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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / New compounds phenylphosphinates and diphenylphosphinates silver (I) were synthe-sized and characterized with two coordination polymers and five molecular coordination complexes. The phosphinates are in oxygen-metal strong interactions due to the polarity of the P-O bond, and thus, they become good ligands in the formation of polymer chains in the solid state with a large number of monovalent metal centers Ag(I). Two precusores polymer were synthesized in order to study the properties of the metal center with phosphinic ligands: catena-poly[silver(I)-μ-diphenylphosphinate], 1 and phyllo-poly[silver(I)-μ-phenylphosphinate] 2, the from their metal complexes were formed aqua-κO-difenilfosfinato-κO-bis(triphenylphosphine-κP)silver(I) 3·H2O, 3·½ H2O·½C3H6O, aqua-κO-phenyilphosphinate-κO-bis(triphenylphosphine-κP)silver(I), 4, isopropanol-κO diphe-nylphosphinate-κO-bis(triphenylphosphine-κP)silver(I), 5, and di-μ-chloro-2:3κ2Cl-diphenylphosphinate-1κ2O,O'-tris{μ-bis(diphenylphosphine)etane}-1:2κP,P';1:3κP,P';2:3κP,P'-trisilver(I), 6. All compounds have the metal center silver(I) with distorted tetrahedral geometry at the packaging structure which might also reduce some bond lengths and angles. The compounds were characterized by various analytical techniques whenever possible the amount of sample available. Among them: melting point, elemental analysis of carbon and hydrogen, IR spec-troscopy, scanning electron microscopy, thermogravimetric analysis, X-ray diffraction single-crystal and X-ray diffraction powder. / Novos compostos de fenilfosfinatos e difenilfosfinatos de prata(I) foram sintetizados e caracterizados, sendo dois polímeros de coordenação e cinco complexos de coordenação mo-leculares. Os fosfinatos constituem-se em fortes interações metal oxigênio devido à polarida-de da ligação P O. Sendo assim, tornam-se bons ligantes na formação de cadeias poliméricas no estado sólido com um grande número de centros metálicos monovalentes Ag(I). Dois precusores poliméricos foram sintetizados afim de estudar as propriedade do cen-tro metálico com ligantes fosfínicos: catena-poli[prata(I)-μ-difenilfosfinato], (1) e phyllo-poli[prata(I)-μ-fenilfosfinato], (2). A partir deles cinco complexos metálicos foram formados, sendo eles: aqua-κO-difenilfosfinato-κO-bis(trifenilfosfina-κP)prata(I), (3·H2O) e (3·½H2O·½C3H6O), aqua-κO-fenilfosfinato-κO-bis(trifenilfosfino-κP)prata(I), (4), isopropa-nol-κO-difenilfosfinato-κO-bis(trifenilfosfina-κP)prata(I), (5) e di-μ-cloro-2:3κ2Cl-difenilfosfinato-1κ2O,O'-tris{μ-bis(difenilfosfino)etano}-1:2κP,P';1:3κP,P';2:3κP,P'-triprata(I), (6). Todos os compostos tem o centro metálico prata(I) com geometria tetrádrica distorcida, pelo empacotamento da estrutura cristalina que força também a redução de alguns compri-mentos de ligação e ângulos. Os compostos foram caracterizados por várias técnicas analíticas sempre que possível pela quantidade de amostras disponível. Dentre elas: ponto de fusão, aná-lise elementar de carbono e hidrogênio, espectroscopia de IV, microscopia de varredura ele-trônica, análise termogravimétrica, difração de raios X de monocristal e difração de raios X em pó.

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Gold catalysis has become an important tool to achieve highly chemoselective p-acid activation. Exceptional reactivity and selectivity are often encountered under mild reaction conditions. These properties have made gold(I) complexes suitable catalysts for tremendous applications in the total synthesis of natural products. The first chapter will highlight a number of total syntheses using gold catalysis as a key step. The second chapter will cover our application of the gold(I)-catalyzed 6-endo-dig carbocyclization for the synthesis of bridgehead-substituted scaffolds and its use toward the synthesis of PPAP natural products. This research has opened our eyes to the utility of biphenylphosphine ligands, particularly JohnPhos, in gold(I)-catalysis. The reactivity and selectivity exhibited by gold(I) complexes is modulated by the nature of the ancillary ligand. Recent research rationalizes the impact of these ligands on the divergent reactivity observed between cationic and carbenoid intermediates. Our desire to favor the 6-endo-dig pathway has led us toward the discovery of another example of the diagonal reactivity that NHC carbene and biphenylphosphine ligands can bring to gold(I)-catalysis. Chapter three will explain the development of a selective gold-catalyzed synthesis of fused carbocycles . Our selective divergent synthesis of fused carbocycles, combined with the Diels–Alder reaction, has brought new synthetic opportunities. Chapter four will describe our approach toward the synthesis of various polycyclic diterpene-related frameworks. Starting with a unique linear precursor, we have developed a new “one-pot” process for the synthesis of three different polycyclic compounds related to the terpenoid family. The facile modulation of the linear precursor and the use of different dienophiles during the Diels–Alder reaction could enable the synthesis of diverse polycyclic analogues based on three principal frameworks. The gold(I)-catalyzed synthesis of fused carbocycles reached some limitations during our study. Regioselective control was found to be substantially more challenging, with terminal alkynes or alkynes bearing a sterically and electronically neutral methyl substituent. In chapter five, we will discuss how the complementarity of silver(I) catalysis to gold(I) catalysis enabled the selective divergent synthesis of three different fused carbocycles from a unique precursor. Moreover, copper(I) catalysis has given access to the 6-endo-dig pathway on terminal alkynes without the formation of a vinylidene intermediate.

Gold catalysis has become an important tool to achieve highly chemoselective p-acid activation. Exceptional reactivity and selectivity are often encountered under mild reaction conditions. These properties have made gold(I) complexes suitable catalysts for tremendous applications in the total synthesis of natural products. The first chapter will highlight a number of total syntheses using gold catalysis as a key step. The second chapter will cover our application of the gold(I)-catalyzed 6-endo-dig carbocyclization for the synthesis of bridgehead-substituted scaffolds and its use toward the synthesis of PPAP natural products. This research has opened our eyes to the utility of biphenylphosphine ligands, particularly JohnPhos, in gold(I)-catalysis. The reactivity and selectivity exhibited by gold(I) complexes is modulated by the nature of the ancillary ligand. Recent research rationalizes the impact of these ligands on the divergent reactivity observed between cationic and carbenoid intermediates. Our desire to favor the 6-endo-dig pathway has led us toward the discovery of another example of the diagonal reactivity that NHC carbene and biphenylphosphine ligands can bring to gold(I)-catalysis. Chapter three will explain the development of a selective gold-catalyzed synthesis of fused carbocycles . Our selective divergent synthesis of fused carbocycles, combined with the Diels–Alder reaction, has brought new synthetic opportunities. Chapter four will describe our approach toward the synthesis of various polycyclic diterpene-related frameworks. Starting with a unique linear precursor, we have developed a new “one-pot” process for the synthesis of three different polycyclic compounds related to the terpenoid family. The facile modulation of the linear precursor and the use of different dienophiles during the Diels–Alder reaction could enable the synthesis of diverse polycyclic analogues based on three principal frameworks. The gold(I)-catalyzed synthesis of fused carbocycles reached some limitations during our study. Regioselective control was found to be substantially more challenging, with terminal alkynes or alkynes bearing a sterically and electronically neutral methyl substituent. In chapter five, we will discuss how the complementarity of silver(I) catalysis to gold(I) catalysis enabled the selective divergent synthesis of three different fused carbocycles from a unique precursor. Moreover, copper(I) catalysis has given access to the 6-endo-dig pathway on terminal alkynes without the formation of a vinylidene intermediate.

This work focuses on the design and synthesis of Au(I) and Ag(I) complexes from ligand systems that aim to combine both N-heterocyclic carbene (NHC) and phosphine ligand types. A number of synthetic approaches towards both the ligands and the prepared metal complexes have been developed, with a concerted effort on achieving the desired Au(I) or Ag(I) complexes with minimal reaction steps and synthetic style. The thesis body is divided into two main sections. The first section addresses the preparation of suitable ligand precursors of potential Au(I) and Ag(I) complexes in the form of halo- and phosphino-functionalised imidazolium salts. Several series of haloalkylimidazolium salts were prepared that encompass a range of halogens (Cl, Br, I), alkyl substituents (Me, i-Pr, t-Bu, n-Bu), differing alkyl linker length (n = 0-3), and a variety of organic spacers employed to bridge multi-imidazolium moieties. Novel bidentate and multidentate phosphinoalkylimidazolium salts were synthesised from the various haloalkylimidazolium salts, via the substitution of a halide with nucleophilic diphenylphosphide. A new approach towards rare methylene bridged phosphinomethylimidazolium salts was achieved from the reactions of halomethylimidazolium salts with diphenylphosphine. The second section investigates the preparation of Au(I) and Ag(I) complexes from the halo- and phosphino-functionalised imidazolium salts. A series of dicationic 10, 12, and 14-membered metallacyclic Ag(I) complexes were prepared from the bidentate phosphinoalkylimidazolium salts. The dinuclear Ag(I) metallacycles combine two phosphino-functionalised NHC ligands that are bridged by two coordinated Ag(I) ions in an exclusively head-to-head arrangement. A dinuclear Ag(I) metallacycle was investigated for transmetallation potential to a Au(I) complex and found to selectively transmetallate at the Ag(I) coordinated to the NHC ligands to form a bimetallic metallacycle. Unexpected phosphine oxidation of a 10-membered dinuclear Ag(I) metallacycle resulted in complex disproportionation to an isolable and rare silver(I) trimer. Metal-NHC complexes from haloalkylimidazolium salts have not been reported previously, a novel approach to the synthesis of a series of Au(I) complexes from haloalkylimidazolium salts and a respective gold source was developed and is reported herein. Different synthetic approaches towards Au(I) complexes with the phosphinoalkylimidazolium salts explored a variety of ways to generate the NHC from an imidazolium in the presence of the phosphine. A one-pot, high yielding synthesis of a dinuclear Au(I) complex from PPh3 was also devised, with controlled assembly of the complex resulting in a similar head-to-head ligand arrangement to the dinuclear Ag(I) metallacycles. As an aside, a family of mononuclear [Au(R2NHC)2]+ complexes (R = Me, i-Pr, t- Bu, n-Bu, Cy) prepared previously in our research group, was expanded because of the promising antimitochondrial activity shown by [Au(i-Pr2NHC)2]+. Two new [Au(R2NHC)2]+ complexes with simple alkyl chain functionality were prepared with fine-tuned lipophilicity in close proximity to that of [Au(i-Pr2NHC)2]+.

Polycyclic nitrogen containing heterocycles form the basic skeleton of numerous alkaloids and physiologically active drugs. Alloyohimbane was obtained from 3,4-dihydro-â-carboline using an iron-mediated [2+2+1] cycloaddition as the key-step. The bis-TMS-diyne was conveniently obtained by the C-alkylation of 3,4-dihydro-â-carboline followed by N-alkylation. Demetalation of the iron-complex followed by hydrogenation, E-ring expansion, and reduction provided alloyohimbane, a structurally and biologically interesting substance, via a linear eight-step sequence in 7% overall yield based on 3,4-dihydro-â-carboline. Another sequence provided (±)-alloyohimbane and (±)-3-epi-alloyohimbane in nine steps. The pyrrole unit occurs in a variety of naturally occurring compounds, pharmaceutical products and polymers. A novel two-step procedure for the synthesis of pyrroles by addition of a propargyl Grignard reagent to a Schiff base and subsequent silver(I)-promoted oxidative cyclization of the resulting homopropargylamine has been developed. The generality of this reaction was proven by the synthesis of a broad variety of substituted pyrroles using silver(I)-promoted cyclization. A three-step synthesis of (±)-harmicine, a natural product isolated from the Malaysian plant Kopsia griffithii having strong anti-leishmania activity, from 3,4-dihydro-â-carboline is achieved by addition of 3-trimethylsilylpropargyl Grignard reagent, Ag(I)-promoted oxidative cyclization to a pyrrole, and chemoselective hydrogenation of pyrrole ring. Total synthesis of anti-tumor active crispine A and biologically active 1,2,3,5,6,10b-hexahydropyrrolo[2,1-a]isoquinoline have been achieved in three steps using silver(I)-promoted oxidative cyclization as key step.

Silver(I) complexes of type LnAgX (X = organic ligand, such as carboxylates, dicarboxylates, Schiff-base; L = Lewis-bases, e. g. PnBu3, P(OMe)3, P(OEt)3; n = 1, 2, 3) have been synthesized and characterized with respect to their suitability for the Chemical Vapour Deposition (CVD) of silver thin films. For some of these compounds single crystal could be obtained. Their solid-state structure was determined by single crystal X-ray diffraction. The volatility, thermal stability, and gas phase decomposition mechanism of selected compounds were studied using temperature-programmed and in-situ mass spectrometry. CVD experiments were performed according to the results of the gas phase analysis. Silver films could be grown by using a cold-wall CVD reactor. The morphology of the latter films was determined. / Silber(I) Komplexe LnAgX (X = organische Ligand, Z. B. Carboxylate, Dicarboxylate, Schiff Base; L = Lewis-Base, Z. B. PnBu3, P(OMe)3, P(OEt)3; n = 1, 2, 3) wurden Bezug auf ihre Eignung für die chemische Gasphasenabscheidung von Silberfilmen synthetisiert und charakterisiert. Von einigen dieser Verbindung konnten Einkristalle erhalten werden. Der Bau dieser Verbindungen wurde mittels Röntgeneinkristallographie ermittelt. Ausgewählten Verbindungen wurden mit Temperatur-programmierter und in-situ Massenspektrometrie analysiert. Gasphasenabscheidungs- mechanismen für einige Prekursoren sind vorgestellt. CVD-Abscheidungsexperimente wurden entsprechend den Ergebnissen der Gasphaseanalyse durchgeführt. Silber Schichten konnten mit einen Kaltwand CVD-Reaktor erzeugt werden, deren Oberflächenmorphologie wurde untersucht.

Polycyclic nitrogen containing heterocycles form the basic skeleton of numerous alkaloids and physiologically active drugs. Alloyohimbane was obtained from 3,4-dihydro-â-carboline using an iron-mediated [2+2+1] cycloaddition as the key-step. The bis-TMS-diyne was conveniently obtained by the C-alkylation of 3,4-dihydro-â-carboline followed by N-alkylation. Demetalation of the iron-complex followed by hydrogenation, E-ring expansion, and reduction provided alloyohimbane, a structurally and biologically interesting substance, via a linear eight-step sequence in 7% overall yield based on 3,4-dihydro-â-carboline. Another sequence provided (±)-alloyohimbane and (±)-3-epi-alloyohimbane in nine steps. The pyrrole unit occurs in a variety of naturally occurring compounds, pharmaceutical products and polymers. A novel two-step procedure for the synthesis of pyrroles by addition of a propargyl Grignard reagent to a Schiff base and subsequent silver(I)-promoted oxidative cyclization of the resulting homopropargylamine has been developed. The generality of this reaction was proven by the synthesis of a broad variety of substituted pyrroles using silver(I)-promoted cyclization. A three-step synthesis of (±)-harmicine, a natural product isolated from the Malaysian plant Kopsia griffithii having strong anti-leishmania activity, from 3,4-dihydro-â-carboline is achieved by addition of 3-trimethylsilylpropargyl Grignard reagent, Ag(I)-promoted oxidative cyclization to a pyrrole, and chemoselective hydrogenation of pyrrole ring. Total synthesis of anti-tumor active crispine A and biologically active 1,2,3,5,6,10b-hexahydropyrrolo[2,1-a]isoquinoline have been achieved in three steps using silver(I)-promoted oxidative cyclization as key step.

Silver(I) complexes of type LnAgX (X = organic ligand, such as carboxylates, dicarboxylates, Schiff-base; L = Lewis-bases, e. g. PnBu3, P(OMe)3, P(OEt)3; n = 1, 2, 3) have been synthesized and characterized with respect to their suitability for the Chemical Vapour Deposition (CVD) of silver thin films. For some of these compounds single crystal could be obtained. Their solid-state structure was determined by single crystal X-ray diffraction. The volatility, thermal stability, and gas phase decomposition mechanism of selected compounds were studied using temperature-programmed and in-situ mass spectrometry. CVD experiments were performed according to the results of the gas phase analysis. Silver films could be grown by using a cold-wall CVD reactor. The morphology of the latter films was determined. / Silber(I) Komplexe LnAgX (X = organische Ligand, Z. B. Carboxylate, Dicarboxylate, Schiff Base; L = Lewis-Base, Z. B. PnBu3, P(OMe)3, P(OEt)3; n = 1, 2, 3) wurden Bezug auf ihre Eignung für die chemische Gasphasenabscheidung von Silberfilmen synthetisiert und charakterisiert. Von einigen dieser Verbindung konnten Einkristalle erhalten werden. Der Bau dieser Verbindungen wurde mittels Röntgeneinkristallographie ermittelt. Ausgewählten Verbindungen wurden mit Temperatur-programmierter und in-situ Massenspektrometrie analysiert. Gasphasenabscheidungs- mechanismen für einige Prekursoren sind vorgestellt. CVD-Abscheidungsexperimente wurden entsprechend den Ergebnissen der Gasphaseanalyse durchgeführt. Silber Schichten konnten mit einen Kaltwand CVD-Reaktor erzeugt werden, deren Oberflächenmorphologie wurde untersucht.