Academic literature on the topic 'Complexos de rodi'
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Journal articles on the topic "Complexos de rodi"
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Paris, Sophie, Jean-Paul Debeaupuis, Reto Crameri, Marilyn Carey, Franck Charlès, Marie Christine Prévost, Christine Schmitt, Bruno Philippe, and Jean Paul Latgé. "Conidial Hydrophobins of Aspergillus fumigatus." Applied and Environmental Microbiology 69, no. 3 (March 2003): 1581–88. http://dx.doi.org/10.1128/aem.69.3.1581-1588.2003.
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ABSTRACT The surface of Aspergillus fumigatus conidia, the first structure recognized by the host immune system, is covered by rodlets. We report that this outer cell wall layer contains two hydrophobins, RodAp and RodBp, which are found as highly insoluble complexes. The RODA gene was previously characterized, and ΔrodA conidia do not display a rodlet layer (N. Thau, M. Monod, B. Crestani, C. Rolland, G. Tronchin, J. P. Latgé, and S. Paris, Infect. Immun. 62:4380-4388, 1994). The RODB gene was cloned and disrupted. RodBp was highly homologous to RodAp and different from DewAp of A. nidulans. ΔrodB conidia had a rodlet layer similar to that of the wild-type conidia. Therefore, unlike RodAp, RodBp is not required for rodlet formation. The surface of ΔrodA conidia is granular; in contrast, an amorphous layer is present at the surface of the conidia of the ΔrodA ΔrodB double mutant. These data show that RodBp plays a role in the structure of the conidial cell wall. Moreover, rodletless mutants are more sensitive to killing by alveolar macrophages, suggesting that RodAp or the rodlet structure is involved in the resistance to host cells.
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Figueira, João, Wojciech Czardybon, José Carlos Mesquita, João Rodrigues, Fernando Lahoz, Luca Russo, Arto Valkonen, and Kari Rissanen. "Synthesis, characterization and solid-state photoluminescence studies of six alkoxy phenylene ethynylene dinuclear palladium(ii) rods." Dalton Transactions 44, no. 9 (2015): 4003–15. http://dx.doi.org/10.1039/c4dt00493k.
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Sandroni, Carlos. "Samba de roda, patrimônio imaterial da humanidade." Estudos Avançados 24, no. 69 (2010): 373–88. http://dx.doi.org/10.1590/s0103-40142010000200023.
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Em 2005, o samba de roda, forma musical-coreográfica da região do Recôncavo, na Bahia, foi incluída pela Unesco na sua III Declaração de Obras-Primas do Patrimônio Imaterial da Humanidade. Essa candidatura vitoriosa foi construída num processo complexo, que envolveu agentes de políticas públicas, antropólogos, etnomusicólogos e, especialmente, sambadores e sambadoras do Recôncavo. A candidatura envolveu a elaboração de um Plano de Ação, previsto para cinco anos, para a salvaguarda do samba de roda no Recôncavo. No presente texto, depois de tratar brevemente do processo que levou à premiação da Unesco, são abordadas sobretudo questões suscitadas pela implementação do Plano de Ação, que se estruturou em torno de quatro "eixos": organização dos sambadores do Recôncavo, transmissão, difusão e documentação do samba de roda.
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Bowers, Philip L. "The upper Perron method for labelled complexes with applications to circle packings." Mathematical Proceedings of the Cambridge Philosophical Society 114, no. 2 (September 1993): 321–45. http://dx.doi.org/10.1017/s0305004100071619.
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The construction of geometric surfaces via labelled complexes was introduced by Thurston[16, chapter 13], and subsequent applications and developments have appeared in [1, 3, 4, 5, 14, 15]. The basic idea of using labelled complexes to produce geometric structures is that the vertices of a simplicial triangulation of a surface can be labelled with positive real numbers that collectively determine a metric of constant curvature ±1 or 0, with possible singularities at vertices, by using the label values to identify 2-simplices of the triangulation with geometric triangles. Beardon and Stephenson[1] developed a particularly simple method for producing non-singular surfaces via labelled complexes that is modelled after the classical Perron method for producing harmonic functions, and they applied their method in [2] to construct a fairly comprehensive theory of circle packings in general Riemann surfaces. This Perron method was developed more fully by Stephenson and the author in [3, 4] and applied to the study of circle packing points in moduli space. At about the same time and independently of Beardon, Stephenson, and Bowers, Carter and Rodin [5] and Doyle [8] developed the method for flat surfaces and Minda and Rodin [14] developed the method for finite type surfaces. Minda and Rodin [14] applied their development to give partial solutions to the labelled complex version of the classical Schwarz-Picard problem that concerns the construction of singular hyperbolic metrics on surfaces with prescribed singularities. In this paper, we modify the aforementioned approaches and examine the upper Perron method for producing non-singular geometric surfaces. This upper method has several advantages over the Perron method as developed previously and provides a complete solution to the labelled complex version of the Schwarz-Picard problem.
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Rees-Isele, Luitgard, Hans-Peter Winkler, and Egbert Keller. "In Search of the True Structure of the Sodium Chromium Alum II: Crystal Growth and Structure of the Double Salt NaCr(SO4)2(H2O)6·(CH3OH)0.6(2)· (H2O)1.5(5)." Zeitschrift für Naturforschung B 68, no. 12 (December 1, 2013): 1288–94. http://dx.doi.org/10.5560/znb.2013-3200.
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Attempts to crystallize the sodium chromium alum, NaCr(SO4)2(H2O)12, from water=methanol solutions at temperatures around 281 K yielded crystals of the title compound instead. Their monoclinic structure can be described as a centered rectangular array of linear {1∞}[Na(SO4)2]3- rods aligned parallel to [001] with vicinal rods held together by columns of isolated [Cr(H2O)6]3+ complexes. The structure forms channels parallel to [001] which are occupied by methanol and water molecules with atomic site occupancy factors of 1/5 and less. Various attempts to crystallize the compound or the sodium chromium alum from purely aqueous solutions remained unsuccessful
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Triantis, Charalampos, Antonio Shegani, Christos Kiritsis, Catherine Raptopoulou, Vassilis Psycharis, Maria Pelecanou, Ioannis Pirmettis, and Minas Papadopoulos. "Crystal structure offac-tricarbonyl(cyclohexyl isocyanide-κC)(quinoline-2-carboxylato-κ2N,O)rhenium(I)." Acta Crystallographica Section E Crystallographic Communications 72, no. 3 (February 17, 2016): 358–62. http://dx.doi.org/10.1107/s2056989016002206.
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In the title compound, [Re(C10H6NO2)(C7H11N)(CO)3], the ReIatom is coordinated by three carbonyl ligands in a facial arrangement and by the N, O and C atoms from a chelating quinaldate anion and a monodentate isocyanide ligand, respectively. The resultant C4NO coordination sphere is distorted octahedral. A lengthening of the axial Re—CO bondtransto the isocyanide ligand is indicative of thetranseffect. Individual complexes are stacked into rods parallel to [001] through displaced π–π interactions. Weak C—H...O hydrogen-bonding interactions between the rods lead to the formation of layers parallel to (010). These layers are stacked along [010] by C—H...H—C van der Waals contacts.
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Koshel, Sergiy, and Ganna Koshel. "Analysis of fourth-grade flat machines with movable close-cycle formed by the rods and two complex links." Odes’kyi Politechnichnyi Universytet. Pratsi, no. 2 (August 20, 2016): 5–10. http://dx.doi.org/10.15276/opu.2.49.2016.03.
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Bazunova, Marina V., Robert A. Mustakimov, Nadezhda V. Dmitrieva, Diana R. Dayanova, and Andrey A. Bazunov. "Study of the physical and chemical properties of materials based on polymer complexes of some water-soluble polymers." Butlerov Communications 62, no. 5 (May 31, 2020): 91–96. http://dx.doi.org/10.37952/roi-jbc-01/20-62-5-91.
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Polymer complexes based on water-soluble physiologically-neutral polymers are promising for creating biomedical materials used in targeted delivery systems of drugs, enzymes or genes, as well as for encapsulating biological substances in biomedicine. In this work, the creation of film materials based on polymer complexes has used the sodium salt of succinyl chitosan, polyvinylpyrrolidone, sodium salt of carboxymethylcellulose, polyethylene glycol. Polyvinylpyrrolidone and polyethylene glycol are characterized by unsatisfactory a film-forming and gel-forming property, which limits their application in medical practice. These shortcomings have been compensated by the introduction of polysaccharides. It has been shown that the variation in composition of the studied polymer complexes allows changing purposefully the hydrophilic-hydrophobic balance of the surface and sorption properties of polymer films based on them. The preparation of polymer complexes consisted of adding a portion of poly-N-vinylpyrrolidone or polyethylene glycol to solutions of the sodium salt of succinyl chitosan or sodium salt of carboxymethylcellulose so that the ratio of the components of the complex was equimolar. Films based on polymer complexes were prepared by the method of pouring solutions of polymer mixtures with a concentration of 1 mol/L onto a previously defatted surface of a Petri dish. The thickness of the film samples was maintained constant and equal to 0.1 mm. It was shown that the preparation of polymer complexes of the sodium salt of chitosan succinyl or the sodium salt of carboxymethyl cellulose with poly-(N-vinylpyrrolidone) or polyethylene glycol allows one to purposefully change the hydrophilic-hydrophobic balance of the surface of polymer films based on them. Also, film materials based on the studied polymer complexes have satisfactory sorption properties for water vapor. These facts suggest that systems based on polymer complexes of the sodium salt of chitosan succinyl or sodium salt of carboxymethylcellulose with poly (N-vinyl pyrrolidone) or polyethylene glycol can serve as the basis for the creation of film or gel polymer materials for medical use.
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DeRouchey, Jason, Greg F. Walker, Ernst Wagner, and Joachim O. Rädler. "Decorated Rods: A “Bottom-Up” Self-Assembly of Monomolecular DNA Complexes." Journal of Physical Chemistry B 110, no. 10 (March 2006): 4548–54. http://dx.doi.org/10.1021/jp053760a.
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Kedzierski, W., W. N. Moghrabi, A. C. Allen, M. M. Jablonski-Stiemke, S. M. Azarian, D. Bok, and G. H. Travis. "Three homologs of rds/peripherin in Xenopus laevis photoreceptors that exhibit covalent and non-covalent interactions." Journal of Cell Science 109, no. 10 (October 1, 1996): 2551–60. http://dx.doi.org/10.1242/jcs.109.10.2551.
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We have isolated and characterized three homologs of mammalian rds/peripherin from Xenopus retinae. One (xrds38) is likely the Xenopus ortholog, while the other two (xrds36 and -35) are more distant relatives. By immunocytochemical analysis of retinal sections, xrds38 is distributed in both rod and cone photoreceptors, while xrds36 and xrds35 are present in rods only. At the EM level, xrds38 is present specifically in the rims and incisures of rod and cone outer segment discs. All are N-glycosylated and form covalent dimers. Immunoprecipitation analysis showed that in rods, these three proteins interact to form heterotetrameric or higher-order complexes. The pattern of sequence conservation among the xrds proteins, mammalian rds/peripherin, and mammalian rom-1 suggest that the central portion of the intradiscal D2 loop contains the interacting structural elements.
Dissertations / Theses on the topic "Complexos de rodi"
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Gimeno, Bolaño Josep. "Hidroformilació selectiva d'amides i imides catalitzada per complexos de rodi." Doctoral thesis, Universitat Autònoma de Barcelona, 2002. http://hdl.handle.net/10803/3140.
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En aquest treball s'han abordat tres objectius, tots ells relacionats amb la reacció d'hidroformilació i en la seva aplicació a la síntesi de productes d'alt valor afegit.El primer dels objectius ha estat la síntesi de tres lligands ditioacetat quirals a partir de l'L-(-)-lactat d'etil i diols bicíclics, que en algun cas incorporaven un centre atropoisomèric, per a ser emprats en la reacció d'hidroformilació enantioselectiva catalitzada per complexos tiolat de rodi o bé en altres reaccions asimètriques. Els ditioacetats han pogut ser preparats però no de forma enantiomèricament pura, ja que s'ha observat una racemització del carboni estereogènic clàssic en la darrera de les cinc etapes previstes per la síntesi d'aquests compostos. En aquesta darrera etapa, la basicitat de l'anió tioacetat usat en la substitució nucleofílica dels productes ditosilats ha estat suficient per abstreure el protó a-carbonilic. No s'han trobat precedents d'una reacció similar amb aquest anió.
El segon objectiu del treball ha estat la hidroformilació diastereoselectiva de tres trans-N-1-propeniltartarimides homoquirals. La ruta emprada per sintetitzar-les consisteix, en primer lloc, en la condensació de l'N-al·lilamina i l'àcid L-(-)-tartàric per obtenir l'N?al·liltartarimida. L'esterificació dels grups OH d'aquesta amb els anhídrids apropiats permet obtenir les N-al·liltartarimides funcionalitzades amb grups CH3COO-, (CH3)3COO- i PhCOO-. Finalment, la isomerització d'aquestes imides permet sintetitzar les trans-N-1-propeniltartarimides. Els precedents bibliogràfics indiquen que la isomerització d'imides és una reacció complicada, ja que sovint requereix quantitats elevades de catalitzador així com condicions de reacció dràstiques. En aquest treball s'han assajat diferents complexos metàl·lics de rodi i de ruteni com a catalitzadors d'isomerització. Els millors resultats s'obtenen utilitzant el complex RuClH(CO)(PPh3)3 (1% molar). S'assoleixen conversions properes al 90% en dues hores de reacció amb una regioselectivitat en l'isòmer trans del 90%. Aquests valors representen els millors resultats reportats fins al moment en aquest tipus de reacció. La hidroformilació de les trans-N-1-propeniltartarimides sintetitzades s'ha dut a terme amb catalitzadors de rodi no quirals amb la intenció d'obtenir els aldehids de manera diastereoselectiva. Els resultats obtinguts indiquen que és la naturalesa del substrat la que controla la formació de l'alquil complex i que l'estructura del catalitzador no influeix, de forma determinant, en la selectivitat. Per altra banda, no s'han observat en cap cas excessos diastereoisomèrics superiors al 10%, fet que indica que els diferents substituents no tenen un efecte clar sobre l'estereoselectivitat de la reacció.
El tercer i darrer objectiu ha estat l'obtenció de l'N-acetil-2-pirrolina a partir de l'N-al·lilacetamida mitjançant la reacció d'hidroformilació. Aquest heterocicle nitrogenat pot usar-se com a buillding-block en la síntesi de diferents molècules amb activitat biològica, especialment alcaloides. La hidroformilació de l'N-al·lilacetamida s'ha portat a terme emprant catalitzadors de rodi i les difosfines Bisbi i Xantphos, i el difosfit tert-butil Biphephos com a co-catalitzadors. Amb el sistema Rh/Xantphos s'obtenen quimio- i regioselectivitats superiors al 90% en l'aldehid lineal o els seus derivats. La ciclació intramolecular del 2-acetamidobutanal, producte majoritari de la reacció d'hidroformilació, i la posterior deshidratació de l'alcohol resultant, permet obtenir l'N-acetil-2-pirrolina a partir de l'N?al·lilacetamida mitjançant un procés one pot amb una excel·lent economia atòmica. S'ha estudiat en profunditat la ciclació i posterior deshidratació. Així s'ha determinat que catalitzadors àcids de tipus Brönsted provoquen l'aparició de productes de doble condensació no desitjats i que el millor catalitzador per aquestes reaccions és el tamís molecular de 3 Å finament polvoritzat i assistit per una destil·lació en continu de l'azeòtrop toluè/aigua. Amb aquest mètode s'ha pogut obtenir el producte desitjat a partir de l'N?al·lilacetamida, CO, H2 i un 0.0002% de Rh amb un rendiment del 41%.
Three main goals were set at the beginning of this work, all of them related with the hydroformylation reaction and its application in the synthesis of fine chemicals.
The first goal is the synthesis of three chiral ditioacetate ligands coming from the L?(-)-ethyl lactate and bicyclic diols, that in some cases contain an atropoisomeric centre. These ligands could be used in the enantioselective hydroformylation of olefins catalysed by rhodium complexes or in other asymmetric reactions. The ditioacetates were prepared but not enantiomerically pure, because of the racemization of the "classical" estereogenic centre in the last of the five steps of the synthetic pathway designed. In this last step, the basicity of the tioacetate anion used in the nucleophilic substitution of the corresponding ditosilate intermediates was enough to abstract the a?carbonilic hydrogen. As far as we know, there is no precedent of such a reaction with this anion.
The second goal of this work is the diastereoselective hydroformylation of three homochiral trans-N-1-propenyltartarimides. The synthetic pathway consists, first of all, in the condensation of the N-allylamine and the L-(-)-tartaric acid to obtain the N?allyltartarimide. The esterification of the OH groups of this imide with the suitable anhydrides allows the synthesis of the corresponding N-allyltartarimides functionalised with the CH3COO-, (CH3)3COO- and PhCOO- groups. Finally, the isomerization of these imides leads to the trans-N-1-propenyltartarimides. The literature indicates that imide isomerization is a difficult reaction, usually it requires high levels of catalyst and heavy reaction conditions. In this work a number of rhodium and ruthenium complexes has been tested as catalysts. The best result were found using RuClH(CO)(PPh3)3 (1% molar). It is possible to reach yields up to 90% in two hours of reaction with a regioselectivity in the trans isomer up to 90%. As far as we know that results represent the best ones ever reported in such a reaction. The hydroformylation of the trans-N-1-propenyltartarimides has been done using non-chiral rhodium complexes as catalysts with the aim of obtaining the aldehydes in a diastereoselective way. The results obtained indicate that the nature of the substrate is controlling the alkyl complex formation during hydroformylation and that there is not any effect of the catalyst in the selectivity. Moreover, diastereomeric excess in the aldehydes formation does not exceed 10%, which indicates that there is not a clear effect of the substrate nature in the stereoselectivity of the reaction.
The third and last goal of this work is the synthesis of N-acetyl-2-pyrroline through the hydroformylation of N-allylacetamide. This heterocycle containing nitrogen can be used as building-block for the synthesis of a number of molecules with biological activity, specially alkaloids. The hydroformylation of N-allylacetamide was attempted using rhodium catalysts and diphosphines (Bisbi and Xantphos) or diphosphites (tert-butil Biphephos) as co-catalysts. With the catalytic system Rh/Xantphos, chimio- and regioselectivities exceeding 90% in the linear aldehyde or their derivatives are obtained. 2-acetamidobutanal is the major product of the hydroformylation reaction, it cycles in an intramolecular way to obtain the corresponding alcohol, the dehydration of which leads to the N-acetyl-2-pyrroline in a one-pot process with an excellent atomic economy. The cycle formation and the dehydration reaction of the alcohol has been deeply investigated. It has been found that Brönsted catalysts promote double condensation products formation which are undesirable. After a number of tests the best catalyst for the one-pot reaction referred above is 3 Å molecular sieves finely powdered and assisted by a continuous distillation of the toluene/water azeotrop. According to this method it is possible to obtain N-acetyl-2-pyrroline from N-allylacetamide, CO, H2 and a 0.0002% of rhodium with a global yield of 41%.
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Ruiz, Morillas Nuria. "Complexos de rodi amb lligands nitrigen i sofre dadors. Estudi de l-activitat catalitica." Doctoral thesis, Universitat Rovira i Virgili, 1993. http://hdl.handle.net/10803/8976.
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Esquius, i. Calvés Glòria. "Síntesi i caracterització de complexos de Rh(I) i Ru(II) amb lligands amino- i fosfinoalquilpirazole." Doctoral thesis, Universitat Autònoma de Barcelona, 2002. http://hdl.handle.net/10803/3137.
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Els nous lligands 3,5-dimetil-4-(etilamino)metilpirazole (HL1) i 3,5-dimetil-4-(isopropilamino)metilpirazole (HL2), són capaços de coordinar a Rh(I) de forma exodidentada, i formar espècies "zwitterióniques" pirazolat-amoni. Les estructures cristal·lines dels complexos dinuclears [Rh(HL1)(COD)]2Cl2 i [Rh(HL2)(COD)]2Cl2 confirmen que els metalls presenten una geometria pla-quadrada, coordinant-se al lligand COD i a dues molècules de lligand pirazolat pont. Per reacció de complexació dels lligands prèviament desprotonats (L1 i L2) amb Rh(I) s'obtenen els complexos neutres [Rh(L1)(COD)]2 i [Rh(L2)(COD)]2. Tant els complexos iònics com els neutres, reaccionen amb monòxid de carboni per donar els complexos [Rh(HL1)(CO)2]2Cl2, [Rh(HL2)(CO)2]2Cl2, [Rh(L1)(CO)2]2 i [Rh(L2)(CO)2]2. Tots els complexos presenten una solubilitat notable en dissolvents polars i, fins i tot en aigua, mentre que són insolubles en hidrocarburs saturats.1, 2Tant els lligands 1-aminoalquilpirazole potencialment didentats (NN') com els potencialment tridentats (NN'N), reaccionen amb el dímer [RhCl(COD)]2 per donar lloc a les espècies [Rh2Cl2(L)(COD)2] (L=NN' o NN'N). Les dades de RMN junt amb les de conductivitat són coherents amb l'existència d'un equilibri en solució entre la forma iònica [Rh(L)(COD)]+ [RhCl2(COD)]- i una forma neutra [Rh(COD)Cl][m-(L)][Rh(COD)Cl]. Els espectres de masses d'electroesprai confirmen la presència de les espècies iòniques [Rh(L)(COD)]+[RhCl2(COD)]- en solució.3
Per reacció del lligand bis[(3,5-dimetil-1-pirazolil)metil]etilamina (1) amb [Rh(COD)(THF)2][BF4] s'obté el complex [Rh(COD)(1)][BF4], que per posterior tractament amb CO, es transforma en els complexos [Rh(CO)2(1)][BF4] i [Rh(CO)(1)][BF4]. Tant les dades estructurals obtingudes per difracció de Raigs X, com les de RMN de tots aquests compostos, donen evidència de la flexibilitat del lligand (1) que adapta la seva forma de coordinació k2 o k3 i la seva configuració fac o mer a la situació electrònica i estèrica al voltant de l'àtom de Rh(I).4
La reacció del lligand 1-[(P-difenil)-2-fosfinoetil]-3,5-dimetilpirazole (2) i del lligand anàleg N-N' 1-[(N-etil)-2-aminoetil]-3,5-dimetilpirazole (1) amb [Rh(COD)(THF)2][BF4], dóna lloc als complexos [Rh(COD)(2)][BF4] (4) i [Rh(COD)(1)][BF4] (3). La substitució del lligand COD en els complexos 3 i 4, per CO dóna lloc als complexos [Rh(CO)2(1)][BF4] (5) i [Rh(CO)2(2)][BF4] (6). La reacció del complex [Rh(COD)(THF)2][BF4] en proporció M/L 1/2 amb el lligand 2 N-P dóna lloc al complex [Rh(2)2][BF4] (7) que presenta les dues molècules del lligand en disposició cis en una geometria pla-quadrada entorn del Rh(I). Bombollejant CO en una solució del complex (7), s'obté el complex [Rh(CO)(2)2][BF4] (8) que consisteix en un àtom de Rh(I) amb un entorn pla-quadrat amb els dos àtoms de fòsfor en disposició trans, on un dels lligands 2 està coordinat de forma didentada, mentre que l'altre ho està de forma monodentada.5
El lligand 1-[(P-difenil)-2-fosfinoetil]-3,5-dimetilpirazole (1), desplaça la trifenilfosfina del complex [RuCl2(PPh3)3] per formar els complexos [RuCl2(PPh3)(1)] (2) o [RuCl2(1)2] (3), depenent de si es treballa en proporció M/L 1/1 o 1/2 respectivament. Quan es porta a terme la reacció del complex 2 de 16e- amb acetilens, aquest descomposa. Mentre que quan es porta a terme la mateixa reacció però amb el complex 3 de 18e-, s'obtenen els metal·locumulens [RuCl(1)2(C=C=CPhCH3)][BF4] (4), [RuCl(1)2(C=C=CPh2)][BF4] (5) i [RuCl(1)2(C=CHPh)][PF6] (6). De la resolució de l'estructura cristal·lina per difracció de Raigs X del complex 5, s'obté una cel·la unitat que conté dos enantiòmers.6
1. Esquius, G.; Pons, J.; Yáñez, R.; Ros, J.; Solans, X.; Font-Bardía, M. J. Organomet. Chem. 2000, 605, 226.
2. Esquius, G.; Pons, J.; Yáñez, R.; Ros, J.; Solans, X.; Font-Bardia, M. Acta Cryst. 2002, C58, m133.
3. Esquius, G.; Pons, J.; Yáñez, R.; Ros, J. J. Organomet. Chem. 2001, 619, 14.
4. Mathieu, R.; Esquius, G.; Lugan, N.; Pons, J.; Ros, J. Eur. J. Inorg. Chem. 2001, 2683.
5. Esquius, G.; Pons, J.; Yáñez, R.; Ros, J.; Mathieu, R.; Donnadieu, B.; Lugan, N. Eur. J. Inorg. Chem. 2002, a la impremta.
6. Esquius, G.; Pons, J.; Yáñez, R.; Ros, J.; Mathieu, R.; Donnadieu, B.; Lugan, N. J. Chem. Soc., Dalton Trans. En preparació.
The new ligands 3,5-dimethyl-4-(ethylamino)methylpyrazole (HL1) and 3,5-dimetil-4-(isopropylamino)methylpyrazole (HL2), are able to coordinate to Rh(I) in a exodidentate mode, and to form "zwitterionic" species pyrazolate-ammonium. The crystal structures of dinuclear complexes [Rh(HL1)(COD)]2Cl2 and [Rh(HL2)(COD)]2Cl2 confirm the square-planar geometry of Rh(I) atoms, which are coordinated to a chelated COD ligand and to two pyrazolate ligands. The reaction of the ligands previously deprotonated (L1 and L2) with Rh(I) results in neutral complexes [Rh(L1)(COD)]2 and [Rh(L2)(COD)]2. The ionic complexes as well as the neutral ones, react with carbon monoxide to give the complexes [Rh(HL1)(CO)2]2Cl2, [Rh(HL2)(CO)2]2Cl2, [Rh(L1)(CO)2]2 and [Rh(L2)(CO)2]2. All the complexes synthesized are soluble in polar solvents such as water but insoluble in saturate hidrocarbons.1, 2
New didentate (NN') and tridentate (NN'N) 1-aminoalkylpyrazoles react with [RhCl(COD)]2 to give [Rh2Cl2(L)(COD)2] (L=NN' or NN'N) complexes. The NMR spectra and molar conductances of these complexes suggested the presence of an equilibrium in solution between 1:1 electrolyte species [Rh(L)(COD)]+ [RhCl2(COD)]- and a neutral molecular form [Rh(COD)Cl][m-(L)][Rh(COD)Cl]. Electrospray mass spectrometry study confirmed the presence of ionic species [Rh(L)(COD)]+[RhCl2(COD)]-.3
The reaction of bis[(3,5-dimethyl-1-pyrazolyl)methyl]ethylamine (1) ligand with [Rh(COD)(THF)2][BF4] results in [Rh(COD)(1)][BF4] complex, which was treated with CO to obtain [Rh(CO)2(1)][BF4] and [Rh(CO)(1)][BF4] complexes. The NMR spectra and the structures of these complexes reveal that 1 is a very flexible ligand which adapts its bonding mode (k2 or k3) and its configuration (fac or mer) to various electronic and steric situations around Rh(I).4
The reaction of 1-[(P-diphenyl)-2-phosphinoethyl]-3,5-dimethylpyrazole (2) and the related N-N' didentade ligand 1-[(N-ethyl)-2-aminoethyl]-3,5-dimethylpyrazole (1) with [Rh(COD)(THF)2][BF4], leads to the complexes [Rh(COD)(2)][BF4] (4) and [Rh(COD)(1)][BF4] (3). The 1,5-COD ligand in complexes 3 and 4 can easily be displaced by carbon monoxide leading to the complexes [Rh(CO)2(1)][BF4] (5) and [Rh(CO)2(2)][BF4] (6). The reaction of two equivalents of 2 with complex [Rh(COD)(THF)2][BF4] leads to [Rh(2)2][BF4] (7) in which the two molecules of 2 ligand are in cis position. Complex (7) reacts with CO to give complex [Rh(CO)(2)2][BF4] (8) which presents a square-planar structure with the two phosphorus atoms in trans position and only one of the two ligands 2 is k2 coordinated, the second one being k1 coordinated by the phosphorus atom to rhodium.5
The didentate ligand 1-[(P-diphenyl)-2-phosphinoethyl]-3,5-dimethylpyrazole (1) forms, depending on the stoichiometry of reactants, the [RuCl2(PPh3)(1)] (2) or [RuCl2(1)2] (3) complexes by reaction with [RuCl2(PPh3)3]. Complex 2 decomposes by reaction with acetylene derivates. Reaction of complex 3 with terminal alkynes leads to the formation of new cationic metallacumulenes: [RuCl(1)2(C=C=CPhCH3)][BF4] (4), [RuCl(1)2(C=C=CPh2)][BF4] (5) and [RuCl(1)2(C=CHPh)][PF6] (6). The crystal structure of complex 5 consists of two independent ion pairs per unit cell, whose cation corresponds to two enantiomers.6
1. Esquius, G.; Pons, J.; Yáñez, R.; Ros, J.; Solans, X.; Font-Bardía, M. J. Organomet. Chem. 2000, 605, 226.
2. Esquius, G.; Pons, J.; Yáñez, R.; Ros, J.; Solans, X.; Font-Bardia, M. Acta Cryst. 2002, C58, m133.
3. Esquius, G.; Pons, J.; Yáñez, R.; Ros, J. J. Organomet. Chem. 2001, 619, 14.
4. Mathieu, R.; Esquius, G.; Lugan, N.; Pons, J.; Ros, J. Eur. J. Inorg. Chem. 2001, 2683.
5. Esquius, G.; Pons, J.; Yáñez, R.; Ros, J.; Mathieu, R.; Donnadieu, B.; Lugan, N. Eur. J. Inorg. Chem. 2002, in press.
6. Esquius, G.; Pons, J.; Yáñez, R.; Ros, J.; Mathieu, R.; Donnadieu, B.; Lugan, N. J. Chem. Soc., Dalton Trans. In preparation.
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Alansawi, Deeb. "Rigid-Rod Structured Homobimetallic Complexes." Doctoral thesis, Universitätsbibliothek Chemnitz, 2005. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200500344.
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The synthesis and reaction chemistry of trans-(PPh3)2Pd(C6H4-4-I)(X) (X = I, OTf) is discussed. Treatment of trans- (PPh3)2Pd(C6H4- 4-I)(OTf) with bidentate Lewis-bases (N)N), such as pz, bipy, C5H4N-4-CN, (C6H4-4-CN)2 or C6H4-1,4-CN produces, depending on N)N, mono- or bimetallic species of type [trans- (PPh3)2Pd(C6H4-4-I)(N)N)]+ or [trans-(Ph3P)2(C6H4- 4-I)Pd N)N Pd- (PPh3)2(C6H4-4-I)]2+. These new complexes rearrange in the solution to give [trans-[(Ph3P)2Pd(C6H4-4-PPh3)(N)N)]2+ (N)N = C4H4N2, C5H4N-4-CN, NaC-4-C5H4N) and [trans-[(Ph3P)2(C6H4-4-PPh3)- Pd N)N Pd(PPh3)2(C6H4-4-PPh3)]4+ (N)N = C6H4-1,4-(CN)2, (C6H4-4- CN)2) along with {[(Ph3P)2(Ph3P-4-C6H4)Pd -(µ-I)]2}2+. The mechanism is elucidated. The latter species are rigid-rod structured. The preparation of mono- and homo-bimetallic palladium complexes of type [(Me(O)CS-4-C6H4)(PPh3)2Pd -(N)N)]+ and {[(Me- (O)CS-4-C6H4)(PPh3)2Pd]2(N)N)} 2+ (N)N = pz, bipy, C5H4N-4-CN, (C6H4-4-CN)2, C6H4-1,4-CN) is reported. The formation of the mono- or bimetallic species depends on the size of the Lewis bases N)N. The use of these molecules as molecular wire is discussed. The synthesis of homo-bimetallic palladium molecular wire complexes of type {[(Me(O)CS-4-C6H4-C6H4)(PPh3)2Pd]2(N)N)}2+ is described. The structural aspects of these complexes in the solid-state by single X-ray crystallography is discussed. The synthesis, characterization and electrochemical properties of a new series of homo-bimetallic palladium and platinum complexes of type [Me(O)CS-NCN-M]2(N)N) (NCN = [C6H2(CH2NMe2)2- 2,6)]-) is described. The effect of the para-substituent of the functionalized thio-acetyl NCN ligand on the electrochemical properties of the incorporated platinum center is discussed. The selective synthesis of acetylene and acyl-thiol endcapped heterobimetallic organometallic pi-tweezer of type {[Ti](µ-sigma,pi-CCR)2}CuS-C6H4-4-R ([Ti] = (eta5-C5H4SiMe3)2Ti; R = SiMe3; R = CCH,R = SC(O)Me) succeeds by the reaction of {[Ti](CCR)2}CuCH3 with equimolar amounts of Me(O)CSC6H4-4-CCH or the dithiol C6H4-1,4-(SC(O)Me)2. Binuclear (µ-RSe)(µ sigma,pi CCPh)Fe2(CO)6 can be prepared by treatment of RSe-CCPh (R = Et, nBu, Ph, 2,4,6-Me3C6H2) with Fe2(CO)9 in tetrahydrofuran at room temperature. In solution two isomers exist, depending on the position of the lone-pair of electrons present at selenium (axial or equatorial, respectively). Nucleophilic addition of P(OiC3H7)3 to (µ-RSe)- (µ -sigma,pi CCPh)Fe2(CO)6 affords vinylidene- and dimetallacylobutene- bridged complexes Fe2(CO)6(µ-Se(2,4,6-Me3C6H2)(µ-eta1C=C(Ph)- (P(OiC3H7)3) and [Fe2(CO)6(µ-Se(2,4,6-Me3C6H2)-(µ -eta1:eta1(Ph)C=C- {P(OiC3H7)3). The isolated complexes were characterized by multinuclear NMR (1H, 13C{1H}, and 31P{1H}, elemental analysis, FT-IR, and single x-ray crystallographyEin Ziel der Arbeit war die Synthese von trans-(PPh3)2Pd(C6H4-4-I)(X) (X = I, OTf) und Untersuchungen zu dessen Reaktionsverhalten. Die Zugabe von zweizähnigen Lewis-Basen (N)N), wie z.B. pz, pz, bipy, C5H4N-4-CN, (C6H4-4-CN)2 oder C6H4-1,4-CN ergibt, abhängig von (N)N), mono- oder bimetallische Spezies vom Typ [trans-(PPh3)2Pd(C6H4-4-I)(N)N)]+ oder [trans-(Ph3P)2(C6H4-4-I)Pd N)N Pd-(PPh3)2(C6H4-4-I)]2+. Diese in Lösung instabilen Komplexe reagieren weiter zu [trans-[(Ph3P)2Pd(C6H4-4-PPh3)(N)N)]2+ (N)N = C4H4N2, C5H4N- 4-CN, NC-4-C5H4N) oder [trans-[(Ph3P)2(C6H4-4-PPh3)Pd N)N Pd(PPh3)2-(C6H4-4- PPh3)]4+ (N)N = C6H4-1,4-(CN)2, (C6H4-4-CN)2) zusammen mit {[(Ph3P)2(Ph3P-4- C6H4)Pd(µ-I)]2}2+. Der Mechanismus dieser Reaktionsfolge wurde aufgeklärt. Diese Komplexe besitzen eine starre, lineare Struktur, welche unter anderem mittels Röntgeneinkristallstrukturanalyse ermittelt wurde. Weiterhin wird über die Darstellung von mono- und homobimetallischen Palladium-Komplexen vom Typ [(Me(O)CS-4-C6H4)(PPh3)2Pd(N)N)]+ und {[(Me- (O)CS-4-C6H4)(PPh3)2Pd]2(N)N)}2+ (N)N = pz, bipy, C5H4N-4-CN, (C6H4-4-CN)2, C6H4-1,4-CN) berichtet. Die Bildung von homo- oder bimetallischen Spezies hängt von der Größe der Lewis-Base N)N ab. Die Anwendung dieser Moleküle als molekulare Drähte wird, zusammen mit der Festkörperstruktur zweier dieser Komplexe, diskutiert. Die Synthese von homobimetallischen Pd Komplexen vom Typ {[(Me(O)CS-4- C6H4-C6H4)(PPh3)2Pd]2(N)N)}2+ (molekulare Drähte) wird beschrieben. Die strukturellen Aspekte dieser Komplexe im festen Zustand werden diskutiert Die Synthese, Charakterisierung und elektrochemischen Eigenschaften einer neuen Serie von homobimetallischen Pd und Pt Komplexen vom Typ [Me(O)CSNCN- M]2(N)N) (NCN = [C6H2(CH2NMe2)2-2,6)]-) wird beschrieben. Der Effekt des para-Substituenten der funktionalisierten Thioacetyl-NCN Liganden auf die elektrochemischen Eigenschaften des komplexierten Pt wird diskutiert. Die selektive Synthese von Alkinyl- und Thioacetyl-funkionalisierten heterobimetallischen metallorganischen pi-Pinzetten-Komplexen vom Typ {[Ti](µ-sigma,pi-CCR)2}CuS-C6H4-4-CCH und {[Ti](µ-sigma,pi-CCR)2}CuS-C6H4-4-SC(O)Me ([Ti] = (eta5-C5H4SiMe3)2Ti; R = SiMe3, R = tBu) erfolgt durch die Reaktion von {[Ti](CCR)2}CuCH3 (R = SiMe3, R = tBu) mit äquimolaren Mengen an Me(O)CS-1- C6H4-4-CCH oder des Dithiols C6H4-1,4-(SC(O)Me)2. Im Vorgang dieser Reaktion wird Aceton gebildet. Zweikernige (µ-RSe)(µ sigma,pi CCPh)Fe2(CO)6 Komplexe können durch die Umsetzung von RSe-CCPh (R = Et, nBu, Ph, 2,4,6-Me3C6H2) mit Fe2(CO)9 in Tetrahydrofuran bei 20 °C dargestellt werden. In Lösung liegen, in Abhängigkeit von der Position des freien Elektronenpaares am Selen (axial oder äquatorial), zwei Isomere vor. Addition von P(OiC3H7)3 zu (µ-RSe)(µ sigma,pi CCPh)Fe2-(CO)6 ergibt Vinyliden- Fe2(CO)6(µ-Se(2,4,6-Me3C6H2)-(µ-eta1 C=C-(Ph)(P(OiC3H7)3) und Dimetallacyclobuten- verbrückte Komplexe der Art [Fe2(CO)6(µ-Se(2,4,6-Me3C6H2)-(µ-eta1:eta1- (Ph)C=C{P(OiC3H7)3). Die isolierten Komplexe wurden durch die Elementaranalyse, spektroskopisch (1H, 13C{1H}, 31P{1H} NMR; IR) und die Röntgeneinkristallstrukturanalyse charakterisiert
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Campos, Jose Daniel Ribeiro de. "Preparação, caracterização e propriedades cataliticas e complexos de rodio ancorados em silicas funcionalizadas." [s.n.], 1999. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249145.
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Orientador: Regina BuffonDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
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Mestrado
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Ballisai, Antonio. "Synthesis of rigid-rod metal-alkynyl complexes." Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433302.
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Martínez, Lombardía Alberto. "Heterogenized n-heterocyclic carbene metal complexes for selective catalysis." Doctoral thesis, Universitat Rovira i Virgili, 2016. http://hdl.handle.net/10803/386577.
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La present tesi doctoral està adreçada al desenvolupament de catalitzadors que permetin dur a terme processos sintètics de manera més eficient i sostenible. Es presenten dues noves famílies de catalitzadors suportats, ambdues pertanyents al grup de complexos organometàl·lics moleculars immobilitzats sobre un suport sòlid. La primera família inclou complexos de Pd amb lligands carbè N-heterocíclic monodentats de gran impediment estèric, immobilitzats sobre òxids inorgànics, com ara sílicas, alúmina o òxid de titani. Aquesta família de catalitzadors es va aplicar en dos tipus de reaccions: i) reaccions d'acoblament C-C i ii) semireducción d'alquins. Entre les reaccions d'acoblament esmentades, els complexos de [Pd (NHC)] immobilitzats es van aplicar a les reaccions de Suzuki, Heck i Sonogashira, i es van avaluar en base a la seva activitat, selectivitat i reciclabilitat. A més, en el cas de les reaccions de Suzuki i Sonogashira, aquests catalitzadors també es van aplicar en condicions de flux continu. L'aplicació d'aquesta família de catalitzadors en la semireducció selectiva d'alquins es va dur a terme utilitzant dues metodologies diferents: utilitzant hidrogen molecular, o bé utilitzant el sistema trietilamina / àcid fòrmic com donador de H (condicions de transferència d'hidrogen).
La segona família de catalitzadors suportats contempla complexos de Rh (I) estabilitzats amb lligands bidentats de tipus carbé N-heterocíclic, amb quiralitat axial, i funcionalitzats amb un grup piré. La immobilització d'aquests complexos de Rh sobre la superfície de nanotubs de carboni "multi-walled" va tenir lloc mitjançant interaccions de tipus "pi-pi stacking" entre la superfície dels nanotubs i el grup piré present en el lligand. Finalment, es presenten els resultats obtinguts en l'aplicació d'aquests complexos de Rh en diversos processos catalítics.La presente tesis doctoral se centra en el desarrollo de catalizadores que permitan llevar a cabo procesos sintéticos de manera más eficiente y sostenible. Se presentan dos nuevas familias de catalizadores soportados, ambas pertenecientes al grupo de complejos organometálicos moleculares inmovilizados sobre un soporte sólido. La primera familia incluye complejos de Pd con ligandos carbeno N-heterocíclico monodentados de gran impedimento estérico, inmovilizados sobre óxidos inorgánicos, como sílicas, alúmina u òxido de titanio. Esta familia de catalizadores se aplicó en dos tipos de reacciones: i) reacciones de acoplamiento C-C y ii) semireducción de alquinos. Entre las reacciones de acoplamiento mencionadas, los complejos de [Pd(NHC)] inmovilizados se aplicaron en las reacciones de Suzuki, Heck y Sonogashira, y se evaluaron en base a su actividad, selectividad y reciclabilidad. Además, en el caso de las reacciones de Suzuki y Sonogashira, estos catalizadores también se aplicaron en condiciones de flujo continuo. La aplicación de esta familia de catalizadores en la semireducción selectiva de alquinos se llevó a cabo utilizando dos metodologías diferentes: utilizando hidrógeno molecular, o bien utilizando el sistema trietilamina/ácido fórmico como dador de H (condiciones de transferencia de hidrógeno). La segunda familia de catalizadores soportados contempla complejos de Rh(I) estabilizados con ligandos bidentados de tipo carbeno N-heterocíclico, con quiralidad axial, y funcionalizados con un grupo pireno. La inmovilización de estos complejos de Rh sobre la superficie de nanotubos de carbono "multi-walled" tuvo lugar mediante interacciones de tipo "pi-pi stacking" entre la superficie de los nanotubos y el grupo pireno presente en el ligando. Finalmente, se presentan los resultados obtenidos en la aplicación de estos complejos de Rh en varios procesos catalíticos.
The present PhD thesis aims at contributing to the development of more efficient and sustainable synthetic processes through catalysis. In this regard, two families of new solid-supported catalysts are presented. Both families belong to the group of molecularly defined organometallic complexes immobilized onto a solid support. The first family includes Pd complexes of sterically hindered monodentate N-Heterocylic Carbene ligands supported onto inorganic oxide materials, namely silicas, alumina and titania. This family of catalysts was applied in two types of reactions: i) C-C cross-couplings and ii) semireduction of alkynes. Among cross-coupling reactions, the supported [Pd(NHC)] complexes could be applied in Suzuki, Heck and Sonogashira couplings and their performance was assessed in terms of activity, selectivity and reusability. For the Suzuki and Sonogashira couplings, the catalysts were also appied under continuous flow conditions. The application of this family of catalysts in the selective reduction of alkynes was carried out following two different methodologies: using hydrogen gas, or using triethylamine/formic acid as the H-donor system (transfer hydrogenation conditions). The second family of solid-supported catalysts features Rh(I) complexes bearing axially chiral bidentate N-Heterocyclic carbene ligands functionalized with a pyrene moiety. Immobilization of these Rh complexes onto the surface of multi-walled carbon nanotubes was achieved by means of "pi-pi stacking interactions" between the surface of the nanotubes and the pyrene moiety present in the ligand. Results obtained from the application of these complexes as catalysts in various reactions are presented.
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Pederzolli, Fernanda Rosi Soares. "“Heterogeneização de complexos à base de ródio com ligantes ciclopentadienila : estudo em reações de hidrogenação catalítica”." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/181400.
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Os catalisadores imobilizados foram preparados misturando-se o ligante Cp’, [C5Me4(n-propyl-Si(OEt)3)], com RhCl3.xH2O e, em seguida, por reação com sílica Aerosil 200 (sistema A) ou por copolimerização com TEOS (sistema B). Ambos os sistemas foram aplicados na hidrogenação de olefinas e mostraram-se altamente ativos e robustos, permitindo um grande número de reciclagens (NR = 1,0 ×105, sistema A e 2,0 ×104, sistema B). As técnicas de caracterização (IV-DRIFTS, 13C-CPMAS, e MET) indicaram que as espécies ativas eram de natureza molecular. Os experimentos de deuteração mostraram a presença de complexos tetra-hapto-Cp’-Rh na superfície da sílica durante os testes catalíticos. O sistema Cp’/ Rh+3 em fase homogênea também se mostrou ativo na hidrogenação de olefinas, permitindo 25 recargas de substrato (NR = 1,2 ×104). Entretanto, os espectros de RMN (1H and 13C) em fase líquida revelaram-se complexos, em desacordo com o que seria esperado para o dímero [Rh(η5-Cp(Me)4(n-propyl)- Si(OR)3)Cl(μ-Cl)]2. Os espectros no IV em estado sólido mostraram bandas que indicaram a formação de ligações siloxano. Essas informações, adicionadas à observação de sólidos de cor marrom, tanto na etapa de síntese quanto após as reações de catálise, indicaram que os grupos alcoxila do ligante sofreram condensações, que podem ter sido promovidas tanto por ácidos de Lewis (Rh+3) quanto por ácido de Arrhenius (HCl proveniente do RhCl3.xH2O).Immobilized catalysts were prepared by mixing the ligand Cp’, [C5Me4(n-propyl- Si(OEt)3)], with RhCl3.xH2O for subsequent reaction with silica Aerosil 200 (system A) or by copolymerization with TEOS (system B). Both systems were applied on olefin hydrogenation, showing high activity and robustness, allowing for many recycles (TON = 1.0 ×105 for system A and 2.0 ×104 for system B). The characterization techniques (IRDRIFTS, 13C-CPMAS, and TEM) suggest a molecular nature for catalytic species. According to the deuteration experiment, a tetra-hapto-Cp’-Rh would be formed on the surface during the catalytic runs. Homogeneously, the Cp’/ Rh+3 system proved also to be active on 1-hexene and 1,7-octadiene hydrogenation, allowing for 25 recharges of substrate (TON = 1.2 x 104). However, NMR techniques (1H and 13C) in liquid state (DMSO-d6) showed complex spectra in discordance of a simple molecular structure anticipated for the dimer [Rh(η5- Cp(Me)4(n-propyl)-Si(OR)3)Cl(μ-Cl)]2. Infrared spectroscopy in solid state reveals bands that would be ascribed to siloxanes bonds formation. This information, together with the observation of brown solids either during the syntheses or after catalysis reaction, indicated that the ligand has polymerized, which may occured by the assistance of acids (Lewis acid, Rh+3 and Arrhenius acid, HCl evolved from RhCl3.xH2O).
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Torrent, i. Palomeras Anna. "Síntesi de nous macrocicles nitrogenats poliinsaturats. Estudis de coordinació i reactivitat." Doctoral thesis, Universitat de Girona, 2007. http://hdl.handle.net/10803/8042.
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La síntesi i caracterització estructural d'un nou tipus de macrocicles nitrogenats de 15, 20 i 25 membres, els quals contenen triples i dobles enllaços i diferents unitats aríliques a la seva estructura, ha estat estudiada. S'han preparat els complexos de pal·ladi(0) dels corresponents macrocicles poliinsaturats de 15 membres, els quals són estables a l'aire i a la humitat i en alguns casos presenten quiralitat. La seva caracterització completa s'ha portat a terme mitjançant RMN i difracció de raigs-X. S'ha estudiat també la reacció de cicloisomerització d'aquests macrocicles emprant diferents catalitzadors basats en metalls de transició, observant-se que el catalitzador de Wilkinson, de rodi(I), és el que ha donat més bons resultats. Finalment, s'ha realitzat una introducció a l'estudi del mecanisme d'aquest tipus de reaccions mitjançant ESI-MS, així com també un estudi inicial de la reacció de cicloisomerització enantioselectiva.The synthesis and structural analysis of a new type of 15-, 20- and 25-membered nitrogen-containing polyunsaturated macrocycles has been carried out. Palladium(0) complexes of 15-membered polyunsaturated azamacrocycles, which are air and moisture stable and in some cases present chirality, has been prepared and fully caracterized by means of NMR spectroscopy and X-ray diffraction. The cycloisomerization reaction of these macrocycles using different catalysts based in different transition metals has been studied. It was observed that Wilkinson's catalyst (rhodium(I) catalyst) gave the best results. A brief look at the mechanism of cyclotrimerization reaction by means of ESI-MS has been carried out. Finally, an introduction in the study of the enantioselective cycloisomerization reaction of these macrocycles has been done.
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Peñafiel, Andrés Itziar. "Derivados carbocíclicos de litio y heterocíclicos de paladio y rodio." Doctoral thesis, Universidad de Alicante, 2012. http://hdl.handle.net/10045/24160.
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En la presente memoria se describe el estudio sobre la preparación y reactividad de derivados carbocíclicos de litio, y la preparación y reactividad de derivados de carbenos N-heterocíclicos de paladio y de rodio. En el primer capítulo se estudia la reacción de litiación del clorometilciclopropano y del bromometilciclobutano empleando litio metálico y una cantidad subestequiométrica de un areno, y la posterior reacción de los intermedios de litio generados con distintos compuestos carbonílicos. El uso de DTBB (4,4’-di-terc-butilbifenilo) en THF a –78 oC y en presencia del electrófilo (condiciones de reacción tipo Barbier) dio lugar, tras hidrólisis, a los correspondientes cicloalquilmetilalcanoles. Por el contrario, llevando a cabo el proceso de litiación con naftaleno en dietil éter a 0 ó 25 oC, el intermedio de litio sufre reordenamiento hacia el derivado homoalil-litio o bishomoalil-litio. La posterior reacción con compuestos carbonílicos permite la preparación de alcoholes insaturados. En el segundo capítulo se estudia en primer lugar la preparación de sales de imidazolio funcionalizadas con un grupo hidroxilo, por apertura de epóxidos con imidazol y posterior reacción con haluros de alquilo. A continuación, estas sales se han empleado en la preparación de complejos metálicos de paladio y rodio con un ligando carbeno N-heterocíclico. Los complejos, bien definidos, biscarbénico de paladio [(NHC)2PdCl2] y monocarbénico de rodio [(NHC)Rh(COD)Cl] han sido preparados por metalación directa empleando precursores básicos tanto de paladio como de rodio. Finalmente, se ha estudiado la actividad catalítica de estos complejos en diferentes procesos. El complejo de paladio se ha empleado en la reacción de acoplamiento de Hiyama, en ausencia de fluoruros y por irradicación en microondas, de diferentes (trialcoxi)arilsilanos con bromuros y cloruros de arilo. También se estudio la reacción de acoplamiento de Heck-Matsuda, catalizada por NHC-Pd, de diferentes tetrafluoroboratos de bencenodiazonio con acrilatos, acrilamida, estireno y ciclohexeno. Por otra parte, el complejo de NHC-Rh se ha mostrado activo en la reacción de adición conjugada de ácidos arilborónicos a cetonas α,β-insaturadas.
Books on the topic "Complexos de rodi"
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Roci o C arceles Morena. Manual completo de pilates suelo por Roci o Ca rceles. Badalona: Editorial Paidotribo, 2010.
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Vallejo Maldonado, Pablo Ramon, and Nikolay Chaynov. Kinematics and dynamics of automobile piston engines. ru: INFRA-M Academic Publishing LLC., 2019. http://dx.doi.org/10.12737/989072.
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The fundamentals of kinematics and dynamics of transport piston internal combustion engines made using different layout schemes are presented. Along with the traditional in-line, V-shaped, including oppositional, arrangement of cylinders, schemes with "staggered" arrangement of cylinders in the block at the displaced connecting rod necks of the crankshaft of the engine are considered. The kinematics of the coaxial crank mechanism is considered in detail. The questions of dynamics with reduction of calculated dependences of forces, moments, a choice of a rational order of work of cylinders in relation to the considered kinematic schemes are in detail stated. Considerable attention is paid to the unevenness of the crankshaft rotation speed and engine balancing. The loads on the main and connecting rod bearings of the crankshaft, the knowledge of which is necessary in determining the bearing capacity of bearing units, are also considered.
Meets the requirements of the Federal state educational standards of higher education of the last generation.
For students of higher educational institutions studying in the direction of training 23.03.03 "Operation of transport and technological machines and complexes" and related areas.
Book chapters on the topic "Complexos de rodi"
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Higashihara, Tomoya, and Mitsuru Ueda. "Block Copolymers Containing Rod Segments." In Complex Macromolecular Architectures, 395–429. Singapore: John Wiley & Sons (Asia) Pte Ltd, 2011. http://dx.doi.org/10.1002/9780470825150.ch13.
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Yam, Vivian Wing-Wah, and Keith Man-Chung Wong. "Luminescent Molecular Rods — Transition-Metal Alkynyl Complexes." In Molecular Wires and Electronics, 1–32. Berlin, Heidelberg: Springer Berlin Heidelberg, 2005. http://dx.doi.org/10.1007/b136069.
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Kuo, Chi-Ching, Cheng-Liang Liu, and Wen-Chang Chen. "Morphologies and Photophysical Properties of Conjugated Rod-Coil Block Copolymers." In Complex Macromolecular Architectures, 593–622. Singapore: John Wiley & Sons (Asia) Pte Ltd, 2011. http://dx.doi.org/10.1002/9780470825150.ch19.
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Elkaranshawy, Hesham A., and Nasser S. Bajaba. "A Finite Element Simulation of Longitudinal Impact Waves in Elastic Rods." In Materials with Complex Behaviour II, 3–17. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-22700-4_1.
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Magnusson, Christer, Josef Molvidsson, and Sven Zetterqvist. "Value creation and Return On Security Investments (ROSI)." In New Approaches for Security, Privacy and Trust in Complex Environments, 25–35. Boston, MA: Springer US, 2007. http://dx.doi.org/10.1007/978-0-387-72367-9_3.
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Muenstermann, Simon, Rainer Telle, Frederik Knauf, and Gerhard Hirt. "Semi-Solid Extrusion of Complex-Shaped Steel Rods Using Ceramic Dies." In Solid State Phenomena, 243–48. Stafa: Trans Tech Publications Ltd., 2008. http://dx.doi.org/10.4028/3-908451-59-0.243.
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Fyfe, H. B., M. Mlekuz, G. Stringer, N. J. Taylor, and T. B. Marder. "Rigid-Rod Transition Metal Acetylide Complexes, Oligomers, and Polymers for Nonlinear Optics." In Inorganic and Organometallic Polymers with Special Properties, 331–44. Dordrecht: Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-011-2612-0_22.
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Molday, Robert S., René Warren, Chris Loewen, and Laurie Molday. "Cyclic GMP-Gated Channel and Peripherin/rds-rom-1 Complex of Rod Cells." In Novartis Foundation Symposium 224 - Rhodopsins and Phototransduction, 249–64. Chichester, UK: John Wiley & Sons, Ltd., 2007. http://dx.doi.org/10.1002/9780470515693.ch14.
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Bauer, Paul J. "The Complex of cGMP-Gated Channel and Na+/ Ca2+K+Exchanger in Rod Photoreceptors." In Advances in Experimental Medicine and Biology, 253–74. Boston, MA: Springer US, 2002. http://dx.doi.org/10.1007/978-1-4615-0121-3_15.
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Anarova, Sh A., SH M. Ismoilov, and O. Sh Abdirozikov. "Software of Linear and Geometrically Non-linear Problems Solution Under Spatial Loading of Rods of Complex Configuration." In Intelligent Human Computer Interaction, 380–89. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-68449-5_38.
Full textConference papers on the topic "Complexos de rodi"
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Keskinen, Erno, Taina Vuoristo, Veli-Tapani Kuokkala, and Matti Martikainen. "Viscoelastic Wave Analysis of Hopkinson Split Bar System." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-81241.
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Axially elastic rods are basic machine elements in hydraulic hammers, pilers and percussive drills. The problem to analyze the motion history of such mechanisms is a very complex one, because the rods are simultaneously in large amplitude axial motion superimposed with a small amplitude elastic wave motion. The wave motion experiences division to reflected and transmitted components at each rod-rod interface depending on the current boundary stiffness. The wave motion in each rod can be computed by finite elements or alternatively in space of semidefinite eigenfunctions. The feasibility of these methods in solving wave propagation problems in multi-rod systems with nonlinearly behaving rod-rod interfaces has been investigated and evaluated. The object of the case study is a classical Hopkinson split bar apparatus used in experimental analysis of material response to shock pulses.
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Holloway, Mary V., Donald E. Beasley, and Michael E. Conner. "Investigation of Swirling Flow in Rod Bundle Subchannels Using Computational Fluid Dynamics." In 14th International Conference on Nuclear Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/icone14-89068.
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The fluid dynamics for turbulent flow through rod bundles representative of those used in pressurized water reactors is examined using computational fluid dynamics (CFD). The rod bundles of the pressurized water reactor examined in this study consist of a square array of parallel rods that are held on a constant pitch by support grids spaced axially along the rod bundle. Split-vane pair support grids are often used to create swirling flow in the rod bundle in an effort to improve the heat transfer characteristics for the rod bundle during both normal operating conditions and in accident condition scenarios. Computational fluid dynamics simulations for a two subchannel portion of the rod bundle were used to model the flow downstream of a split-vane pair support grid. A high quality computational mesh was used to investigate the choice of turbulence model appropriate for the complex swirling flow in the rod bundle subchannels. Results document a central swirling flow structure in each of the subchannels downstream of the split-vane pairs. Strong lateral flows along the surface of the rods, as well as impingement regions of lateral flow on the rods are documented. In addition, regions of lateral flow separation and low axial velocity are documented next to the rods. Results of the CFD are compared to experimental particle image velocimetry (PIV) measurements documenting the lateral flow structures downstream of the split-vane pairs. Good agreement is found between the computational simulation and experimental measurements for locations close to the support grid.
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Zhu, Wang, Zhang Chunyu, Li Aolin, and Yuan Cenxi. "Three Dimensional Modeling of the Thermo-Mechanical Performance of the Fuel Rods of a PWR." In 2017 25th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/icone25-66010.
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The fuel rods of pressurized water reactors operate under complex radioactive, thermal and mechanical conditions. Multiphysics has to be taken into account in order to evaluate their performance. Many existing fuel rod codes make great simplifications on analyzing the behavior of fuel rods. The present study develops a three dimensional module within the framework of a general-purpose finite element solver, i.e. ABAQUS, for modeling the thermo-mechanical performance of the fuel rods. A typical fuel rod is modeled and the temperature as well as the stress within the pellets are computed. The results show that the burnup levels have an important influence on the fuel temperature. The swelling of fission products cause dramatically increasing of pellet strain. The change of the cladding stress and radial displacement with the axial length can be reasonably predicted. It is shown that a quick power ramp or a reactivity insertion accident can induce high tensile stress to the outer regime of the pellet and may cause further fragmentation to the pellets.
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Ueno, Yoshihiro. "Computer Simulation of Bacterial Colony Formation with Multiplying Rods Producing a Chemotactic Factor." In SLOW DYNAMICS IN COMPLEX SYSTEMS: 3rd International Symposium on Slow Dynamics in Complex Systems. AIP, 2004. http://dx.doi.org/10.1063/1.1764172.
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Koda, Tomonori. "Molecular dynamics simulation of mixtures of hard rod-like molecules." In SLOW DYNAMICS IN COMPLEX SYSTEMS: 3rd International Symposium on Slow Dynamics in Complex Systems. AIP, 2004. http://dx.doi.org/10.1063/1.1764099.
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Nakamura, Hironori, Kazuhiro Oyama, Satoshi Hayakawa, Tomoaki Ogata, Seiichiro Maeda, and Takayuki Ozawa. "CFD Analysis Technique Development for Wire Contact Effect of Fuel Rods Within Next Generation FBR in Japan." In 2017 25th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/icone25-66307.
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Generally, the inside of a fuel subassembly of sodium cooled fast reactor (SFR) has complex geometry and this complexity makes it difficult to conduct computational fluid dynamics (CFD) utilizing cyclic boundary condition in a radial direction. However, present work has created a new modeling method which enables us to model only one rod with one wire (1-rod model) to represent periodically installed rods with wires, like an actual fuel subassembly. The axial geometry of the 1-rod model has one wire pitch length and has two extra buffer zones to reduce the influence of inlet and outlet boundary conditions. Since this 1-rod model requires low calculation load to represent flow field of a center rod in the fuel subassembly, the model allows the choice of increased number of mesh in both radial and axial directions. With this 1-rod model, three-dimensional (3D) thermal hydraulic simulation has been conducted to evaluate a peak local temperature caused by contact of a wire with the fuel rod cladding. As the coefficient of wire contact effect, the simulation obtained a value of 2.4, which means peak coefficient of fuel cladding temperature.
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Jing, Xiaoning, William C. Webster, Qi Xu, and Kostas Lambrakos. "Coupled Dynamic Modeling of a Moored Floating Platform With Risers." In ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2011. http://dx.doi.org/10.1115/omae2011-49553.
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A time domain coupled analysis capability has been developed to model the dynamic responses of an integrated floating system incorporating the interactions between vessel, moorings and risers in a marine environment. Hydrodynamic responses of the vessel allowing diffraction, radiation damping and wave drift forces on panelized bodies in addition to loads on Morison members, are modeled using the well-established program, MLTSIM. RodDyn, a finite element rod dynamics program, based on Garrett’s rod theory, is an efficient program to model the nonlinear dynamics of risers and moorings. The coupled MLTSIM-RodDyn suite integrates the nonlinear motions and structural analysis capabilities of RodDyn with the extensive hydrodynamic simulation capabilities of MLTSIM. With the fully-coupled dynamic analysis, the integrated system can be analyzed consistently. That is, the forces and moments applied by the rods to the platform are concurrent with the motions imposed on the rods by the platform at their multiple contact points. An asynchronous coupling of these two programs has been developed which allows for a fast simulation of this very complex problem. A worked example showing the nonlinear coupled analysis, is elaborated with systematical comparison with uncoupled analysis.
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Lin, Meng-Ju. "Relationship Between Distance of Photonic Crystal Rods Array and Wavelength of Light Propagating in Right-Angular, Cross, and Y-Shapes Waveguide." In 2008 Second International Conference on Integration and Commercialization of Micro and Nanosystems. ASMEDC, 2008. http://dx.doi.org/10.1115/micronano2008-70307.
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Photonic crystal is widely used in optical communication. Waveguide is one of important components used in optical communication. The performance of right-angular, cross, and Y shapes photonic crystal waveguide used in optical communication is investigated. Material used for photonic crystal is GaAs. Shape of photonic crystal rod is cylindrical rod. These rods are arranged to become matrix with constant distance. In the photonic crystal matrix, some rods are removed to form waveguide channel. Three shapes of waveguides are discussed. They are right-angular, cross, and Y shapes. The relationship between distances of circular photonic crystals and wavelength in propagation is discussed. Due to coupling of multi physical phenomena and complex geometry, a finite element method software called COMOSL is used to analyze performance of waveguide under different wavelength of light. It is found under different distance of photonic crystal rods array and wavelength, light could propagate along waveguide successfully or lost energy and decay. From results analyzed by COSMOL software, numerical data are obtained to classify light being able to pass waveguide successfully or not. By neural network method, equations between crystal rods array distance and wavelength to decide whether light can propagate through waveguide successfully or not are derived. They can be used to determine performance of light propagating in waveguide. For Y shape waveguide, bifurcation phenomena of light propagate in different channel of Y shape branch is found. It is found under different crystal pillar distance the light of different wavelength would propagate in one of the branch of the Y shape channel. The longer wavelength lights pass the upper channel and the shorter pass the lower. The results show that the bifurcation happens at the tendency if pillar distance increases the bifurcation wavelength also increases. From neural network method, equations to decide light propagate to upper or lower branch of Y shape waveguides are also obtained.
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Ilyin, Aleksei, Georgy Milovzorov, and Marat Khakimyanov. "Diagnostics of the Condition of Sucker-Rod Pumping Units after the Analysis of Wattmeter Cards." In 2019 International Conference on Electrotechnical Complexes and Systems (ICOECS). IEEE, 2019. http://dx.doi.org/10.1109/icoecs46375.2019.8949912.
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Tanaka, Motohiko. "Charge Inversion of a Macroion in Electrolyte Solvent: A Rotating Rod with Polyelectrolyte Counterions." In SLOW DYNAMICS IN COMPLEX SYSTEMS: 3rd International Symposium on Slow Dynamics in Complex Systems. AIP, 2004. http://dx.doi.org/10.1063/1.1764145.
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