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1
Unsworth, W. P. "Rhodium(II) catalysed Oxyamination Reactions." Thesis, University of Oxford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.526154.
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Mokrini, Hassan. "Activation et fonctionnalisation d'hydrocarbures saturés et aromatiques catalysés par des complexes du rhodium." Lille 1, 1990. http://www.theses.fr/1990LIL10069.
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Certains alcanes peuvent être fonctionnalisés catalytiquement par le biais du complexe rhcll2 (l=diphosphine chelatée), réduit électrochimiquement à -2v/ag en milieu benzonitrile sans sel de fond, sur cathode de platine, en présence d'une anode d'étain, d'aluminium ou de zinc. Nous avons noté des résultats tout à fait remarquables en terme de conversion de l'alcane et du rendement faradique à la suite d'une réaction d'oxydo-réduction se produisant entre l'anode de zinc et le précurseur catalytique rhcll2, sans qu'il soit nécessaire d'imposer de potentiel de réduction à la solution. Le système ainsi obtenu rhcll2/zn/ccl4 est plus actif que le système électrochimique et montre une sélectivité comparable à celle observée avec les initiateurs chimiques, et un effet isotopique très important. La réaction de transfert d'un cl de ccl4 vers l'alcane s'effectue selon un processus radicalaire. Ce dernier est initié par l'entité rhl2o obtenue à partir de rhcll2 par réduction cathodique, ou chimiquement par la poudre de zinc. Les expériences ont montré que l'espèce rhl2o activait préférentiellement la liaison c-cl par rapport a la liaison c-h. Les aromatiques sont aussi dimérisés catalytiquement par ce même système chimique. Les produits ainsi obtenus sont des dimères ar-ar. Le système rhcll2/zncf3cooh a permis également la dimérisation catalytique de l'éthylbenzène en o. Odiéthyl 1. 1biphényle (nombre de rotation: 4,8), résultat qui a pu être nettement amélioré en présence de ccl4 (nombre de rotation: 47)
3
Pascu, Sofia I. "Nickel (II), palladium (II), platinum (II) and rhodium (I) complexes of iminophosphine ligands." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270258.
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Sie, Eric-Robert Hian Bing. "Rhodium (II) catalysed reactions of α-diazo phosponates." Thesis, Loughborough University, 1992. https://dspace.lboro.ac.uk/2134/26017.
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The syntheses and reactions of some α-diazo phosphonates are reviewed. The work presented is based on the inter- and intra-molecular reactions of the previously proposed, transient rhodium carbenoid species with nucleophiles. In order to shed some light on the mechanism of the rhodium (11) catalysed insertion reactions of diazo compounds with nucleophiles and consequently to verify the presence of the rhodium carbenoid species or not, studies have been carried out to determine what factors affect the rate of insertion. Thus, the intermolecular rhodium (11) catalysed insertion reactions of a series of diazo compounds in the presence of various alcohols have been investigated. Some novel diazo compounds have been prepared and more efficient, more amenable routes to some known diazo compounds have been developed. It was found that rhodium (11) trifluoroacetamide is a significantly more active catalyst than rhodium (11) acetate, under the test conditions. Two new methods leading to the formation of functionalised cyclic ethers (five-, sixand seven-membered rings) have been developed. Both involve the insertion of an alcohol into an a-diazo phosphonate catalysed by rhodium (11) acetate as the initial step but whereas one method proceeds via an intermolecular Wadsworth-Emmons reaction, the other proceeds via the intramolecular variant of the same reaction. 7/6- and 717-Fused bicyclic ethers have been prepared from 3-oxooxepane 2- phosphonates via the Wadsworth-Emmons reaction. The oxepanes themselves were prepared in good yields by an intramolecular rhodium (11) catalysed O-H insertion reaction of a parent diazo alcohol. The same bicyclic systems could also be accessed by two different routes starting with t-butyl-7-hexyl-3-oxooxepane-2- carboxylate. Various novel synthetic routes leading to the formation of functionalised bicyclic, tricyclic and tetracyclic systems have been investigated. All involve the intramolecular rhodium (11) catalysed O-H insertion reaction of a diazo alcohol as a key cyclisation step.
5
Joyce, Lauren Elizabeth. "Ru(II), Os(II), and Rh2(II,II) Complexes as Potential Photodynamic Therapy Agents." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1291176129.
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Selden, Deborah Anne. "New rhodium(II) catalysts and enantioselective carbonyl ylide cycloadditions." Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418476.
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Beavis, Peter William. "Rhodium(II)-catalysed aziridination of homoallyl- and allyl-carbamates." Thesis, University of Nottingham, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442291.
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Adero, Philip O. "Heterocycle Synthesis via Rhodium (II)-Catalyzed Azido Carbenoid Cyclization." Youngstown State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1348595887.
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Grohmann, Markus. "Zweikernige Ruthenium(I,I)- und Rhodium(II,II)-Komplexe als Katalysatoren für Lactam-Synthesen durch intramolekulare carbenoide C-H-Insertion von alpha-Diazoacetamiden." [S.l. : s.n.], 2006. http://nbn-resolving.de/urn:nbn:de:bsz:289-vts-58707.
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Bellot, Morgane. "Caractérisation des dimères de récepteurs à l'angiotensine II AT1 et a2C-adrénergiques et conséquences fonctionnelles." Toulouse 3, 2013. http://thesesups.ups-tlse.fr/2185/.
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Les mécanismes de sécrétion de noradrénaline (NA) via les récepteurs de l'angiotensine (AT1) et alpha2-adrénergiques (alpha2A/C-AR) restant méconnus, nous avons émis l'hypothèse de l'implication d'un dimère AT1/alpha2C. Nos résultats montrent que ces deux récepteurs interagissent directement et que la liaison l'angiotensine II (AngII) et de NA stabilisent des conformations différentes du dimère. De plus, dans des conditions mimant l'hypertension artérielle (HTA ; costimulation NA+AngII), le dimère adopte une nouvelle conformation. En utilisant une technique originale permettant de mesurer spécifiquement l'activation des voies de signalisation intracellulaires induite uniquement par le dimère AT1/alpha2C, nous avons mis en évidence que la costimulation induit l'activation par le dimère d'une nouvelle voie de signalisation faisant intervenir la voie Galphas/PKA. Enfin, nous avons étudié la relevance physiologique de cette nouvelle entité in vivo en explorant l'activité du SNA chez la souris par microneurographie. De façon étonnante, la co-injection AngII+NA engendre une augmentation de l'activité du SNS, par rapport à l'injection d'AngII seule suggérant potentiellement un rôle du dimère AT1/alpha2C dans le contrôle de l'activité du SNA. En conclusion, l'ensemble de ces travaux montrent pour la première fois l'existence du dimère AT1/alpha2C et surtout la création d'une nouvelle entité pharmacologique via un dimère. A plus long terme, le dimère AT1/alpha2C pourrait représenter une nouvelle entité pharmacologique qui modulerait de façon originale le tonus sympathique et pourrait constituer une nouvelle cible de médicaments notamment dans le cadre du traitement de l'HTAMechanisms of norepinephrine (NE) secretion via angiotensin (AT1) and alpha2-adrenergic (alpha2A/C-AR) receptors remains unknown. So we hypothesized the involvement of a AT1/alpha2C dimer. Our results show that these two receptors are able to interact directly and binding of angiotensin II (Ang II) or NA stabilize different conformations of the dimer. In addition, under conditions mimicking arterial hypertension (HTN; costimulation NA+AngII), AT1/alpha2C dimer adopts a new conformation. Using a new technique allowing a specific measure of intracellular signaling pathways activation only induced by AT1/alpha2C dimer, we demonstrated that costimulation induces a new signaling pathway involving the Galphas / PKA pathway. Finally, we studied the physiological relevance of this new entity in vivo by exploring the SNS activity in mice by microneurography. Surprisingly, co-injection AngII + NA causes an increased SNS activity, compared to the injection of AngII alone, suggesting a role of AT1/alpha2C dimer in the control of controlling SNS activity. In conclusion, all this work show for the first time the existence of the AT1/alpha2C dimer and especially the creation of a new pharmacological entity in HTN condition. In the longer term, AT1/alpha2C dimer may represent a new pharmacological entity that originally modulate the sympathetic tone and may be a new drug target in particular the treatment of HTN
11
Gronow, Martin. "Separation of rhodium(III) from copper(II) in acidic chloride media." Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303893.
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La, PenseÌe Annemarie Agnes. "Homoleptic diarsine and diphosphine complexes of iron(II), ruthenium(II) and rhodium(III) : synthesis and electrochemistry." Thesis, University of Liverpool, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250371.
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Thu, Hung-yat, and 杜鴻溢. "Catalytic C-H bond functionalization reactions catalyzed by rhodium(III) porphyrin, palladium(II) and platinum(II) acetatecomplexes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B38798268.
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Pierson, Nicolas. "New chiral rhodium(II) catalysts for asymmetric synthesis with #apha#-diazocarbonyl substrates." Thesis, Queen's University Belfast, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263509.
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ALJOUBBEH, MALAK. "Etudes physico-chimiques de complexes binucleaires de rhodium(ii) et d'anthraceno-cryptates." Université Louis Pasteur (Strasbourg) (1971-2008), 1990. http://www.theses.fr/1990STR13079.
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Ce memoire presente principalement des etudes physico-chimiques qui permettent de proposer des mecanismes de coordination avec des ligands nouveaux. Le premier volet de ce travail concerne l'approche physico-chimique du mecanisme de catalyse stereoselective induite par des tetracarboxylates de dirhodium(ii). Pour cela, les proprietes thermodynamiques et cinetiques de la coordination de la pyridine par des complexes tetracarboxylates de dirhrodium(ii) encombres ont ete etudiees. Notre travail ainsi que l'etude structurale, ont permis de definir un encombrement optimal pour favoriser la stabilite des produits formes avec la pyridine, pris comme modeles de catalyseurs, et une accessibilite controlee du substrat. Le deuxieme volet s'interesse au comportement physico-chimique de deux anthraceno-cryptands que leurs proprietes complexantes et spectroscopiques designent comme des ligands particulierement interessants en chimie analytique. Ce travail a permis de montrer que les anthraceno-cryptands restaient des ligands forts de cations comme le thallium(i) et l'argent(i) dans le methanol et offraient d'excellentes possibilites de detection spectrophotometrique dans le visible. L'etude cinetique de la protonation des ligands a22 et a33 et de la dissociation en milieu acide de leurs complexes formes avec le thallium(i) et l'argent(i) a mis en lumiere un comportement tres differencie du cryptand a22, particulierement dans les mecanismes de protonation
16
Thu, Hung-yat. "Catalytic C-H bond functionalization reactions catalyzed by rhodium(III) porphyrin, palladium(II) and platinum(II) acetate complexes." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B38027872.
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Southby, Duncan P. W. "Rhodium(II) catalysed aziridinations of homoallylic garbamates: towards a synthesis of sphingofungin F." Thesis, University of Nottingham, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604313.
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This thesis details an expansion of substrate scope in the intramolecular aziridination reactions of homoallylic carbamates so as to generate aziridine products containing nitrogen bearing quaternary stereocentres. The use of this methodology towards a synthesis of sphingofungin F is detailed. The Introduction identifies the reactions of nitrenoids as key methods for the installation of nitrogen bearing quaternary stereo centres and reviews the current methodologies used in the CH-insertion and aziridination reactions of nitrenoids. The involvement of the Hayes group within the field is detailed and the research aims of the project are outlined, namely the effect that an allylic stereo centre and trisubstituted alkene will have upon the reaction of a series of homoallylic carbamates under the conditions developed previously within the group. Results and Discussion details the synthesis and aziridination of a range of trisubstituted homoallylic carbamates containing an allylic stereo centre to give the product aziridines in generally high yields and as single diastereoisomers. The utility of the aziridines as synthetic intermediates is demonstrated via the preparation of a small selection of functionalised derivatives and the use of similar aziridines in a synthesis of sphingofungin F is envisaged. Introduction to the Sphingofungins details the sh'ucture and isolation of the sphingofungins and their role as inhibitors of the serine palmitoyltransferase enzyme. Some of the more recent approaches to the sphingofungins are also reviewed. 11 Towards Sphingojimgin F details our attempts towards a synthesis of sphingofungin F using the diastereoselective aziridination reaction to install the key nitrogen bearing quaternary stereocentre. Further synthetic transfonnations gave access to a protected forn1 of the polar head of sphingofungin F. A summary of this work and the future steps required to complete the synthesis of sphingofungin F are presented. The thesis concludes with the Experimental section which gIves experimental procedures and full characterisation data for all novel compounds prepared herein.
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Zhou, Congying. "Ruthenium porphyrins and dirhodium (II, II) carboxylates catalyzed ylide-mediated cycloadditions and carbenoid transfer reactions." Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B31046484.
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Zhou, Congying, and 周聰穎. "Ruthenium porphyrins and dirhodium (II, II) carboxylates catalyzed ylide-mediated cycloadditions and carbenoid transfer reactions." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31046484.
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Yan, Kun. "Proteomic and biochemical studies of cytotoxic gold(I), silver(I) and rhodium(II) complexes." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B3963436X.
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Yan, Kun, and 嚴琨. "Proteomic and biochemical studies of cytotoxic gold(I), silver(I) and rhodium(II) complexes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B3963436X.
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Lin, Wing-shan, and 林穎珊. "Synthesis and biological studies of anti-cancer rhodium(II, II) carboxylates, anti-inflammatory silver(I) thiourea and microbially fabricated silver nanoparticles." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206649.
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Discovery of cisplatin as an effective anticancer agent has stimulated the development of metal based medicine. The recent advances in research on platinum, ruthenium and gold complexes have received much attention in medicinal chemistry, and studies of other less explored metal complexes may reveal alternative mode of mechanism as novel therapeutic agents. A series of dirhodium(II,II) complexes with carboxylate and carboxamidate ligands and thiourea complexes of coinage metals have been prepared in this study. Their biological activities and mechanisms of action have been studied.
Dirhodium(II,II) carboxylate complexes with variations of alkyl and benzoyl side chains were synthesized and displayed remarkable cytotoxicities to cancer cells with potency down to submicromolar level. The cytotoxicities of rhodium complexes were found to significantly correlate with the cellular uptake of the rhodium complexes. As revealed by oligonucleotide microarray and bioinformatic analysis, the mode of action of the rhodium carboxylate complexes are highly similar to that of a proteasome inhibitor. Further cellular and biochemical studies showed that rhodium carboxylate complexes induced an accumulation of ubiquitinated proteins, inhibited the proteolytic activities of purified 20S proteasome and proteasomal deubiquitinating enzyme. These results corroborate that the impairment of the ubiquitin-proteasome system is linked to the cytotoxic action of rhodium carboxylate complexes.
Silver is known to be an anti-inflammatory agent for topical treatment. A silver complex of N, N’-disubstituted cyclic thiourea that is reasonably stable towards reduced glutathionewas found to potently inhibit the NF-B transcriptional activity. Treatment of cells with silver thiourea inhibited TNF-α-stimulated IκB kinase activity, IκBα phosphorylation and degradation, nuclear translocation of NF-κB p65 and eventually the stimulated gene expression of inflammatory cytokines. Suppression of IκB kinase activity was associated with modification of sensitive cysteine residues and disruption of IκB kinase assembly. These data demonstrated that the inhibitory properties of Ag+ ions on an anti-inflammatory and anti-cancer drug target could be effectively delivered via the thiourea ligand.
Silver is also an antimicrobial metal, and this study was also extended to understand the silver-bacteria interaction using a silver resistant bacteria as a model. Many silver resistant bacteria often produce considerable amount of silver particles when exposed to high concentrations of silver salts but the mechanism of biosynthesis is not well understood. A silver resistant E. coli that displays active silver efflux was shown to synthesize zero-valent silver nanoparticles in the periplasmic space through reduction of silver ions under anaerobic conditions. As the microbial c-type cytochromes are known to mediate respiratory metal reduction, their role in the biosynthesis of silver nanoparticles was examined. A deletion mutant of the cytoplasmic membrane-anchored tetra-heme c-type cytochrome subunit of periplasmic nitrate reductase (NapC) showed marked reduction of accumulation of silver nanoparticles. This study identified a molecular mechanism of biosynthesis of silver nanoparticles that may have implication in bioenvironmental processes and synthetic biology of metal nanomaterials.published_or_final_version
Chemistry
Doctoral
Doctor of Philosophy
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Esposito, Breno Pannia. "Estudo dos produtos de reação entre carboxilatos de ródio (II) e amidas." Universidade de São Paulo, 1997. http://www.teses.usp.br/teses/disponiveis/46/46134/tde-03102006-141717/.
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Foram estudados os produtos da interação entre o acetato e o trifluoroacetato de ródio (respectivamente, Rh2(OAc)4 e Rh2(TFA)4) com amidas (formamida, FA; acetamida, AA; N-metil-acetamida, MA; benzamida, BA; N-fenil-acetamida, NFAA; trifluoroacetamida, TMA; ciclofosfamida, CFA), objetivando caracterização química e avaliação do potencial anti-tumor. Foram sintetizados por refluxo em clorofórmio dois adutos de Rh2(OAc)4 (Rh2(OAc)4-2FA e Rh2(OAc)4-2AA) e sete adutos inéditos de Rh2(TFA)4, de fórmula geral Rh2(TFA)4-2L (L = AA, BA, CFA, FA, MA, NFAA e TMA). Também obtivemos o novo amidato de Rh(II), Rh2(CF3CONH)4(CF3CONH2)2 (Rh2(TFACAM)4-2TMA), por fusão de Rh2(OAc)4 com TMA. Através da fusão de Rh2(TFA)4 com MA, obtivemos um composto que formulamos como Rh2(CF3COO)2(CH3CONCH3)2. Os resultados de análise elementar foram satisfatórios. Os adutos apresentaram bandas de absorção características dos carboxilatos de ródio (~ em 600, 450, 250 - ombro - e 220 nm). O modo de coordenação do ligante axial, pelo átomo de oxigênio da amida, foi determinado pela diminuição da freqüência de estiramento C-O na região do infravermelho (IV). Os amidatos apresentaram apenas uma banda na região do visível, e na região do IV os valores de?estiramentos característicos dos principais grupos orgânicos. Estudos comparativos dos espectros Raman mostraram que a freqüência Rh-Rh diminui ao se passar de um carboxilato para um amidato. Medidas de susceptibilidade magnética atestam o diamagnetismo de todas as moléculas (ligação Rh-Rh simples). O mecanismo de termodecomposição do Rh2(TFA)4 e dos seus adutos com amidas envolve mais de uma etapa, sendo que os intermediários podem apresentar estruturas do tipo Rh2(CF3COO)4-x(L)n (x e n = 1 ou 2). Avaliação do potencial citostático (frente a células U937, K562 e ascite de Ehrlich) e da DL50 (camundongos Balb-c) do complexo Rh2(TFACAM)4-2TMA mostraram atividade in vitro superior e toxicidade in vivo semelhante às da cisplatina.We studied the interaction products of two Rh carboxylates (acetate, AC; and trifluoroacetate, TFA) with amides (formamide, FA; acetamide, AA; N-methyl-acetamide, MA; benzamide, BA; N-phenyl-acetamide, NFAA; trifluoroacetamide, TMA; cyclophosphamide, CFA). Two adducts of AC (AC-2FA e AC-2AA) and seven new adducts of TFA (TFA-2FA, TFA-2AA, TFA-2MA, TFA-2BA, TFA-2NFAA, TFA-2TMA, TFA-2CFA) were synthesized by reflux in CHCl3 solution. We obtained also the new Rh(II) amidates Rh2(CF3CONH)4(CF3CONH2)2 (TFACAM-2TMA) and a compound formulated as Rh2(CF3COO)2(CH3CONCH3)2 (\"Semi-MACAM\"), by fusion of the appropriate reagents. Elemental microanalysis results were satisfactory. Thermal decomposition mechanism of TFA and its adducts involves more than one step, and the intermediates can exhibit structures as Rh2(CF3COO)4-x(L)x (x = 0 or 1). Citostatic potential evaluation (towards U937, K562 and Ehrlich ascites cells) and of LD50 (Balb-c mice) of the compound TFACAM-2TMA showed superior in vitro activity and similar in vivo toxicity when compared with cisplatin.
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Korom, Sasa. "Studies on Iridium(I), Rhodium(I) and Ruthenium(II) Metallocavitands Derived from Resorcin[4]arene." Doctoral thesis, Universitat Rovira i Virgili, 2015. http://hdl.handle.net/10803/319706.
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Aquesta tesis inclou els resultats de recerca bàsica de la química de metallocavitands.
El primer projecte descriu els efectes produïts per la constricció del complex organometàl•lic (THF-d8)•Ir(I)•COD en l’interior de la cavitat aromàtica de la octaamida cavitand d’en Rebek. L’inesperat comportament dinàmic del complex organometàl•lic inclòs dóna lloc a l’observació de sorprenents exemples d’isomerisme supramolecular .
El segon projecte gira entorn la síntesis d’una nova classe de heptaamida cavitants funcionalitzats amb una unitat de piridina . La coordinació de Rh(I)•COD amb la sèrie de heptamidas produeix complexes organometàl•lics mono catiònics amb diferent geometries de complexació. Els metalo-cavitands de Rh(I) obtinguts foren assajats com a catalitzadores en la reacció d’hidrogenació de norbornadiè.
El tercer projecte descriu el disseny, la síntesis i la caracterització d’un nou cavitand funcionalitzat amb un complex de Ru(II)•(H2O) terpiridina que conté com a lligand auxiliar 2-(fenilazo)piridina. El Ru(II)•(H2O) cavitand fou utilitzat com a catalitzador en la reacció d’epoxidació d’olefines i en la reacció d’oxidació d’alcohols primaris.Esta tesis contiene los resultados de tres estudios sobre la química de metalo-cavitandos. En el primer proyecto describe los efectos producidos por el confinamiento del complejo organometálico (THF-d8)•Ir(I)•COD en la cavidad aromática de la octamida cavitando de Rebek. El inesperado comportamiento dinámico que experimenta el complejo organometálico incluido dio lugar a la observación de ejemplos sorprendentes de isomerismo supramolecular. En el segundo proyecto se describe la síntesis de una nueva clase de heptaamida cavitandos funcionalizados con una unidad de piridina. La coordinación de Rh(I)•COD con la serie de heptaamidas produce complejos organometálicos monocatiónicos con diferentes geometrías de complejación. Los metalo-cavitandos de Rh(I) así obtenidos se usaron como catalizadores en la reacción de hidrogenación de norbornadieno. En el tercer proyecto se detalla el diseño, la síntesis y la caracterización de un nuevo cavitando funcionalizado con un complejo de Ru(II)•(H2O) terpiridina que contiene 2-(fenilazo)piridina como ligando auxiliar. El Ru(II)•(H2O) cavitando fue utilizado como catalizador en la reacción de epoxidación de olefinas y en la reacción de oxidación de alcoholes primarios.
This thesis includes the results of fundamental research on metallocavitand chemistry. The first project describes the effects produced by constraining the organometallic complex (THF-d8)•Ir(I)•COD into the aromatic cavity provided by Rebek’s octaamide cavitand. The unexpected dynamic behavior of the included organometallic complex led to the detection of surprising examples of supramolecular isomerism. The second project deals with the synthesis of an unprecedented series of pyridyl-decorated self-folding heptaamide cavitands. The coordination of Rh(I)•COD with the cavitand’s series produced a cationic organometallic complexes with different binding geometries. The produced Rh(I)-complexes were tested as catalysts in the hydrogenation of norbornadiene. The third project discloses the design, synthesis and characterization of a new cavitand functionalized with a terpyridine Ru(II)•(H2O) complex with 2-(phenylazo)pyridine as an ancillary ligand. The Ru(II)•(H2O) metallocavitand was used as a catalyst in the epoxidation reaction of olefins and the oxidation of primary alcohols.
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Lydon, Kevin M. "Asymmetric synthesis in insertion reactions of #alpha#-diazocarbonyl compounds catalysed by chiral rhodium (II) carboxylates." Thesis, Queen's University Belfast, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287443.
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Shore, Daniel Gordon Michael. "I. The Enantioselective Synthesis of Chiral Allenyl Carbonyl Compounds and Their Use as Synthetic Intermediates II. Rhodium-Catalyzed C-H Functionalization: Application to the Synthesis of 3-Carboxylindoles and Attempted Applications to Allenes." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19891.
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Allenes are unique compounds in organic chemistry by virtue of their adjacent,
orthogonal π-bonds. While of limited use in and of themselves, some classes of allenes have
found use in organic synthesis as building blocks for more complex products. Previous work in the Fagnou group has identified a silver lewis acid-catalyzed enantioselective isomerization protocol for the synthesis of allenyl esters and amides. This protocol has been subject to reproducibility issues, the source of which is explored in this thesis. Initial work into the development of a phase-transfer catalytic process for the isomerization of alkynyl amides is also
presented.
The use of allenyl esters in lactonization reactions has become more common in recent
years. The scope of the halolactonization of allenyl esters to form halobutenolides is explored here. The lactonization of allenyl carboxylic acids has also been demonstrated in the literature. The attempted synthesis of allenyl carboxylic acids via the oxidative deprotection of dimethoxybenzyl esters is also presented.
Indole is an important and biologically and medicinally relevant compound in organic
synthesis. Though many classical methods for its synthesis exist, the discovery of new, complex indole-containing compounds necessitates the development of efficient ways to synthesize indoles. Previous work in the Fagnou group has led to the discovery of a rhodium-catalyzed oxidative synthesis of indole with a key C-H functionalization step. This protocol has been applied to alkynyl esters to synthesize an array of 3-carboxylindoles in moderate to good yields.
The competency of allenes as an intra- and intermolecular coupling partner in a similar
rhodium-catalyzed hydroarylation reaction has also been explored, leading to the discovery that allenyl compounds are not tolerated in this reaction protocol.
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Esposito, Breno Pannia. "Interações de Complexos de Ródio(II) com Albumina Humana." Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/46/46134/tde-27092006-172252/.
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Vários complexos de ródio Rh2(L)4 (L = acetato, propionato, butirato, trifluoroaceta-to e trifluoroacetamidato) ligam-se à albumina de soro humana (HSA) em relações mola-res de aproximadamente 8:1. Medidas de dicroísmo circular mostraram que os carboxila-tos mais lipossolúveis (butirato e trifluoroacetato) provocaram as maiores alterações na estrutura secundária da HSA. As constantes de Stern-Volmer para a supressão de fluo-rescência da HSA por esses complexos também foram maiores para os compostos mais lipofílicos. O amidato lipossolúvel, Rh2(tfc)4, apresentou supressão intermediária e não provocou alterações estruturais. Isto mostra que é possível projetar metalofármacos anti-tumorais que se ligam a proteínas de transporte em grande quantidade, sem provocar al-terações estruturais importantes. Esses complexos tiveram também suas afinidades em relação à HSA determinadas por espectrofotometria, observando-se no caso dos alquil-carboxilatos uma correlação inversa com suas lipossolubilidades, o que sugere uma com-petição entre coordenação axial ao metal e interação hidrofóbica do ligante. A difusão dos complexos livres ou ligados à proteína para células de Ehrlich in vitro parece primordial-mente governada pelo caráter hidrofóbico do complexo. O complexo Rh2(tfc)4 apresentou afinidade pela proteína (K = 214,1), além de partição celular tanto em ausência (32,1%) como na presença (48,6%) de HSA. Desta forma, o composto HSA:Rh2(tfc)4 teve sua a-ção antitumoral investigada em camundongos Balb-c portadores de ascite de Ehrlich, mostrando que a HSA pode ser um reservatório para o complexo de ródio.Various divalent rhodium complexes Rh2(L)4 (L = acetate, propionate, butyrate, tri-fluoroacetate and trifluoroacetamidate) have been found to bind to non-defatted human serum albumin (HSA) at molar ratios about 8:1. The circular dichroism measurements showed that the more liposoluble carboxylates butyrate and trifluoroacetate caused the major alterations of the secondary structure of HSA. Stern-Volmer constants for the fluo-rescence quenching by these complexes were also higher for the lipophilic metal com-pounds. In the case of the rhodium carboxylates it was observed that their denaturating and quenching properties could be explained in terms of their liposolubilities: the higher their lipophilic characters, the higher their abilities to penetrate inside the protein frame-work leading to structural alterations, and the closer they could get to the Trp214 residue causing fluorescence quenching. The liposoluble amidate complex Rh2(tfc)4, presented an intermediate quenching and did not cause structural alterations in the protein, presumably not penetrating inside the peptidic backbone. This shows that it is possible to design new antitumor metal complexes which bind to a large extent to a transporter protein causing little structural damage. The affinities for human albumin of these five rhodium(II) comple-xes were determined by spectrophotometry. In the case of the alkylcarboxylates, an inver-se correlation of affinity with their liposolubilities was observed. Diffusion of the free or pro-tein-bound complexes into Ehrlich cells in vitro seems to be primarily governed by the hy-drophobic character of the complex. The complex Rh2(tfc)4 exhibited considerable affinity towards the protein (K = 214.1) as well as cell partition both in the absence (32.1%) and presence (48.6%) of HSA. The compound HSA:Rh2(tfc)4 has had its antitumoral action in tumor-bearing Balb-c mice investigated, showing that HSA can be a drug reservoir for the rhodium complex.
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Brown, Andrew Paul. "Studies of the role of tin(II) in the rhodium(I) chloride catalysed hydrocarbonylation of alkenes." Thesis, Durham University, 1994. http://etheses.dur.ac.uk/5532/.
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Batch catalytic and high pressure infra-red studies of catalytic systems have provided detailed information about the homogeneous rhodium-chloride catalysed hydrocarbonylation of ethene to form propanoic acid in CH(_3)COOH/c.HC1 at 180ºC and 60 bar pressure. [Rh(CO)(_2)Cl(_2)]- was shown to be an active catalyst for this process. Tin(ll) chloride as a co-catalyst was shown to have an effect on the rate of propanoic acid production for a rhodium-chloride catalytic process, but a clear promotional effect was only observed for systems employing a Sn:Rh molar ratio of 2: 1. Sn:Rh molar ratios higher than 2: 1 lead to a decrease in the selectivity for propanoic acid, while those lower than 2:1 result in catalytic activity consistent with [Rh(CO)(_2)Cl(_2)]- being an active species. The reactions of rhodium(I) carbonyl chlorides with tin(II) chlorides were carried out at atmospheric pressure to investigate the reaction chemistry between species present in the catalytic process. [Rh(CO)(_2)Cl(_2)]- and Rh(_2)(CO)(_4)Cl(_2) react with SnCl(_2) and SnCl(_3)- in both THF and CH(_2)Cl(_2) to form Rh(I)-CO-SnCl(_3) complexes. Infra-red and (^119)Sn NMR data identified the 5-coordinate complex [Rh(CO)(_2)(SnCl(_3)) (_3)](^2-)- as the favoured species formed in solution. Its crystal structure is reported. However, it appears to be related by a series of facile reactions, involving dissociation of SnCl(_3)(^-)- and CO groups, to several other 4 and 5-coordinate Rh(I)-CO-SnCl(-3) complexes. [Rh(CO)(SnCl(_3))(_4)](^3-), [Rh(CO)(SnCl(_3))(_2)Cl](^2-), and [Rh(CO)(_2)(SnCl(_3))X](^-) (X = Cl(^-) or SnCl(_3)(^-)) have been isolated from solution, often as mixtures along with [Rh(CO)(_2)(SnCl(_3))(_3)](^2-). Spectroscopic and X-ray crystallographic data indicated that SnCl(_3)(^-)- is a significant π- tacceptor ligand, thus explaining its ability to form 5-coordinate 18-electron rhodium(I) complexes. The effect of tin(II) chloride on the rhodium-chloride catalytic reaction is attributed to changes in π-acceptor and trans effect properties when SnC1(_3)(^-)- replaces chloride ligand(s). High pressure infra-red studies are consistent with both [Rh(CO)(_2)Cl(_2)](^-) and a Rh(I)CO- SnCl(_3) complex being catalytically active in a rhodium-tin-chloride system, and the carbonyl absorptions observed are consistent with [Rh(CO)(SnCl(_3))(_4)](^3-), [Rh(C0h(SnC(_3))(_3)](^2-) and [Rh(CO)(SnCl(_3))(_2)Cl](^2-) as catalytic precursors. The general predominance of [Rh(CO)(_2)(SnC1(_3))(_3)](^2-) in solution at atmospheric pressure and room temperature, suggests that it may be the favoured catalytic precursor, undergoing conversion to a catalytically active 16-electron Rh(I)-SnC1(_3) complex such as [Rh(CO)(_2)(SnCl(_3))X]- (X = Cl(^-) SnCl(_3)(^-)) via dissociation of SnCl(_3)-.
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Stace, Justin J. "Oxidative-Addition Reactions of Rhodium(I) Dimers and Platinum(II) Monomers; a Study to Understand a Novel Photochromic System." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1311773793.
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Mollin, Stefan [Verfasser], and Eric [Akademischer Betreuer] Meggers. "Oktaedrische Ruthenium(II)- und Rhodium(III)-Komplexe mit mehrzähnigen Liganden als Kinaseinhibitoren / Stefan Mollin. Betreuer: Eric Meggers." Marburg : Philipps-Universität Marburg, 2012. http://d-nb.info/102149884X/34.
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Jones, Lynn. "Selective preconcentration of platinum and rhodium from hydrochloric acid media containing tin (II) chloride using polyurethane foam." Master's thesis, University of Cape Town, 1987. http://hdl.handle.net/11427/17661.
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Includes bibliographical references.The potentially quantitative and selective sorption of chloro-(trichlorostannato)-platinum(II) and -rhodium (III/I) complex anions by polyurethane foams has been examined. Quantitative separation of platinum(II) from iridium and ruthenium has been achieved. Rhodium( III) is similarly sorbed by polyurethane foam in the presence of sufficient tin(II) chloride and-its clean separation from iridium has been achieved using this method. Ruthenium, although not significantly sorbed under the same conditions as platinum and rhodium, appears to inhibit the extraction of the rhodium(III/I)-tin(II) species. A procedure has been developed for the quantitative recovery of both platinum and rhodium. The polyurethane foams are dissolved in hot nitric acid, followed by flame AAS. Near-quantitative recovery of these metals has been achieved by means of foam stripping using a suitable eluent. The rate of formation of the chloro-(trichlorostannato)platinum( II) complex anions is rapid when PtCl₄²⁻ is treated with an excess of tin( II) chloride. On the other hand, the reaction of cis-Pt(NH₃)₂Cl₂ with stannous chloride is very slow and forcing conditions are required to achieve quantitative sorption of the platinum(II)-tin( II) species by polyurethane foams for this complex The potential of the foam to selectively extract platinum from solutions containing certain base metals was studied. Results obtained show that in all cases complete extraction of platinum was achieved. Of the base metals investigated, namely Fe( III), Co( II), Ni(II), Cu(II) and Zn(II), only copper(II) co-extracts to a small extent with the noble metal.
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Lloyd, Matthew. "Rhodium(II)-catalysed C–H insertion/olefination strategy towards α-methylene-γ-butyrolactones : applications in natural product synthesis." Thesis, University of York, 2016. http://etheses.whiterose.ac.uk/13069/.
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This Thesis describes the development of telescoped rhodium(II)-catalysed transformations of α-diazo(diethoxyphosphoryl)acetates for the formation of α-methylene-γ-butyrolactones. An overview of synthetic approaches to α-methylene-γ-butyrolactones is given in Chapter 1, in addition to a discussion of published Rh(II)-catalysed C–H insertion reactions. Previous efforts in the Taylor group have established effective methods for the synthesis of α-methylene-γ-butyrolactones, although these require relatively complex functionality in the precursors. The research in this Thesis focuses on the development of a one-pot Rh(II)-catalysed C–H insertion/olefination sequence for the synthesis of α-methylene-γ-butyrolactones III from α-diazo(diethoxyphosphoryl)acetates I, which are readily accessible from simple alcohols. The key C–H insertion step enables the formation of a new C–C bond in α-phosphonolactone II, via reaction of the rhodium carbenoid with a C–H bond typically considered completely unreactive. The scope of the reaction is explored in detail, concluding with the synthesis of two natural products, cedarmycins A and B (IV and V) and a Staphylococcus Aureus inhibitor VI (Chapter 2). The scope of the reaction was extended to the use of conformationally restricted substrates,facilitating the synthesis of α-methylene-γ-butyrolactones with complete diastereoselectivity,demonstrated through the synthesis of the natural product α-cyclocostunolide VII (Chapter 3). Finally, the development of a related procedure is described (Chapter 4). The rhodium(II)-catalysed cyclopropanation of allylic α-diazo(diethoxyphosphoryl)acetates is discussed as an alternative approach to the α-methylene-γ-butyrolactone framework. This work has been applied to the first total synthesis of peperomin E VIII as well as savinin IX and gadain X (Chapter 4).
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Nasrallah, Ali. "Complexe de Rhodium(II) et iode hypervalent en catalyse : époxydation d’alcènes et amination de liaisons C(sp³)-H." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS427.
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Cette thèse a pour but de développer de nouveaux procédés catalytiques en combinant de réactifs de l’iode hypervalent avec des complexes de rhodium(II).Le premier chapitre concerne l’observation de l’époxyde comme produit secondaire inatendu dans les conditions de transfert de nitrène catalytique, et le développement d’une nouvelle méthode de préparation d’époxydes qui combine un réactif de l’iode hypervalent(III) et un complexe de dirhodium(II). Le second chapitre vise le développement d’une méthode d’amination C(sp³)–H benzylique intermoléculaire énantiosélective,en utilisant un nouveau complexe de rhodium chiral et un nouveau sulfamate benzylique et l’application de cette méthode à grande échelle et sur des produits complexes.Le dernier chapitre du manuscrit décrit une réaction d’amination régiosélective de liaisons C(sp³)–H non activées d’alcanes par catalyse au rhodium (II), en utilisant une quantité stoechiométrique d’alcanes comme substratsThis thesis describes the development of new catalytic processes by combining hypervalent iodine reagents with rhodium (II) complexes.The first chapter concerns the observation of the epoxide as a unexpected product under catalytic nitrene transfer conditions, and the development of a new method to promote the epoxidation of alkenes by combining a reagent of hypervalent iodine (III) and a complex of dirhodium (II).The second chapter is centered on the development of a general method forasymmetric intermolecular benzylic C(sp³)–H amination by combining a chiral rhodium (II) catalyst and a benzyl sulfamate, and the application of this method on large scale.The third part of this work show the development of a regioselective C(sp³)–H amination of unactivated alkane by rhodium (II) catalysis, using a stoichiometric amount of alkane as the substrate
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Odom, Lindsay D. "Reactions of diazoketones catalyzed by rhodium (II) : synthesis of functionalized azetidines and tetrahydrofurans as potential protein kinase C inhibitors /." Full text available from ProQuest UM Digital Dissertations, 2006. http://0-proquest.umi.com.umiss.lib.olemiss.edu/pqdweb?index=0&did=1331395991&SrchMode=1&sid=8&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1218744025&clientId=22256.
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Witt, Suzanne Elizabeth. "Dirhodium(II,II) Complexes as Electrocatalysts for Sustainable Energy Applications: Tunable Selectivity For H+ or CO2 Reduction." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu150047691466017.
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Hammoud, Jana. "Evaluation des complexes dirhodium (II) tétraacétate-Carbène-N-Hétérocyclique pour la décomposition de diazoesters et applications en glycochimie Functionalization of GlucoPyranosides at position 5 by 1,5 C–H insertion of Rh(II)-Carbenes: Dramatic influence of the anomeric configuration." Thesis, Normandie, 2020. http://www.theses.fr/2020NORMIR03.
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Ces travaux de thèse ont concerné l’étude des propriétés catalytiques des complexes Rh₂L₄.NHC vis-à-vis des diazo esters, et leur application dans le domaine de la glycochimie. Nous avons tout d’abord développé une procédure expérimentale reproductible pour la préparation de ces complexes organométalliques. Par ailleurs, nous avons montré que le complexe Rh₂(OAc)₄.IMes était capable de décomposer de manière chimiosélective différentes familles de diazo esters, ouvrant ainsi la possibilité de la conception d’un système catalytique commutable. Dans le domaine de la glycochimie, les complexes Rh₂L₄.NHC ont permis d’amélioré les conditions expérimentales de la réaction de quaternarisation de la position anomèrique par fonctionnalisation de sa liaison C-H. Enfin, la quaternarisation de la position 5 de pyranosides par insertion 1,5 C-H d’un métallo-carbène de Rh(II) ancré sur la position primaire a été développéeThis work deals with the study of the catalytic properties of Rh₂L₄.NHC complexes towards diazoesters, and their application in the field of glycochemistry. We first developed a reproducible synthetic procedure for the preparation of these organometallic complexes. Furthermore, we have shown that the Rh₂(OAC)₄.IMes complexe was inducing the chemoselective decomposition of diazo esters, depending on their electronic properties. This unprecedented property opened the way to a switchable catalytic system. In the field of glycochemistry, the Rh₂L₄.NHC complexes made possible to improve the experimental conditions for the quaternization reaction of the anomeric position by C-H bond functionalization. Finally, the quaternization of position 5 of pyranosides by 1,5 C-H insertion of a Rh (II) metallo-carbene anchored on the primary position was developed
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Lefebvre, Jean-François. "Synthèse et propriétés de ligands de type carbène N-hétérocyclique conjugués à une porphyrines." Thesis, Montpellier 2, 2010. http://www.theses.fr/2010MON20141/document.
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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 ClIn 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
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Boquet, Vincent. "Aziridination énantiosélective et Amination C(sp³)-H chimiosélective catalysées par des complexes de rhodium(II) : développements méthodologiques et application à la fonctionnalisation tardive de produits naturels." Thesis, université Paris-Saclay, 2021. http://www.theses.fr/2021UPASF012.
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Cette thèse est consacrée au développement et à l’application de réactions d’aziridination et d’amination C(sp³)–H par transfert de nitrène catalysé au rhodium(II). Dans le premier chapitre, la mise au point d’une réaction d’aziridination d’alcènes intermoléculaire énantiosélective est décrite. Cette réaction est basée sur l’association du sulfamate dérivé du 4-tert-butylphénol et d’un complexe bimétallique de rhodium(II) chiral dérivé de la tert-leucine. Le champ d’application de cette méthode et quelque exemples d’utilisations des aziridines énantioenrichies synthétisées sont présentés. Le deuxième chapitre concerne le développement d’une réaction d’amination intermoléculaire chimiosélective de liaisons C(sp³)–H tertiaires en présence de liaisons benzyliques. Cette sélectivité singulière est obtenue par la combinaison des réactifs décrits au premier chapitre. Le champ d’application, incluant des dérivés iso-butyl et iso-amylbenzène, ainsi que l’intérêt de cette nouvelle réaction sont présentés. Dans une deuxième partie, le développement d’une réaction d’amination C(sp³)–H régiosélective d’alcanes est décrit. Cette méthode permet la synthèse efficace d’amines tertiaires en utilisant une quantité stœchiométrique d’alcane. Le troisième chapitre concerne la fonctionnalisation tardive de dérivés de l’acide fislatifolique à l’aide des réactions de transfert de nitrène. L’application des méthodologies développées au laboratoire d’accueil a permis la synthèse de 11 analogues aminés avec de bons rendements et sélectivités. Parmi ces produits, deux dérivés présentent une activité biologique différente par rapport à celle du composé parentThis thesis describes the development and application of aziridination and C(sp³)–H amination reactions involving rhodium(II) catalyzed nitrene transfers. In the first chapter, the development of an enantioselective intermolecular alkene aziridination reaction is reported. This reaction is based on the use of sulfamate derived from 4-tert-butylphenol as the nitrene precursor, and a chiral dirhodium(II) complexe derived from tert-leucine. The scope of this transformation and the some synthetic modifications of the enantioenriched aziridines are presented. The second chapter is centered on the development of a catalyst-controlled selective C(sp³)–H amination of tertiary C–H bonds in the presence of benzylic C–H bonds. This peculiar selectivity is obtained with the combinaison of the same reagents used in the first chapter. The scope, involving isobutyl and isoamylbenzene derivatives, and the interest of this new reaction are described. In a second part, the development of a regioselective C(sp³)–H amination of alkanes is described. This method enables the efficient synthesis of tertiary amines by using alkanes as the limiting components. The third part presents the late-stage functionalization of fislatifolic acid derivatives via catalytic nitrene transfer reactions. Application of methods developped in our team has lead to the synthesis of 11 aminated analogues with good yields, selectivities, and interesting biological properties
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Gallou, Isabelle. "Selective palladium- and rhodium-catalyzed processes : I. enantioselective synthesis of tetrahydroquinolines, II. the asymmetric hydroformylation reaction, III. silylstannylation-cyclization of diynes and alleneynes /." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486457871782787.
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Yu, Qing. "The rhodium(II)-catalyzed intramolecular tertiary C-H insertion of diazoacetates, application in the total synthesis of alkaloids possessing a chiral quaternary carbon center." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ65793.pdf.
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Smith, Elizabeth J. "An investigation into the formation of a variety of C3 organometallic species via the isomerisation of alkynes by ruthenium (II) and rhodium (I) complexes." Thesis, University of York, 2014. http://etheses.whiterose.ac.uk/6988/.
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A novel synthetic route for the formation of ruthenium complexes [Ru(κ2-OAc)2(PR3)2] 1 has been developed. These complexes have been used to investigate the stoichiometric formation of geminal alkenes from the reaction of triphenylphosphine complex [Ru(κ2-OAc)2(PPh3)2] 1a with propargylic alcohols. It was found that the reaction was promoted by the use of the bulky, electron-rich triisopropylphosphine. This lead to the proposal that the mechanism involves a cationic intermediate and the suggested structure of this intermediate was vinyl carbene [Ru(κ2 OAc)(OC{Me}OCC{H}=CH2)(PPh3)2][BF4] 26. A series of analogues of 26 were synthesised and their reactivity investigated. Whilst no evidence was obtained of their being involved in the transformation of propargylic alcohols to alkenes, it was found that their reactivity can be tuned by changing the substituents on the vinyl moiety. Deprotonation leads to the formation of either the allenylidene complex [Ru(κ2-OAc)(κ1-OAc)(PPh3)2(=C=C=CPh2)] 30 or the vinyl vinylidene complexes [Ru(κ2-OAc)(κ1-OAc)(PPh3)2(=C=CH-C(R)=CH2)] 32 (R = Ph, Me). A theoretical investigation into this reaction has led to the suggestion that vinyl carbene complexes like 26 could be important reaction intermediates in the formation of allenylidenes from propargylic alcohols. The reactivity of 1a towards the triphenylphosphine-substituted alkyne [HC≡CCH2PPh3]+ 39 has also been investigated. It has been found that this propargylic phosphonium is particularly prone to isomerisation to its allene isomer [H2C=C=CHPPh3]+ 40 and, as a result, reaction with organometallic precursors leads primarily to the formation of the allene complexes [Ru(κ2 OAc)(κ1 OAc)(η2 H2C=C=CHPPh3)(PPh3)2][BF4] 45a and [RhCl(η2 H2C=C=CHPPh3)(PiPr3)2][BPh4] 60. Experimental and theoretical investigations have concluded that the isomerisation is spontaneous (the allene is 37 kJ mol-1 more stable than the alkyne) and not metal promoted. It is however counter-ion dependant and use of the tetraphenylborate salt 39c slows the process enough for novel vinylidene complexes [Ru(κ2-OAc)(κ1-OAc)(C=C=CHCH2PPh3)(PPh3)2][BPh4] 38 and [RhCl(C=C=CHCH2PPh3)(PiPr3)2][BPh4] 63 to be synthesised.
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GUERREIRO, PATRICIO. "Hydrogenation asymetrique en phase homogene a l'aide de complexes chiraux du ruthenium(ii) et du rhodium(i) : synthese d'alcaloides monohydroxyles synthese et recyclage de catalyseurs." Paris 6, 1999. http://www.theses.fr/1999PA066686.
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L'hydrogenation asymetrique est un outil de choix pour creer un centre stereogene sur un carbone tertiaire. Elle est utilisee dans de nombreuses syntheses de produits d'interet biologique notamment au niveau industriel. Cette these decrit l'utilisation de catalyseurs chiraux du ruthenium(ii) prepares selon une methode simple developpee au laboratoire en hydrogenation. Les bonnes enantioselectivites obtenues pour l'hydrogenation de -cetoesters derives de la proline et de l'acide pipecolique ont permis d'elaborer une voie de synthese simple, rapide et stereocontrolee d'heterocycles azotes monohydroxyles. Nous avons realise avec succes la synthese de differents bicycles azotes comme la (1r,8r)-1-hydroxypyrrolizidine ou les (1s,8as) et (1r,8as)-1-hydroxyindolizidines et celle d'un alcaloide : la (+)-()-conhydrine. Dans le but d'obtenir des systemes catalytiques du ruthenium(ii) et du rhodium(i) recyclables en phase homogene, nous avons prepare des ligands hydrosolubles cationiques originaux analogues au binap et fonctionnalises par des groupements ammonium ou guanidinium. Ces ligands ont permis la preparation de catalyseurs du rhodium et du ruthenium(ii) efficaces en hydrogenation asymetrique de liaisons c=o et c=c, non seulement en terme de reactivite mais aussi en terme d'enantioselectivite. Les produits sont aisement separes du systeme catalytique par extraction et differents complexes ont ete recycles efficacement. Nous avons developpe un systeme catalytique par greffage de deux ligands (le degphos et le 6,6-diaminobinap) sur poly(ethylene glycol). Nous avons mis au point une methode efficace de recyclage des complexes chiraux (m-peg-p*p)rubr 2 et (m-peg-p*p)rhotf en hydrogenation asymetrique de liaisons c=o et c=c. L'activite catalytique est maintenue sur plusieurs cycles et l'enantioselectivite de la reaction est conservee.
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Morris, David. "Design and Modification of Half-Sandwich Ir(III), Rh(III), and Ru(II) Amino Acid Complexes for Application in Asymmetric Transfer Hydrogenation Reactions." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/71819.
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This dissertation describes the design and synthesis of a series of half-sandwich amino acid complexes of the form), (aa = α-amino carboxylate), and their utility as asymmetric transfer hydrogenation catalysts of ketones. Variation of the metal center, the n-ring, and the aa was used to tune these systems for specific sets of ketones. Upon reaction with homochiral]s, the ligand environment in all of these complexes is pseudotetrahedral, leading to stereogenic metal ions (SM, RM). The addition of another stereogenic center from the amino acid ligand (the carbon, RC or SC;glycine) gives rise to two pairs of diastereomeric complexes.Ph. D.
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SILVA, Matheus Oliveira da. "Succinato de ródio (II): síntese, caracterização e adsorção em nanopartículas de maghemita." Universidade Federal de Goiás, 2012. http://repositorio.bc.ufg.br/tede/handle/tde/1048.
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Previous issue date: 2012-08-13In this work it was described the synthesis and characterization of rhodium(II) succinate complex unpublished and adsorption study in maghemite nanoparticles. The rhodium(II) succinate was synthesized from a precursor rhodium(II) carboxylate, rhodium(II) trifluoracetate with a yield of 48.2%. The complex has become completely soluble in aqueous medium only when neutralized with 0,01 molL-1 NaOH solution to produce the sodium rhodium(II) succinate. The complex was characterized as the composition and structure by C and H elemental and thermogravimetric analysis, potentiometric titration, infrared and UV/visible spectroscopy. The data agree with a dimeric structure with four free carboxyl groups and suggest the molecular formulas [Rh2(O4C4H5)4(H2O)4] and [Na4Rh2(O4C4H4)4(H2O)5] to the rhodium(II) succinate and sodium rhodium(II) succinate respectively. Magnetite nanoparticles in aqueous media was prepared by coprecipitation method of Fe2+ and Fe3+ ion which was oxidized with oxygen gas. The solid obtained was characterized as crystalline phase by X-ray diffraction and as structure by infrared spectroscopy. The mean diameter of the nanoparticles (8 nm) was calculated by the Sherrer equation and lattice parameter was obtained through UnitCell program. It was obtained adsorption isotherm witch profile suggests the formation of multilayer adsorption having physical and chemical adsorption. The chemical adsorption was confirmed by infrared spectroscopy. The experimental data corresponding to monolayer were best fitted by the Freundlich adsorption isotherm with linear coefficient, R2, equal to 0,965. The functionalized nanoparticles were evaluated by measuring colloidal stability through hydrodynamic diameter and their surface properties by zeta potential measurements. The data showed strong dependence of the shifting of the IEP and the range of colloidal stability as a function of the amount of adsorbed complex and pH.
Neste trabalho foi descrito a síntese e caracterização do complexo inédito succinato de ródio (II) e um estudo da adsorção deste complexo em nanopartículas de maghemita. O succinato de ródio (II) foi sintetizado a partir de um carboxilato de ródio precursor, o trifluoracetato de ródio (II), com rendimento de 48,2%. O complexo tornou-se completamente solúvel em meio aquoso somente quando neutralizado com solução de NaOH 0,01 molL-1 produzindo o succinato de ródio (II) de sódio. O complexo foi caracterizado quanto à composição e estrutura por análise elementar de C e H, análise termogravimétrica, titulação potenciométrica, espectroscopia na região do infravermelho e na região do UV/VIS. Os dados obtidos concordam com uma estrutura dimérica com quatro grupos carboxílicos livres e sugerem as fórmulas moleculares [Rh2(O4C4H5)4(H2O)4] e [Na4Rh2(O4C4H4)4(H2O)5] para o succinato de ródio (II) e succinato de ródio (II) de sódio, respectivamente. Foi preparada uma suspensão de nanopartículas de magnetita pelo método da coprecipitação em meio alcalino dos íons Fe2+ e Fe3+ a qual foi oxidada à maghemita com gás oxigênio. O sólido obtido foi caracterizado quanto à fase cristalina por difratometria de raios-X e quanto a estrutura por espectroscopia na região do infravermelho. O diâmetro médio das nanopartículas (8 nm) foi calculado pela equação de Sherrer e o parâmetro de rede foi obtido pelo programa UnitCell. Foi obtida a isoterma de adsorção cujo perfil sugere a formação de múltiplas camadas de adsorção havendo adsorção química e física. A adsorção química foi confirmada por espectroscopia na região do infravermelho. Os dados experimentais correspondentes a monocamada se ajustaram melhor ao modelo de Freundlich com coeficiente de regressão linear, R2, igual a 0.965. As nanopartículas funcionalizadas foram avaliadas quanto a estabilidade coloidal por medida de diâmetro hidrodinâmico e suas propriedades de superfície por medidas de potencial zeta. Os dados mostraram forte dependência do deslocamento do IEP e da faixa de estabilidade coloidal em função do teor de complexo adsorvido e do pH.
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Azambuja, Francisco de 1986. "Ativações C-H catalisadas por Pd(II) e Rh(III) : estudos metodológicos e do mecanismo para a síntese de diariletanos e congêneres e avaliações da sua atividade biológica." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249877.
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Orientador: Carlos Roque Duarte CorreiaTese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: Neste trabalho, ativações C-H catalisadas por Pd(II) e Rh(III) foram exploradas para a obtenção de moléculas com potencial atividade biológica, em especial 1,1- e 1,2-diariletanos. Para o paládio, foi investigada a hidroarilação de alcinos de Fujiwara como um método rápido, brando e direto para a obtenção de ?-aril-?-heteroaril acrilatos. Inicialmente, o mecanismo desta reação foi estudada através de estudos de espectrometria de massas e ressonância magnética nuclear para elucidar a atuação do catalisador e os fatores envolvidos na estereosseletividade. Após este estudo, as condições reacionais foram reavaliadas para preparação de ?-aril-?-heteroaril acrilatos em bons rendimentos e seletividades. O paládio também foi usado como catalisador de arilações de Heck-Matsuda empregadas como etapa-chave na síntese de anidridos maleicos diarilados, a partir dos quais novos análogos de combretastatina A4 foram preparados. Estes novos análogos e os adutos da hidroarilação de alcinos de Fujiwara foram submetidos a testes de atividade antiproliferativa em células tumorais humanas. De maneira geral, os produtos de Fujiwara apresentaram melhores perfis de atividades, em especial para linhagens de células de rim e ovário, enquanto que os derivados de anidrido maleico diarilado mostraram-se muito pouco ativos para todas as linhagens. Esta ausência de atividade foi atribuída a interações estéreas desfavoráveis detectadas em estudos preliminares de docagem. Por último, ativações C-H catalisadas por 1,2,3,4,5-pentametilciclopentadienilródio(III) ([Cp*Rh(III)]) foram estudadas em dois projetos diferentes, um envolvendo 1,3-diinos e outro com ?-halo/pseudohalocetonas como parceiros de acoplamento, para a obtenção de diversos bis-heterociclos adjacentes e N-heterociclos monossubstituídos, respectivamente, com ênfase à preparação de núcleos isoquinolona
Abstract: New Pd(II) and Rh(III) catalysed C-H activations methods were developed to the obtaining of potential biologically active molecules, particularly 1,1- e 1,2-diarylethanes. With palladium, the Fujiwara¿s hydroarylation of alkynes was investigated as a fast, mild and direct method to the synthesis of ?-aryl-?-heteroaryl acrylates. Initially, the mechanism of this reaction was studied using nuclear magnetic resonance and mass spectrometry to elucidate the catalyst role and the key factors controlling the stereoselectivity. After, the reaction conditions were optimized in order to prepare the ?-aryl-?-heteroaryl acrylates in good yields and selectivities. The palladium was also applied as catalyst to the Heck-Matsuda arylations employed as the key step to the synthesis of non-symmetric diaryl maleic anhydrides. From such compounds new combretastatin A4 analogs were produced. These new compounds and the Fujiwara adducts were tested against several human tumor cells. The results were much better to the Fujiwara products, especially to kidney and ovary tumor cell lines. In contrast, the diaryl maleic anhydrides derivatives showed very low activity for all kinds of cells tested. This absence of activity was attributed to unfavorable steric interactions detected in preliminary docking studies. Last, the C-H activations catalysed by 1,2,3,4,5-pentamethylciclopentadienylrhodium(III) ([Cp*Rh(III)]) were explored in two different projects: 1) the C-H activation/1,3-diyne strategy to the synthesis of adjacent bis-heterocycles and 2) ?-halo/pseudohaloketones as oxidized alkyne equivalents to the selectively preparation of monosubstituted N-heterocycles, in particular the isoquinolone core
Doutorado
Quimica Organica
Doutor em Ciências
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Nkabyo, Henry Ane. "A study on the reversible photo-induced isomerisation of platinum(II) and palladium(II) complexes of the N,N-dialkyl-N’-acyl(aroyl)thioureas with reversed-phase HPLC separation from related rhodium(III), ruthenium(III) and iridium(III) complexes." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86773.
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Frantz, Alicia J. "Approaches to the Synthesis of the Natural Products, Azaphorbol and Frondosin B, via Diazo Decomposition Reactions." Ohio University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1478781611670221.
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Nunes, Eloiza da Silva. "Citrato de rodio (II): síntese, caracterização, adsorção em nanopartículas de maguemita e preparação de fluidos magnéticos." Universidade Federal de Goiás, 2010. http://repositorio.bc.ufg.br/tede/handle/tde/2920.
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In this work are described the synthesis and characterization of dinuclear rhodium(II) citrate, adsorption study in maghemite nanoparticles, and preparation of nanoparticles-modified based magnetic fluids. Rhodium(II) citrate has significant antitumor activity being promissory to cancer chemotherapy. Due to the existence of free functional groups in its molecular structure this complex has capacity to functionalize iron oxide nanoparticles to produce drug-particles formulations. The modified nanoparticles show features of biocompatibility suitable to use the system in medical applications. Rhodium(II) citrate was synthesized by an exchange reaction of trifluoroacetate ligands from the precursor rhodium(II) trifluoroacetate by citrate ligands. The products were characterized by C and H elemental and thermogravimetric analysis, mass spectrometry, and infrared, UV/visible and 13C nuclear magnetic resonance spectroscopy. The results are consistent with the formation of dinuclear structure characteristic for rhodium(II) carboxylates. Changing the synthesis conditions were obtained products with stoichiometries [Rh2(H2cit)2(H2O)4] and [Rh2(H2cit)4(H2O)2]. The results and compounds solubility observations suggest that the first one occur as a coordination polymer. The second one showed composition e solubility behavior consistent with the formation of monomeric units. Maghemite nanoparticles with size mean between 5 and 7 nm were obtained through alkaline coprecipitation of Fe2+ and Fe3+ ions with further oxidation with oxygen gas. The solids were characterized by X-ray difratometry and the Scherrer relation was use to calculate the crystallite size mean. Adsorption experimental data were adjusted to Langmuir model and linear coefficients obtained, R2, were greater than 0,99. Functionalized nanoparticles were dispersed into water producing a stable colloid. Dispersion s characterization was performed by absorbance, zeta potential, and hydrodynamic diameter measurements. Surface properties and colloidal behavior of functionalized nanoparticles are much affected by adsorbed species. The colloidal stability of the magnetic fluids is dependent on the adsorbed amounts of rhodium(II) citrate and pH. When the adsorbed amount of rhodium(II) citrate is next to saturation, the magnetic fluids are stable in pH over 3 and show hydrodynamic diameter around 60 nm. Fluids colloidal stability is preserved against physiologic saline solution, PBS buffer, and fetal bovine serum over a period of 30 days.
Neste trabalho estão descritos a síntese e a caracterização do complexo dimérico citrato de ródio(II), estudo de sua adsorção em nanopartículas de maghemita e a preparação de fluidos magnéticos á base de nanopartículas modificadas com o complexo. O citrato de ródio (II) apresenta significante atividade antitumor sendo promissor para aplicação na quimioterapia do câncer. Devido à existência de grupos funcionais livres em sua estrutura molecular esse complexo possui capacidade de funcionalizar nanopartículas de óxidos de ferro para produzir formulações droga-partícula. As nanopartículas modificadas apresentam características de biocompatibilidade adequadas para utilização do sistema em aplicações médicas. O citrato de ródio(II) foi sintetizado via reação de troca de ligantes trifluoroacetato do precursor trifluoroacetato de ródio(II) por citrato. Os produtos foram caracterizados por análise elementar de C e H e termogravimétrica, espectrometria de massas e espectroscopia nas regiões do UV/visível e infravermelho e ressonância magnética nuclear de 13C. Os resultados são consistentes com a formação da estrutura dimérica. Variando-se as condições de síntese pode-se obter produtos com estequiometrias [Rh2(H2cit)2(H2O)4] e [Rh2(H2cit)4(H2O)2]. Os resultados somados às observações sobre a solubilidade dos compostos sugerem que o primeiro ocorre como um polímero de coordenação. O segundo composto apresentou características de composição e solubilidade coerente com a formação de unidades dimetálicas monoméricas. Foram obtidas nanopartículas de maghemita com diâmetros entre 5 e 7 nm através do método de coprecipitação de íons Fe2+ e Fe3+ em meio alcalino com posterior oxidação com oxigênio gasoso. Os sólidos foram caracterizados por difratometria de raios-X e o diâmetro de cristalito calculado pela equação de Scherrer. Os dados experimentais de adsorção de citrato de ródio(II) em maghemita foram ajustados ao modelo de Langmuir sendo obtido coeficiente de regressão linear, R2, maior que 0,99. As nanopartículas funcionalizadas foram dispersas em água obtendo-se um colóide estável. As dispersões foram caracterizadas por medidas de absorvância, potencial zeta e de diâmetro hidrodinâmico. As propriedades de superfície bem como o comportamento coloidal das nanopartículas funcionalizadas são influenciadas pelas espécies adsorvidas. A estabilidade coloidal dos sóis obtidos é dependente das quantidades de citrato de ródio(II) adsorvida e do pH. Quando a quantidade de citrato de ródio adsorvida é próxima da capacidade de adsorção, os fluidos magnéticos obtidos apresentam estáveis em pH acima de 3 com diâmetros hidrodinâmicos próximos de 60 nm. A estabilidade coloidal dos fluidos obtidos é preservada frente a soluções de soro fisiológico, tampão PBS e soro fetal bovino por períodos superiores a 30 dias.
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Negrón, Ana Cecilia Valderrama. "Síntese e caracterização de carboxilatos de Rh(II) e seus adutos com metronidazol: ensaios biológicos com vistas à vtividade radiossensibilizadora de tumores." Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/46/46134/tde-01092014-164032/.
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Radiossensibilizadores são definidos como agentes químicos que aumentam a sensibilidade das células hipóxicas à radiação, visando o aumento da eficácia da radioterapia no tratamento do câncer. Alguns Carboxilatos de Rh (II) e compostos nitroimidazólicos têm sido testados como radiossensibilizadores em doses elevadas de radiação, obtendo-se resultados significativos. Neste trabalho, foram sintetizados vários carboxilatos e um amidato de Rh (II): propionato, butirato, trifluoroacetato, citrato e trifluoroacetamidato, assim como os seus respectivos adutos com metronidazol, de fórmula geral: [Rh2(RCOO)4metro2] (R = CH3, C2H5, C3H7, C5 H7O5, e CF3) para o caso dos carboxilatos e [Rh2(CF3CONH) 4 metro2] para o aduto de trifluoroacetamidato. Os compostos foram caracterizados por análise elementar, espectroscopia eletrônica, infravermelho e de ressonância magnética nuclear de próton. O resultado desta caracterização permitiu estabelecer as rotas de síntese confirmando a formação dos carboxilatos tipo ponte e a presença do metronidazol nas posições axiais, numa relação 1:2. O efeito radiossensibilizador desses complexos de Rh (II) foi testado in vitro, irradiando-se, em atmosfera hipóxica, células de ovário de hamster chinês (CHO k1), na presença dos complexos, utilizando-se raios gama provenientes de uma fonte de 60Co, com doses de 2,7 e 4,3 Gy. Foi realizado teste de citotoxicidade para determinar as concentrações atóxicas de cada composto, eliminando a possibilidade de morte celular devido ao efeito tóxico dos mesmos. Na dose 2,7 Gy não houve nenhum efeito interessante; já com a dose de 4,3 Gy o [Rh2(CH3 COO)4] mostrou uma atividade radiossensibilizadora maior do que nos demais complexos. Os resultados foram semelhantes aos obtidos na literatura com doses de radiação até 10 vezes maiores. Devido à ausência de mudanças significativas no efeito radiossensibilizador entre os carboxilatos e amidato e seus respectivos adutos com metronidazol, foi determinada a constante de formação destes últimos, demonstrando que os mesmos sofrem decomposição quando em solução aquosa diluída.Radiosensitizers are chemical agents that enhance the radiation sensitivity of hipoxic tumor cells aiming to better radiotherapy efficacy in the treatment of cancer. Some Rhodium (II) carboxylates and its adducts with nitroimidazole derivatives, have been tested as radiosensitizers in high doses of radiation, being obtained significant results. In this work, several Rhodium carboxylates and one Rhodium amidate previously described were synthesized: propionate, trifluoroacetate, citrate and , trifluoroacetamidate, as well as their respective adducts with nitroimidazole of general formula [Rh2(RCOO)4metro2] for the carboxylates and [Rh2(CF3CONH)4metro2] for the trifluoroacetamidate adduct. The compositions where characterized by elementary analysis, electronic and infrared spectroscopy and proton nuclear magnetic resonance. The results of that characterization allowed us to establish the synthesis routes and confirm the bridge type structure of the Rodhium compounds, beyond the presence of the metronidazole at the axial positions in the proportions of 1:2. The radiosensitizing effects of these Rh (II) complexes were tested in vitro by irradiation of Chinese hamster (CHO k1) cells under hipoxic atmosphere in the presence of the complexes, using gamma rays from a 60Co source and doses of 2,7 and 4,3 Gy. A cytotoxicity test has been performed to determinate the non-toxic concentrations of these compounds, in order to rule out the possibility of cellular death induced by the complexe´s cytotoxicity. A 2,7 Gy dose showed no interesting effects but under a 4,3 Gy dose, the complex Rh2(CH3 COO)4 showed a higher radiosensitizing effect than the order compounds and close to previously reported effects which required high radiation doses. As there was not a significant change in the radiosensitizing effect between the carboxylate and the amidate and their respective metronidazole adducts it was performed the measurement of the formation constant of that adducts. The results of that measurements gave evidence of adduct decomposition when in dilute aqueous solution.
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McLeod, Douglas Dale. "Some studies on asymmetric induction and double asymmetric induction of the rhodium(II)-catalyzed carbon-hydrogen insertion reaction of alpha-diazoacetamides and alpha-diazo-alpha-(methoxycarbonyl)acetates and the synthesis of (2S, 3R)-3-amino-2-hydroxydecanoic acid." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq39147.pdf.
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