los derivados de fenilacetamida. A diferencia de las reacciones análogas con CO, no se obtuvieron heterociclos de ocho miembros, sino una serie de derivados acíclicos de acrilamida o acrilonitrilo, cuya naturaleza depende de las condiciones de reacciones y del isocianuro.<br>OBJETIVES This thesis describes the synthesis and study of the reactivity toward unsaturated molecules of aryl palladium complexes containing an amide group in ortho position, with the main objective of exploring synthetic routes to new organic compounds, in particular, heterocyclic compounds. A series of aryl ligands with the amide function directly bonded to the aryl ring (ortho-palladated benzamides) or connected through one or two metylene groups (ortho-palladated phenylacetamides or 3-phenylpropanamides) are employed. This study has allowed the synthesis of a series of new palladacycles and heterocycles of different ring sizes (5, 6, 7, 8 or 9 members). METHODOLOGY A series of sequential steps have been followed for this study: (1) synthesis of the new aryl palladium complexes and C,O- and C,N-palladacyclic derivatives; (2) insertion of CO or isocyanides into the Pd-C bond and optimization of the reaction conditions to obtain heterocyclic products; (3) insertion of alkynes into the Pd-C bond of C,O-palladacycles and characterization of the resulting enlarged palladacycles; (4) insertion of CO or isocyanides into the Pd-C bond of the enlarged palladacycles to obtain heterocycles of a larger size. RESULTS A series of iodo(aryl)palladium(II) complexes have been synthesized by oxidative addition of 2 iodobenzamides, 2-iodophenylacetamides or 3 (2 iodophenyl)propanamides, to Pd(0) in the presence of a chelating N^N ligand. The reactions of these complexes with silver triflate lead to the abstraction of the iodide ligand and the formation of cationic five-, six-, or seven-membered C,O-palladacycles, in which the amide function is coordinated through the oxygen atom. On the other hand, neutral five-, six-, or seven-membered C,N-palladacyclic amidates have been obtained upon deprotonation of the amide function (NH2 or NHMe derivatives). The insertion of CO or isocyanides into the Pd–C bond of the ortho-palladated benzamides triggers the rapid C-N reductive coupling (NH2 or NHMe derivatives), leading to the formation of isoindoline-1,3-diones (phthalimides) or 3 iminoisoindolin-1-ones. These reactions involve the deprotonation of NH2 or NHMe groups. Intramolecular C-N and/or C-O reductive couplings can take place after the insertion of CO or XyNC into the Pd-C bond of ortho-palladated phenylacetamides, depending on the substituents on the amidic nitrogen, finally leading to isoquinoline- or isocoumarin-based heterocycles. The C-O couplings involve the deprotonation of the -CH2 group and are the first reported palladium-mediated C-O couplings involving an amide function. The reactions of cyclopalladated 3-phenylpropanamides with CO or XyNC have allowed the synthesis of seven-membered cyclic imides and one iminobenzazepinone resulting from insertion/C-N reductive coupling sequences. When compared to cyclopalladated phenylacetamides and benzamides, the cyclizations via C-N couplings proved to be more difficult because of the larger ring size of the starting palladacycles, and were only satisfactory from the palladacyclic derivatives with the unsubstituted amide; in the cases of the NHMe derivatives, the C-N couplings are hampered because of the steric hindrance of the methyl group and the lower acidity of the NH proton. The reactions of the cationic C,O-cyclopalladated complexes with internal alkynes have allowed the isolation of seven-, eight- and nine-membered palladacycles resulting from the insertion of the alkyne into the Pd–C bond; the nine-membered palladacycles are the first of that size obtained from alkyne monoinsertions. These insertions are faster for larger ring sizes. The reactions of the enlarged palladacycles with CO may give 4,5-disubstituted benzo[c]azepine-1,3-diones, 5,6-disubstituted benzo[d]azocine-2,4(1H,3H)-diones, or 6,7-disubstituted 1,2-dihydro-4H-benzo[e]azonine-3,5-diones, which are the result of CO insertion/C–N reductive coupling sequences. These cyclizations are generally more favored for derivatives with the unsubstituted amide function. The reactions of the benzamide palladacycles containing inserted methyl or ethyl phenylpropiolate (NHMe derivatives) with CO result in an aza Michael addition of the NHMe moiety to the vinyl group after the insertion of CO, leading to the formation of isoindolin-1-one derivatives. The reactions of palladacycles resulting from alkyne monoinsertions with isocyanides were tested only for the phenylacetamide derivatives. In contrast to the analogous reactions with CO, eight-membered heterocycles were not obtained, but a series of diverse acyclic acrylamide or acrylonitrile derivatives, whose nature depends on the reaction conditions and the isocyanide.

Breast cancer remains the leading cause of cancer death among women worldwide. This is in part due to late diagnosis, high recurrence rate and the development of drug resistance. Indeed, even though oestrogen receptor-positive breast cancers are known to respond to hormonal therapy, drug resistance is a common occurrence. Furthermore, triple negative breast cancers lack a specific therapeutic target, which has led to poor treatment outcomes. Hence, there is a critical need for new therapeutic approaches. Our laboratory previously identified a novel palladium-based compound, AJ-5, that exhibit potent anti-cancer activity in triple negative and oestrogen receptor-positive breast cancer cells. However, AJ-5 is poorly soluble, therefore, a series of water soluble AJ-5-based compounds were synthesized. The aim of this study was to test and characterise the anti-cancer activity of one of these AJ-5 analogues, BTC2, in triple negative (MDA-MB-231) and oestrogen receptor-positive (MCF7) breast cancer cell lines. Cytotoxicity assays were performed and BTC2 was shown to inhibit the proliferative rates of breast cancer cells with calculated IC50 values of 0.49μM in MCF7 cells and 0.58μM in MDA-MB-231 cells. BTC2 did not display considerable selectivity to breast cancer cells as the calculated IC50 value for the normal fibroblast cell line (FG0) was found to be 0.85μM and thus the selectivity index was less than 2 in both cell lines. Clonogenic assays were performed and BTC2 was shown to inhibit the long term (10 to 21 days) survival of MCF7 and MDA-MB-231 cells as it reduced their colony forming ability. Western blot analyses and immunofluorescence with an antibody to ƴH2AX, a robust marker of DNA double strand breaks, indicated that BTC2 acts by inducing DNA damage as the levels of this protein increased in drug treated cells. Light microscopy revealed that BTC2 induced morphological features of apoptosis (membrane blebbing and cell shrinkage) and autophagy (vacuoles reminiscent of autophagosomes). To further characterise the molecular mechanism underpinning the cytotoxic effects of BTC2, western blotting was performed with antibodies against key protein markers of stress signalling, cell cycle, apoptosis and autophagy. The results indicated that BTC2 activated the p38 MAP kinase signalling pathway and the p53 response in MCF7 cells. It is worth noting that MDA-MB-231 cells have a mutant p53 but that the p53 target protein, p21, was upregulated in both MCF7 and MDA-MB-231 cells. This suggests that p21 is regulated by a p53-independent mechanism in the MDA-MB-231 cells. BTC2 was shown to induce apoptosis and autophagy in both breast cancer cell lines as demonstrated by increased levels of cleaved PARP and LC3-II respectively. Apoptosis was confirmed by Annexin V-FITC/ propidium iodide double staining using flow cytometry. Taken together, data from this study suggest that BTC2 represents a promising anti-cancer drug for the treatment of triple negative and oestrogen receptor-positive breast cancer cells.

<p>This thesis deals with the design of ligands for efficientasymmetric catalysis and studies of the conformation of theligands in the catalytically active complexes. All ligandsdeveloped contain chiral oxazoline heterocycles.</p><p>The conformations of hydroxy- and methoxy-substitutedpyridinooxazolines and bis(oxazolines) during Pd-catalysedallylic alkylations were investigated using crystallography,2D-NMR techniques and DFT calculations. A stabilising OH-Pdinteraction was discovered which might explain the differencein reactivity between the hydroxy- and methoxy-containingligands. The conformational change in the ligands due to thisinteraction may explain the different selectivities observed inthe catalytic reaction.</p><p>Polymer-bound pyridinooxazolines and bis(oxazolines) weresynthesised and employed in Pd-catalysed allylic alkylationswith results similar to those of monomeric analogues;enantioselectivities up to 95% were obtained. One polymer-boundligand could be re-used several times after removal of Pd(0).The polymer-bound bis(oxazoline) was also used in Zn-catalysedDiels-Alder reactions, but the heterogenised catalyst gavelower selectivities than a monomeric analogue.</p><p>A series of chiral dendron-containing pyridinooxazolines andbis(oxazolines) were synthesised and evaluated in Pd-catalysedallylic alkylations. The dendrons did not seem to have anyinfluence on the selectivity and little influence on the yieldwhen introduced in the pyridinooxazoline ligands. In thebis(oxazoline) series lower generation dendrimers had a postiveon the selectivity, but the selectivity and the activitydecreased with increasing generation.</p><p>Crown ether-containing ligands were investigated inpalladium-catalysed alkylations. No evidence of a possibleinteraction between the metal in the crown ether and thenucleophile was discovered.</p><p>A new type of catalyst, an oxazoline-containing palladacyclewas found to be very active in oxidations of secondary alcoholsto the corresponding aldehydes or ketones. The reactions wereperformed with air as the re-oxidant. Therefore, this is anenviromentally friendly oxidation method.</p><p><b>Keywords:</b>asymmetric catalysis, chiral ligand,oxazolines, conformational study, allylic substitution,polymer-bound ligands, dendritic ligands, crown ether,oxidations, palladacycle.</p>

Dit wil voorkom asof metallasiekels ‘n betreklike nuwe generasie van kataliste is, wat nie volkome vir gebruik in die industrie bestudeer is nie. Meeste van die bekende metallasiekels is fosfor, en tot ‘n mindere mate, swael gebasseerde mono- en bidentate metallasiekels. Relatief min is bekend oor die ooreenkomstige stikstof gebasseerde metallasiekels. Die doelwit van hierdie studie was om vas te stel of metallasiekels van stikstof en swael ligande vergelykbaar is met metallasiekels van fosfor ligande en of enige van dié vergelyk kan word met die standaard palladium en fosfor kataliste wat gewoonlik in situ berei word. ‘n Paar probleme wat ondervind is met organometaal literatuur was, onderandere, ‘n gebrek aan volledige eksperimentele prosedures vir metallasiekel sintese asook ‘n tekort aan volledige karakteriseringsdata. Metallasiekelvorming behels die insersie van ‘n metal in ‘n geaktiveerde C-H binding. Organometaal literatuur beskou metallasiekel vorming as oksidatiewe addisie gevolg deur redutiewe eliminasie. Meganisties gesproke het hierdie terme nie veel betekenis nie. Dit is egter moontlik om die reaksie te rasionaliseer in terme van suur/basis interaksies asook elektrofiliese substitusie wat nie die metal se oksidasie toestand verander nie. Die kritiese afhanklikheid van palladasiekel vorming op die reaksiekondisies het duidelik geword gedurende die studie. Die vorming van metallasiekels van palladium is altyd in kompetisie met ander prosesse soos kompleksasie en reduksie van palladium(II). Direkte metallering met palladium asetaat was net suksesvol met fosfor ligande, terwyl palladium chloried weer net suksesvol met stikstof ligande was. Die asetaatioon speel ‘n baie belangrike rol, naamlik om as basis op te tree. Palladium chloried het nie sulke sterk basiese eienskappe nie en dus misluk palladasiekel vorming met fosfor ligande. Wanneer hierdie feite in ag geneem word, is dit duidelik hoekom dit so moeilik was om die swak beskryfde literatuur metodes te volg. Sommige metallasiekels kan nie deur direkte insersie berei word nie en moet dus deur oksidatiewe addisie van halogeen verbindings gevorm word. Kermerkende verskille tussen die KMR spektra van die metallasiekel en sy vry ligand maak dit moontlik om te onderskei tussen die vorming van eenvoudige komplese en die metallasiekel. FAB-MS karakterisering is ook ‘n goeie metode om die verloop van metallering to moniteer. Die bereide metallasiekels en die standaard Pd(OAc)2/PPh3 sisteem is met mekaar vergelyk as katalisatore in die Heck reaksie. Met ‘n ariel jodied as, toon die stikstof palladasiekels hoër aktiviteit as die fosfor palladasiekels, terwyl hul aktiviteit vergelykbaar is met die standaard nie-palladasiekel kataliste. Die pinser komplese het amper geen aktiviteit onder hierdie kondisies getoon nie. Wat die meganisme van die reaksie betref, is bewyse vir die omsetting van die palladasiekel na ‘n palladium(0) spesie al aangevoer, maar meeste outeurs verkies ‘n meganisme wat ‘n Pd(II)/Pd(IV) oksidatiewe verandering behels. Twee tipes reaksies wat van groot belang is vir Sasol is isomerisasie en hidroformilering/alkoksikarbonilering van alkene. Daar is gevind dat palladasiekels oneffektief is in die reaksies met koolstof monoksied, omdat hulle gereduseer word na palladium(0). Die moontlikheid dat hierdie verbindings kan optree as kataliste in hidrogenasie reaksies is dus onwaarskynlik. Palladasiekels hou tog belofte in as kataliste vir olefien isomerisasie. Wanneer die katalitiese eienskappe van metallasiekels bestudeer word, is dit duidelik dat metallasiekels ‘n verandering in oksidasie toestand ondergaan as deel van die katalitiese siklus. In gevalle waar ‘n Pd(II) na Pd(IV) oksidasietoestand verandering moet plaasvind, sal dit noodwendig ‘n baie hoë energie proses wees. Dit sal dan die lae tempo van kataliese verklaar. Dus is dit amper seker dat metallasiekels beperkte toepassing sal vind in die industrie. Die vermoë van metallasiekels om as kataliste op te tree in reaksies waar ‘n verandering in oksidasie toestand nie nodig is nie, is to dusver nog nie ondersoek nie.<br>Prof. C.W. Holzapfel

碩士<br>國立中興大學<br>化學系<br>93<br>Three pendant benzamidines [Ph-C(=NC6H5)-{NH(CH2)2NMe2}] (1), [Ph-C(=NC6H5)-{NH(CH2Py)}] (2) and [Ph-C(=NC6H5)-{NH(o-C6H4)(oxazoline)}] (3) are described. Reaction of 1, 2 or 3 with one molar equivalent of Pd(OAc)2 yields orthometallated complexes [Ph-C{-NH(1-C6H4)}{=N(CH2)2NMe2}]Pd(OAc) (4), [Ph-C{-NH(1-C6H4)}{=N (CH2Py)}]Pd(OAc) (5) and [Ph-C{-NH(1-C6H4)}{=N(o-C6H4)(oxazoline)}]Pd(OAc) (6), respectively. Treatment of 4, 5 or 6 with excess lithium chloride affords complexes [Ph-C{-NH(1-C6H4)}{=N(CH2)2NMe2}]PdCl (7), [Ph-C{-NH(1-C6H4)}{=N(CH2Py)}]PdCl (8) and [Ph-C{-NH(1-C6H4)}{=N(o-C6H4)(oxazoline)}]PdCl (9). The molecular structures of 1, 3, 5, 6 and 7 are determined by X-ray structure analysis. Plausible mechanism for the formation of those palladacycles is also proposed.

碩士<br>中興大學<br>化學系所<br>95<br>Treatment of three novel tridentate C,N,S-donor ligand precursors1-3 with palladium(II) salts afforded orthometallated palladium(II) complexes 4-9. Crystal structures are reported for complexs 5-8 and 5’. The application of these novel palladacyclic complexes as catalyses for the Suzuki and Heck reactions with aryl halide substrates was examined, affording coupled products in good to excellent yields.Of particular note, complex 6 showed high TON value up to 106 with 4-Bromoacetophenone in Suzuki reaction.

碩士<br>國立彰化師範大學<br>化學系<br>101<br>The preparation of a series of ligand precursors featuring imidazo[1,2-a]pyridine and amido functional groups is reported. The reactions between the new ligand precursors, pyridine, and palladium acetate in DMF afforded monodentate Pd(II) abnormal carbene complexes. An isomeric Pd(II) normal carbene complex with a formally identical steric environment to that of the abnormal carbene counterpart was also prepared. The isomeric pairs were characterized by X-ray structural studies. Under a different complexation condition of employing PdCl¬2 as metal precursor, a CC-type palladacycle formed by the C–H activation at the ortho-N-phenyl and methylene carbons was obtained. The use of a similar ligand precursor with a NH instead of NMe group produced a palladalactam complex. In contrast to the previous work in the literature, due to the rigidity of the fused heterocyclic ring, the palladalactam complex did not undergo intramolecular proton transfer via the coordinated N atom. Overall, we demonstrated that proper modification of the structures of ligand precursors and complexation conditions allowed us to obtain a full range of intriguing Pd(II) complexes including abnormal and normal carbene complexes, palladalactam, and CC-type palladacycles via A–H bond (A = N, C) activations.

碩士<br>國立中山大學<br>化學系研究所<br>98<br>An effiecient stoichiometric amount system has been developed for the synthesis of N-phenylpyridin-2-amine Palladacycle, and then reation with aryl trifluoroborate to 9-(pyridine-2-yl)-9H-carbazoles by C-H bond activation/ C-C bond formation and C-N bond formation. The subsitutent effect of the aryl trifluoroborate with N-phenylpyridin-2-amine Palladacycle intermediate was observed. Mechanistic studies of C-H bond cleavaged, including trapping of reaction intermediates and kinetic isotope effect experiments, are also presented.

博士<br>國立中興大學<br>化學系所<br>96<br>The thesis discusses some palladacycles and magnesium complexes applied in catalytic reactions. For convenience and better understanding, the thesis is divided into two parts. The first part describes palladium-catalyzed reactions and the second part deals with ROP reaction catalyzed with magnesium complexes. Part one-A： Preparation of novel unsymmetrical, tridentate sulfur-containing ligand precursors, PhN=C(CMe2)(NPh)C=N(CH2)2SR [R=CMe3, Ph] are described. Reaction of ligand precursors with one molar equivalent of Pd(OAc)2 yields palladium(II) complexes, [PhN=C(CMe2)(N-η1-Ph)C=N(CH2)2SR]Pd(OAc). Treatment of orthometallated palladium(II) acetate complexes with excess of LiCl in methanol gives the complexes [PhN=C(CMe2)(N-η1-Ph)C=N(CH2)2SR]PdCl. Molecular structures have been determined by X-ray diffraction. The application of those novel palladacyclic complexes to the Suzuki and Heck reactions with aryl halide substrates was examined. Part one-B： Four new ligand precursors, PhN=C(CMe2)(NPh)C=N(E) [E =(CH2)2OMe, CH2C(=O)OMe, (CH2)2CH3, and C6H5] are reported. Treatment of ligand precursors with one molar equivalent Pd(OAc)2 in THF or CH3CN affords aceto-bridged palladium(II) complexes, [{PhN=C(CMe2)(N-η1-Ph)C=N(E)}Pd(OAc)]2, as di-nuclear palladium complexes. Reactions of Palladium(II) complexes with excess saturated NaCl(aq) in acetone afford orthometallated dimer or monomer palladium(II) complexes, as [{PhN=C(CMe2)(N-η1-Ph)C=N(CH2)2CH3}PdCl]2 or [PhN=C(CMe2)(N-η1-Ph)C=N(E)]PdCl. The crystal and molecular structures are reported and the catalytic activities of these palladacycles toward the Suzuki and Heck reactions are investigated. Part two： A new series of mononuclear magnesium complexes of type L2Mg (where L = anilido-oxazolinate ligands bearing different functional groups) has been prepared. The activities of magnesium complexes toward the ring opening polymerization of L-lactide have been investigated. Experimental results show that L2Mg complexes efficiently initiate the ring-opening polymerization of L-Lactide in the presence of benzyl alcohol and yielding polymers in a controlled fashion.