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1
Bangun, Nimpan. "NMR study of palladium methoxide and palladium carbomethoxide complexes." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-12052009-020137/.
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Clentsmith, Guy Kenneth Bruce. "Dinuclear palladium complexes with bridging hydrides." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/29800.
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The palladium hydride dimer, [(dippp)Pd]₂(µ--H)₂, (2) (dippp = 1,3-bis(diisopropylphosphino)propane), was synthesized, and its interaction with lithium tetraethylborate examined. When the two compounds were mixed in stoichiometric amounts high yields of the adduct, [(dippp)Pd]₂(µ-H) ₂•LiBEt₄ (1) — previously isolated adventitiously by a co-worker — were obtained. Variable temperature ³¹P{¹H} NMR spectroscopy showed a condition of chemical equilibrium between 2 and 1, but the value of the equilibrium constant, Keq, could not be determined owing to its large magnitude. Extension of this chemistry to other sources of Li⁺ led to the isolation of the aluminate adduct, [(dippp)Pd]₂((µ-H)₂,•LiA1Et₄ (3). Likewise when NaBEt₄ was substituted an adduct formulated as [(dippp)Pd]₂(µ-H)₂•NaBEt₄ (4) was obtained.
The interaction of tetraethylborate salts with other transition-metals was also examined, with evidence of adduct formation for both [(dippp)Rh]₂(µ-H)₂ and [(dippp)Ni]₂(µ-H)₂ (6) with LiBEt₄. It was not possible to isolate these compounds as analytically pure samples. This general interaction is discussed in terms of metal basicity.
The reactivity of 2 towards organic donor species was also studied. Addition of excess donor results in the formation of tricoordinate Pd(0) species: (dippp)Pd(ɳ²-H₂C=CH₂) (5), (dippp)Pd(PPh₃) (7), and (dippp)Pd(DMAD) (8) (DMAD = dimethylacetylenedicarboxylate) were thus isolated. When a stoichiometric equivalent of donor was added to 2, no dimeric intermediates could be observed.Science, Faculty of
Chemistry, Department of
Graduate
3
Ford, S. "New palladium complexes containing organoselenium ligands." Thesis, Swansea University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.636990.
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The aim of the work contained within this thesis was to investigate the reactions of bicyclic 1,2,3-selenadiazoles and their diselenin derivatives with Pd (0) phosphine complexes. Chapter one is a review of previous research on organoselenium ligands that have been shown to bond to palladium and platinum. It also summaries other relevant chemistry of the ligands under investigation. Chapter two describes the reactions between a variety of palladium trialkylphosphine complexes, and cycloalkeno-1,2,3-selenadiazoles. It includes the first analysis by x-ray crystallography of a simple uncoordinated bicyclic 1,2,3-selenadiazole, and full characterisation of all the products obtained. Chapter three describes the reactions between tetrakis(triphenylphosphine)palladium and both cycloalkeno-1,2,3-selenadiazoles and their diselenin derivatives. Also included in this section is a new method for the preparation of bis(cycloalkeno)-1,4-diselenins. Chapter four looks at the reaction between the palladium starting materials used in chapter two, and bis(cycloalkeno)-1, 4-diselenins. The products obtained are fully characterised, and further research into their chemistry is documented in chapter five. Here, they are shown to undergo bridge cleavage reactions with both monodentate and bidentate phosphine ligands. This chapter also includes the direct synthesis of palladium diselenolenes containing 1,2-bis(diphenylphosphino)ethane. Experimental details concerning the synthesis of all complexes, both products and starting materials, used in this study are contained in the final chapter six.
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Spankie, S. A. A. "Ylide complexes of palladium and platinum." Thesis, Heriot-Watt University, 1987. http://hdl.handle.net/10399/1018.
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Cairns, Graham R. "Hydrogenation catalysts from supported palladium complexes." Thesis, University of Glasgow, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360177.
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Kuma, Karl Earl Adjetey. "A study of palladium cyclopentadienyl complexes." Thesis, University of Salford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299126.
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Dooley, Ruth Elizabeth. "Isomerisation of palladium π-allyl complexes." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/15976.
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The palladium-catalysed asymmetric allylic alkylation is a mild and versatile bond forming reaction between a nucleophile and allylic electrophile. The wide scope of nucleophiles used, and the high regio- and stereoselectivity obtainable renders this transformation an important technique in enantioselective synthesis. The mechanism is known to go via a key palladium π-allyl intermediate, followed by nucleophilic addition occurring at the terminal allylic carbon. Both the formation of the palladium π-allyl, and the nucleophilic addition to generate the alkylated product and palladium(0) proceed with high levels of inversion of stereochemistry, and both provide an opportunity for the induction of stereochemistry. However in the case of ligand controlled nucleophilic addition memory effects have been observed. The epimerisation of the palladium π-allyl before nucleophilic attack is key to achieving high levels of selectivity when racemic starting materials and chiral ligands are employed. Previous work in the Lloyd-Jones group has determined that prolonging the lifetime of the palladium π-allyl species, either by the use of weakly coordinating counter ions or slow addition of the nucleophile reduces this memory effect, however increasing the rate of epimerisation would have a result in a similar effect. One of the mechanisms resulting in the epimerisation of the palladium π-allyl species is mediated by palladium(0), however the details of the mechanism are not well understood. We describe the synthesis of a diastereotopic palladium cyclohexenyl ester and labelled the complex with 108palladium and d3 at the cyclohexenyl ester. Using simultaneous 31P NMR and mass spectrometry, we have acquired strong evidence against mechanisms involving a single electron transfer, as proposed by Stille, of formation of a dinuclear palladium(I) species followed by an inversion event, and we have gained evidence supporting the direct nucleophilic addition of the palladium(0), resulting in inversion of stereochemistry. The differences in rates of nucleophilic attack involving monodentate and bidentate phosphine ligands on both the palladium I-cyclohexenyl ester have also been explored. Throughout the mechanistic investigation, it was noted that the 31P NMR spectroscopy experiment used gave non-quantitative results, and in fact the differences in quantification of the species varied with the spectrometer used. We also describe our investigations into where these differences arise from and an optimum set of parameters for quantitative 31P NMR spectroscopy. The conclusions are also applicable to other heternuclear NMR spectroscopic experiments.
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Alshgari, Razan. "Crystal engineering of palladium terpyridine complexes." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/47726/.
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The ability of 2,2':6',2"-terpyridine (terpy) to chelate to a wide variety of metal ions has led to the synthesis of different metal-terpyridine complexes. In addition, there are different synthetic strategies have been improved, allowing 2,2':6',2"-terpyridine and its derivatives to find a wide range of applications assensors and catalysts. This thesis concerns the synthesis of a series of Pd(terpy) complexes with different para- and meta-substituted pyridine ligands and their properties are studied by X-ray crystallography. In order to extend the experimental observations and the range of applicability of the proposed interpretation, another system involving the tridentate aromatic nitrogen donor 4,4',4''-tri-tert-butyl-2,2':6',2''-terpyridine (tBu3-terpy) has been examined. A range of N,N-bidentate ligandsare introduced in next section. These can be potentially used to bridge two metal centres. The reactivity of [Pd(terpy)(NCCH3)](CF3SO3)2 was investigated with a wide range of N,N-bidentate ligands. Substitution of the acetonitrile ligand of [P(terpy)(NCCH3)](CF3SO3)2 with these ligands was found to be efficient and facile with reactions occurring at room temperature. Extension of this reaction to meso-tetra (4-pyridyl)porphyrin results in tetranuclear Pd(terpy) complex and affords [{Pd(terpy)}4(H2T(4-Py)P)](CF3SO3)8. In Chapter 6, similarly to terpyridine, 2-phenyl-4,6-bis(2-pyridyl)-1,3,5-triazine (pbptz) is coordinated to palladium as a tridentate ligand and no complex was seen to adopt any of the other potential binding modes for this molecule.
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Zuideveld, Martin Alexander. "Solvolysis of palladium-carbon bonds in palladium(II) complexes containing diphosphine ligands." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2001. http://dare.uva.nl/document/60731.
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Haaren, Richard Johannes van. "Palladium and rhodium allyl complexes in catalysis." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2002. http://dare.uva.nl/document/64738.
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Dewa, Shaliza Zaini. "Novel 3,3-dialkyldiaziridine platinum and palladium complexes." Thesis, University of Sussex, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296548.
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Louw, Marissa. "New platinum and palladium complexes: their anticancer application." Thesis, Nelson Mandela Metropolitan University, 2010. http://hdl.handle.net/10948/d1016218.
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Novel non-leaving groups were employed in this dissertation to synthesize platinum complexes which can assist in the understanding or improvement of anticancer action. Emphasis was placed on (NS)-chelate and (NN)-chelate platinum complexes. Bidentate (NS)-donor ligands were used as non-leaving ligands in the synthesis of platinum(II) complexes with iodo, chloro, bromo and oxalato groups as leaving groups. These complexes were synthesized and studied since many questions regarding the interaction of sulfur-donors and platinum still exist. These relate to thermodynamic and kinetic factors and their influence on anticancer action. In this dissertation the properties of novel platinum(II) complexes of a bidentate ligand having an aromatic nitrogen-donor atom in combination with a thioethereal sulfur atom capable of forming a five-membered ring with platinum(II) were studied. The general structure of the (NS)-ligands used was 2-((alkylthio)methyl)pyridine. Alkyl groups used were methyl, ethyl, propyl, benzyl and phenyl. Amine complexes of platinum have been studied extensively in the past. However, attention was given to novel aspects of substituted pyridine and imidazole ligands and their corresponding complexes. Amongst these are 2-(2-methylaminoethyl)pyridine, 1-methyl-2-methylaminoethylimidazole and 1-methyl-2-methylaminobenzylimidazole. The leaving groups included chloro, bromo and oxalato. Mononitroplatinum(IV) complexes were prepared using novel synthetic methods. Selected platinum(II) amine complexes were used as starting materials for this synthesis. Some of these compounds exhibit promising anticancer behaviour. (Trans-(R,R)-1,2-diaminocyclohexane)(oxalato)(mononitrochloro)platinum(IV) is a particularly good anticancer agent and has been patented internationally. All these complexes were characterized using mass spectrometry, chromatography, thermogravimetric analysis, kinetic aspects such as ligand exchange rates and finally their anticancer action against three different cancer cell lines was evaluated via cytotoxicity assays. Some of the compounds exhibited particularly good anticancer potential.
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Lerma, Israel Consea. "Transformations Mediated by Palladium-(N-Heterocyclic)Carbenes Complexes." Thesis, University College London (University of London), 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.498701.
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Clapham, Sarah. "Organometallic amino and amido complexes of palladium(II)." Thesis, University of Salford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420460.
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Broadwood-Strong, Gillian. "Novel phosphine complexes of platinum and palladium (0)." Thesis, University of Sussex, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385600.
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Bryce, Garry Thomas. "Palladium acylation catalysts and osmium cluster arene complexes." Thesis, University of Edinburgh, 1998. http://hdl.handle.net/1842/15491.
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The acyl palladium complex (bpy)Pd(COMe)(I) (bpy = 2,2'-bipyridyl) was synthesised, and reacted with a variety of different alkenes, cyclic alkenes and dienes, and arenes in an attempt to yield the inserted acyl complexes {(bpy)Pd(CxRYCOMe)}. The inserted complexes were the first stage in setting up a catalytic reaction with the Palladium complex acting as a catalyst in the synthesis of an acylated arene. The osmium cluster Os3(CO)10(NCMe)2, was reacted with a series of functionalised arenes of the type C6H4R1R2 (where R1 = H, R2 = F, Cl, Br, CHCH3, C(CH3)CH2 and Me; R1 = R2 = Me, R1 = R2 = C(CH3)CH2) yielding clusters of the type Os3(CO)9H2(C6H2R1R2). The crystallographic and spectroscopic data provides evidence of the different geometric forms that the complexes demonstrate with the different types of ligands. The osmium arene complexes were reacted further using a Friedel-Crafts acylation reaction to acylate the arene ring when it is attached to the cluster. The resultant complexes show a shifting of the IR bands in the IR to higher wavenumbers. The compound Os3(CO)9H2(C2H3F) reacted with 2-butyne yielding the complexes Os3(CO)8(H)(CH2CHCHCH3)(C6H3F) and Os3(CO)8H2(η2-2-butyne)(C6H3F) which were identified crystallographically and spectroscopically. These two complexes show two different bonding modes of the butyne ligand to metal centre.
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Eck, Charles Paul. "Synthesis and reactions of low-valent palladium complexes." Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185556.
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The reaction of Pd(NO₂)₂L₂(L = P(4-Cl-C₆H₄)₃, PEtPh₂,PMePh₂) with CO was investigated. A technique was developed to analyze the gaseous products of the reaction, CO₂ and N₂O, and to quantify the molar amounts of CO₂ and N₂O evolved using infrared spectroscopy. The reaction solution was analyzed by variable temperature ultraviolet-visible spectroscopy to give evidence for at least five species in the reaction solution. The reaction with CO leads to three moles of CO₂ and one mole of N₂O per mole of Pd(NO₂)₂L₂. Less than stoichiometric amounts were observed when significant amounts of nitrosyl complexes remained in solution, as, for example, when L = PMePh₂ at low concentrations. The initial rate of CO₂ evolution is dependent upon the concentration of the starting material and precedes N₂O evolution. The rate of N₂O evolution depends upon the phosphine ligand and the palladium concentration with no N₂O being evolved at low Pd(NO₂)₂L₂ concentrations. The observed initial rate constant for the disappearance of Pd(NO₂)₂ (PMePh₂)₂ is 0.04642 min⁻¹ (25°C, 1.1 x 10⁻⁴ M), and the observed initial rate constant for the evolution of CO₂ is 0.001963 min⁻¹ (25°C, 0.95 x 10⁻⁴ M), indicating the initial formation of the five-coordinate intermediate, PdCO(NO₂)₂L₂, prior to CO₂ evolution. This intermediate subsequently evolves CO₂ and forms the nitro-nitrosyl complex, Pd(NO₂)(NO)L₂. A third intermediate was identified as the five-coordinate PdCO(NO₂)(NO)L₂. This third species also decomposed, liberating a second mole of CO₂ and producing the dinitrosyl complex, Pd(NO)₂L₂. It is proposed that the dinitrosyl complex subsequently undergoes bimolecular reactions leading to the evolution of the third mole of CO₂ and to the formation of N₂O.
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Selander, Nicklas. "Catalytic Functionalization of Allylic Substrates by Palladium Pincer Complexes." Doctoral thesis, Stockholms universitet, Institutionen för organisk kemi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-39065.
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This thesis is based on the development of novel catalytic reactions for the synthesis and application of organometallic reagents. The main focus is directed towards organoboronate derivatives. We developed an efficient procedure for converting allylic alcohols to the corresponding allylboronates using palladium pincer complexes as catalysts. The reactions were performed under mild conditions with high selectivity, allowing further one-pot transformations. Using this approach, a variety of stereodefined homoallylic alcohols and amino acid derivatives were synthesized via trapping of the in situ generated allylboronate derivatives with an appropriate electrophile. The synthetic scope of these types of multi-component reactions is broad as many different substrate allylic alcohols may be used together with various electrophiles. Several aspects of these reactions were studied, including different reagents, catalysts and electrophiles. Furthermore, we studied the possibility to use oxidizing reagents as an essential component in the functionalization of olefins. Two main strategies were utilized for these catalytic methods using palladium pincer complexes. The functional group was either transferred from the oxidizing reagent, or introduced via an oxidation-transmetallation route. We propose that both methods involve palladium(IV) intermediates thus expanding both the coordination sphere of palladium and the synthetic scope of pincer complex catalysis.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 11: In press.
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Kato, Kazuhiko. "Some Asymmetric Reactions Catalyzed by Chiral Palladium(II)Complexes." 京都大学 (Kyoto University), 1998. http://hdl.handle.net/2433/182447.
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Silcock, Peter J. "Nickel and palladium complexes of di-N-heterocyclic carbenes." Thesis, University of Oxford, 1999. https://ora.ox.ac.uk/objects/uuid:679dade4-1d16-4918-b155-996250516783.
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This thesis is concerned with the synthesis of two di-N-heterocyclic carbene ligands, and their reactivity towards nickel and palladium precursors in order to synthesise new organometallic pre-catalysts for a number of important reactions. The catalytic properties of a new rhodium C60 compound are also investigated, with relevance to the evaluation of C60 as a hydrogen storage medium. Chapter 1 reviews the preparation and chemistry of N-heterocyclic carbenes, emphasising their organometallic reactivity and role as ancillary ligands in homogeneous transition metal catalysis. An overview of relevant nickel and palladium catalysis is also presented, including olefin polymerisation, olefm / CO copolymerisation and Heck coupling reactions. Chapter 2 describes the synthesis and characterisation of the dicarbene ligands tBuCCmeth and tBuCCeth and their reactions with various nickel precursors in attempts to prepare chelating dicarbene nickel cis-dihalide complexes. The synthesis, characterisation and chemical reactivity of the cations [Ni(tBuCCmeth)2]2+, [(tBuCCmeth)NiCl(PMe3)] + and [(tBuCCeth)NiCl(PMe3)]+ is detailed, and their X-ray structures are compared. The unsuccessful preparation of [Ni(tBuCCeth)2] 2+ and the relative stability of the monocations with respect to dicarbene substitution is discussed and attributed to steric factors. Chapter 3 describes the synthesis, characterisation, reactivity and catalytic studies of simple nickel and palladium cis-dimethyl complexes of the chelating dicarbene ligands. Variable temperature 1H NMR spectroscopy showed contrasting rates of thermal hydrocarbon elimination from Ni(tBuCCmeth)Me2 and Ni(tBuCCeth)Me2, which has previously been observed for chelating bis-phosphine analogues with various P,P' linkages (CH2)n . These observations further corroborate the analogy between dicarbene and 6/s-phosphine ligands. It was demonstrated that the compounds Pd(tBuCCmeth)Me2and Pd(tBuCCeth)Me2 are effective pre-catalysts for the Heck coupling of 4-bromoanisole and n-butyl acrylate. In addition cations of the type [(tBuCCmeth/eth)PdMe(L)]+ (L = pyridine, THF) which are relevant to olefin / CO copolymerisation were prepared. The X-ray structures of M(tBuCCeth)Me2 (M = Ni, Pd) are discussed as well as the synthesis and structural characterisation of [(|Li-tBu CC meth){Ni(PMe3)Me2}2]. Chapter 4 presents a brief introduction to some relevant C60 chemistry and to the concept of hydrogen storage. The synthesis and characterisation of a new rhodium Ceo compound is described. The compound catalysed the hydrogenation and hydroformylation of simple alkenes as well as the hydrogenation of C60 to C60H36 . The recovery of hydrogen gas from C60H36 was investigated in order to evaluate C60 as a hydrogen storage medium. Chapter 5 outlines the experimental details for the synthesis, characterisation, reactions and catalytic studies of the new compounds described in the preceding three chapters. Chapter 6 presents the characterising data for the new compounds described in chapters 2 and 3. Appendices contain details of the crystallographic data for the eight structurally characterised compounds described in chapters 2 and 3.
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Almeida, Leñero Karina Quetzaly. "Activation of dihydrogen by ruthenium, platinum and palladium complexes." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2002. http://dare.uva.nl/document/61365.
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Ward, Caroline Victoria. "Phosphinothioether and thiolate complexes of ruthenium, palladium and rhenium." Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401050.
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Campbell, Michael Glenn. "Synthesis, Structure, and Reactivity of New Palladium(III) Complexes." Thesis, Harvard University, 2014. http://dissertations.umi.com/gsas.harvard:11289.
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Palladium is one of the most common and versatile transition metals used in modern organometallic chemistry. The chemistry of palladium in its 0, +II, and +IV oxidation states is well-known; by comparison, the chemistry of palladium in its +III oxidation state is in its infancy. The work in this thesis involves the study of previously unknown Pd(III) complexes, including applications in materials chemistry and catalysis.Chemistry and Chemical Biology
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Arentsen, Katherine. "Application of palladium N-heterocyclic carbene complexes in catalysis." Thesis, University of Sussex, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430951.
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Henderson, William. "Four-membered metallacyclic complexes of platinum, palladium and nickel." Thesis, University of Leicester, 1987. http://hdl.handle.net/2381/33732.
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Chapter 1 reviews the literature concerning the principal synthetic routes to metallacyclobutane, metallacyclobutan-3-one (?3-oxodimethyl-enonethane), and four-membered cyclic ylide complexes of platinum, palladium, and nickel, which contain the M-C-X-C ring system (X=C,S, or P). The preparation and characterisation of the first examples of metallathietane-3, 3-dioxide complexes of platinum, palladium, and nickel, [M{CHRS (O) 2CHR}L2], are presented in Chapter 2. The molecular structures of three of these complexes establish the presence of puckered four-membered rings, together with the presence of a hetero-allylic contribution to the bonding. Preliminary investigations into the reactivity of these metallathietane- 3, 3-dioxide complexes are detailed in Chapter 3. Ligand substitution reactions of the complex [Pt{CHPhS(O)2CHPh}(SEt2)2] afford a range of platinathietane-3,3-dioxide complexes. A study of the reactions of platinathietane-3,3-dioxide complexes with alkyl isocyanides shows that phenyl substituted complexes undergo ligand substitution, whereas benzoyl or methoxycarbonyl substituted complexes undergo a ring insertion reaction to afford the zwitterionic complexes [Pt{CH(C0R)S(O)2C(COR)C:- NHR'}(CNR')(L) ]. Chapter 4 describes the synthesis of platinathietane-3-oxide complexes, crystallographic and n.m.r. data indicating the presence of puckered and non-fluxional four-membered ring systems, with the sulphinyl oxygen in an equatorial environment. The sulphoxide and equatorial benzoyl groups of the complex [Pt{CH(COPh)S (O)CH(COPh)} (PPh3)2] co-ordinate to palladium (II) or rhodium (I) centres to afford five-membered chelate ring products. The final Chapter describes the synthesis of diphenyl-substituted oxo- dimethylenemethane (metallacyclobutan-3-one) complexes of platinum and palladium using the dianion K2[PhCHC(O)CHPh]. The molecular structure of the complex [Pt{?3-CHPhC(O)CHPh} (AsPh3)2] establishes the presence of an n3-oxodimethylenemethane ligand. The fluxional behaviour of these diphenyl oxodimethylenemethane complexes is shown to be dependent on the mode of substitution of the phenyl rings on the oxodimethylene methane ligand, with cis-diequatorial complexes being rigid in solution, and the trans-disubstituted complex trans- [Pt{?3 -CHPhC (O) CHPh} (PPh3)2] being fluxional.
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Duncan, Daniel. "Synthesis, catalysis and recycling studies of perfluoroalkylated palladium complexes." Thesis, University of Leicester, 2007. http://hdl.handle.net/2381/29992.
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A range of fluorous monodentate triarylphosphines were synthesised using novel chemistry and modified literature methods. the corresponding complexes were shown to be more active in the Suzuki reaction, compared with the non-fluorous derivative, triphenylphosphine. However, the catalysts simply decomposed under the reaction conditions to form palladium black making it impossible for these fluorous catalysts to be recycled.;The synthesis and coordination chemistry of fluorous and non-fluorous pincer phosphines has been investigated. Both palladium pincer catalysts successfully catalyse a range of Heck and Suzuki reactions. However, recovery and reuse was only possible with the fluorous pincer catalyst, which could be successfully recovered and reused three times in the Heck reaction with no loss in activity. In the Suzuki reaction, recovery and reuse of the fluorous pincer catalyst was possible, however, decomposition of the catalyst was detected under the reaction conditions leading to an inevitable loss in activity.;A range of fluorous and non-fluorous monodentate, bidentate and pincer NHC ligands and palladium complexes were synthesised using novel chemistry and modified literature methods. The monodentate NHC complexes were evaluated in Heck reactions. The recovery and reuse of the fluorous carbene complexes were evaluated with differing success. Under homogenous reaction conditions, decomposition of the light fluorous catalyst was detected upon recovery of the catalyst. Conversely, when supporting the heavily fluorinated carbene complex on Fluorous Reverse Phase Silica Gel (FRPSG), the catalyst was successful used three times. However, due to poor recovery of the support, inevitable loss in product conversion was observed.
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Shaffer, Andrew R. "Synthesis, Reactivity, and Catalysis of 3-Iminophosphine Palladium Complexes." University of Toledo / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1248288981.
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Almeida, Lenero Karina Quetzaly. "Activation of dihydrogen by ruthenium, platinum and palladium complexes." Toulouse 3, 2002. http://www.theses.fr/2002TOU30240.
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Petersen, Allan Robertson. "Dioxygen insertion studies into platinum and palladium alkyl complexes." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/9608.
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Chapter 1 provides an overview of the oxidation of methane by platinum salts known as Shilov chemistry. This includes platinum complexes used for the selective oxidation of methane to methyl bisulfate. Attention is paid to model platinum complexes that have been synthesised to explore the oxidation of methane using dioxygen as the oxidant. Chapter 2 describes two sets of tridentate N donor ligands that have been synthesised. The first set contains 6,6ʹʹ-disubstituted-2,2ʹ:6ʹ,2ʹʹ-terpyridine ligands, of these two new ligands 6,6ʹʹ-di(methylamino)-2,2ʹ:6ʹ,2ʹʹ-terpyridine and 6,6ʹʹ-dimethoxy-2,2ʹ:6ʹ,2ʹʹ-terpyridine have been synthesised and fully characterised. The second set contains non-terpyridine tridentate ligands. The synthesis and characterisation of novel cationic platinum(II) methyl complexes bearing these ligands is described in Chapter 3. The structures of some of these complexes have been determined by X-ray crystallography. Further, the reactivity of the complexes towards dioxygen is reported and how different reactivity is imparted by the different ligands is discussed. The ability of some of these platinum(II) methyl complexes to insert dioxygen into their M-Me bonds arises from the steric interaction between the Pt-Me ligand and the substituents in the 6- and 6ʹʹ-positions on the terpyridine ligand. Chapter 4 describes a study into the mechanism of the insertion of dioxygen into a Pt-Me bond. This includes deuterium labelling experiments, which led to the discovery of the exchange of methyl ligands between platinum(II) and palladium(II) centres. A mechanism for this exchange involving the formation of a MII-MII dimer is proposed. In addition, the decomposition of a palladium(II) methylperoxo complex to give an intriguing new metallacyclic hemiacetal alkoxide complex is described. A possible mechanism for the formation of this new palladium(II) complex is discussed. The synthesis and characterisation of the new compounds discussed in Chapters 2-4 are reported in Chapter 5.
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Shaffer, Andrew Ronald. "Synthesis, reactivity, and catalysis of 3-iminophosphine palladium complexes /." Connect to full text in OhioLINK ETD Center, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1248288981.
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Thesis (Ph. D.)--University of Toledo, 2009.Typescript. "Submitted as partial fulfillment of the requirements for the Doctor of Philosophy in Chemistry." Includes bibliographical references (leaves 183-217).
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Haddou, Baptiste. "Études mécanistiques de réactions impliquant des complexes de palladium." Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEE020/document.
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Cette thèse porte sur l’étude mécanistique de réactions mettant en jeu des complexes de palladium. Deux systèmes différents sont étudiés, mettant ainsi en évidence des approches mécanistiques à différents niveaux. La première étude réalisée concerne l’addition oxydante de complexes [palladium - ligands azotés] sur des iodoarènes. Une cinétique d’ordre 2 en palladium(0) a été mise en évidence expérimentalement, pour une grande variété de conditions (ligands, solvants, iodoarènes). Un mécanisme coopératif faisant intervenir l’activation de la liaison CI par un complexe de palladium, suivi par l’insertion oxydante d’un deuxième complexe de palladium a été proposé et étudié par DFT. La deuxième étude porte sur formation d’oxazolidine-2,4-diones à partir d’adduits de Passerini, catalysée au palladium. L’objectif est ici de déterminer les intermédiaires mis en jeu dans cette réaction impliquant la formation de 3 nouvelles liaisons sur le squelette carboné. Une double réaction de Tsuji-Trost a été mise en évidence et le rôle particulier de l’allylméthylcarbonate utilisé a été étudié. A la lumière de ces résultats, un cycle catalytique a été proposé. Cette étude montre le potentiel de la compréhension détaillée des phénomènes à l’échelle moléculaire pour imaginer de futurs développementsIn this thesis, the mechanistic study of reactions involving palladium complexes is presented. Two systems have been studied, with different levels of mechanistic investigation. The first study aims at explaining the peculiar behavior of palladium ligated to nitrogen-containing ligands in the oxidative addition on iodoarenes. A second order in palladium(0) reaction rate has been experimentally demonstrated for various conditions (ligand, solvent, iodoarene). A cooperative mechanism involving the pre-activation of the C-I bond by a palladium complex prior to the oxidative insertion itself has been proposed and studied by DFT. In the second study, the palladium-catalyzed formation of oxazolidine-2,4-diones from Passerini adducts is investigated. The goal is to determine the relevant intermediates of the reaction and to explain the formation of the three new bonds. Two Tsuji-Trost reactions occur and the special role of allylmethylcarbonate has been studied. This mechanistic study highlights the potential of thorough understanding of mechanisms at the molecular level to envision further synthetic developments
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Grevin, Jérôme. "Hydroestérification par le formiate de méthyle catalysée par des complexes du palladium." Toulouse, INPT, 1993. http://www.theses.fr/1993INPT035G.
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La catalyse de l'addition directe du formiate de methyle sur l'ethylene pour obtenir selectivement du propionate de methyle en presence de complexes du palladium a ete etudiee. Le precurseur dichlorobis tri(n-butyl) phosphine palladium a permis de generer une espece active palladium-hydrure par reaction avec le borohydrure de sodium et un leger exces de tri(n-butyl) phosphine. Ce systeme catalytique a permis d'obtenir une activite correcte et une tres haute selectivite dans l'ester attendu. Un cycle catalytique a ete propose. La synthese de plusieurs complexes contenant le groupement carbomethoxy a ete realisee. Les tentatives d'introduction d'un deuxieme ligand hydrure ou benzoyle pour en etudier leur couplage ont montre que la configuration du complexe etait systematiquement trans. Des que l'isomerisation en position cis est provoquee, le groupement carbomethoxy se decarbonyle. Il en resulte, dans le cas du ligand benzoyle, la formation de l'ester et non du ceto ester. Un complexe stable du palladium zerovalent, contenant un ligand triphosphine, a ete prepare et sa structure aux rayons x realisee
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Lastra, Calvo Nuria. "Synthesis of novel aminomethylphosphine complexes." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/17984.
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A new series of aminomethylphosphine ligands incorporating a PCN backbone and a pendant amine were synthesised using a phosphorus Mannich condensation reaction. Their coordination capabilities were investigated with late transition metal centres. Following a procedure well established within our research group, several phosphines were obtained using {P(CH2OH)4}Cl (THPC) in two steps. Firstly, THPC was reacted with various ortho and para anilines to give phosphonium salts P{CH2N(H)R}4Cl (R = C6H5, o-MeC6H4, o-i PrC6H4, o-t BuC6H4, o-FC6H4, o-CF3C6H4, o-{C(Me)=CH2}C6H4, p-MeC6H4, p-i PrC6H4, p-FC6H4 and p-EtC6H4). Secondly, these new salts were reacted with Et3N to obtain the cyclic RN(H)CH2P{(CH2)3(NR)2} phosphines (R = para-substituted anilines) or with KOt Bu to obtain acyclic P{CH2N(H)R}3 phosphines (R = ortho-substituted anilines) and cyclic P{CH2N(R)CH2}2P diphosphines (R = ortho-substituted anilines). Double condensation was observed in the 31P{1 H} NMR of cyclic phosphines RN(H)CH2P{(CH2)3(NR)2} to form {(CH2)3(NR)2}PCH2N(R)CH2P{(CH2)3(NR)2} diphosphines. Some cyclic phosphines were investigated under a wide range of conditions with Ph2PCH2OH giving asymmetric Ph2PCH2N(R)CH2P{(CH2)3(NR)2} diphosphines along with symmetric diphosphines counterparts and other phosphorus coproducts according to 31P{1 H} NMR and MS. A novel bicyclic OP{CH2N(R)CH2}3PO diphosphine (R = p-MeC6H4) was obtained as crystalline solid from the filtrate of the reaction between RN(H)CH2P{(CH2)3(NR)2} and Ph2PCH2OH and it was characterised by X-ray spectroscopy. Attempts to synthesise this diphosphine from P(CH2OH)3 and p-MeC6H4 were unsuccessful. The family of aminomethylphosphine ligands was extended by treating Ph2PCH2OH or CgPCH2OH (Cg = 1,3,5,7-tetramethyl-2,4,8-trioxa-6-phosphaadamantane) with various primary amines to afford R(H)NCH2PR'2 (R' = Cg or Ph). Symmetric Ph2PCH2N(R)CH2Ph2 diphosphines were observed in the 31P{1 H} NMR spectra indicating that phosphines with Ph2P-moiety were more susceptible to undertake a second condensation. Novel asymmetric o-{Ph2PCH2C(H)(CH3)}C6H4N(H)CH2PPh2 diphosphine was synthesised by treatment of o-{C(Me)=CH2}C6H4NH2 with Ph2PH to afford o-{Ph2PCH2C(H)(CH3)}C6H4NH2 followed by condensation of the amino group with Ph2PCH2OH. Analogous o-{CgPCH2C(H)(CH3)}C6H4NH2 phosphine was also obtained. The coordination capabilities of selected compounds was studied with late transition metal precursor such as Pt(II), Pd(II) and Ru(II). Monophosphine compounds acted as Pmonodentate ligands to form square planar cis and trans MCl2L2 (M = Pt and Pd) complexes. However, whereas cyclic ligands RN(H)CH2P{(CH2)3(NR)2} afforded cisMCl2L2, acyclic ligands P{CH2N(H)R}3 afforded trans-MCl2L2 along with cis-PtCl2L2 in some cases. Those phosphines which conducted double condensation adopted a P,Pchelate mode to form a 6-membered M-P-C-N-C-P to afford cis-MCl2L (M = Pt and Pd). More interesting is the rarely observed P,P-bridging mode exhibited by P{CH2N(R)CH2}2P ligands to form homobimetallic cis-(PtCl2L)2 complexes and {RhCl2(η5 -Cp*)}2L complexes. These metal compounds were obtained and characterised by in situ NMR however their structures were further supported by simulated 31P{1 H} NMR and X-ray studies. Asymmetric Ph2PCH2N(R)CH2P{(CH2)3(NR)2} diphosphines coordinated to Pt(II) in a P,P-chelate fashion affording a mixture of cis and trans bis(chelate) (PtL2)Cl2. Complex in trans geometry was isolated and the structure was further supported by X-ray crystallography. The coordination capabilities of the ligands were investigated with Ru(II) metal centre revealing 'piano-stool' structure of the type RuCl2(η6 -p-cymene)L where the monophosphines adopted a P-monodentate mode and {RuCl2(η6 -p-cymene)}2L where the diphosphines adopted a P,P-bridging mode. Preliminary studies with selected Ru complexes were carried out to investigate their potential catalytic activity to trap CO2 by its insertion into the Ru-Cl bond which suggested that the chloride needs to be substituted by a hydride prior the CO2 insertion. Compounds were characterised by spectroscopic techniques and the structure of some phosphines was further supported by X-ray crystallography.
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Boysen, Ryan Bradley. "Development of palladium L-edge X-Ray absorption spectroscopy and its application on chloro palladium complexes." Thesis, Montana State University, 2006. http://etd.lib.montana.edu/etd/2005/boysen/BoysenR0506.pdf.
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X-ray Absorption Spectroscopy (XAS) is a synchrotron-based experimental technique that can provide information about geometric and electronic structures of transition metal complexes with unoccupied d orbitals. Combination of metal L-edge and ligand K-edge XAS has the potential to define the experimental ground state electronic structure. We developed a quantitative treatment for Pd L-edge spectroscopy based on the already established Cl K-edge XAS for a series of chloro palladium complexes, which are precatalysts in numerous organic transformations. We found that Pd-Cl bonds are highly covalent (23% per Cl in [PdC4]2-, 34% per Cl in [PdCl6]2-, and 46% in PdCl2). Dipole integrals for Pd(2p→4d) transitions of 42 eV for Pd(II) and 48 eV for Pd(IV) LIII-edges and 39 eV and 35 eV, respectively, at these Pd oxidation states for the LII-edges were determined. Application of the metal-ligand covalencies and transition dipole integrals by describing the ground state bonding in PdCl2 with bridging Cl ligands was demonstrated. In future studies, a similar approach will be utilized for palladium phosphine, allyl, olefin complexes in order to define their experimental electronic structure and correlate this with their observed reactivity.
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Bigeault, Julie. "Nouvelles réactions de cycloaddition catalysées par des complexes acides phosphineux-métal (Pd, Pt)." Aix-Marseille 3, 2007. http://www.theses.fr/2007AIX30068.
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Ces dernières années, les Oxydes de Phosphine Secondaires se sont révélés être des préligands de choix des métaux de transition. Aujourd’hui, ils sont très utilisés dans diverses transformations, en particulier dans les réactions de couplage. De plus, les premières applications en catalyse asymétrique ont donné des résultats très prometteurs. Dans ce contexte, nous avons synthétisé de nouveaux complexes associant le palladium ou le platine à des OPS. Ces complexes ont catalysé une réaction de cycloaddition [2+1] entre les dérivés bicycliques [2. 2. 1] et les acétyléniques terminaux et ont permis d’accéder à une gamme variée d’alkylidènes cyclopropanes. L’étude en version asymétrique de la réaction a permis d’obtenir le benzylidène cyclopropane avec un excès énantiomérique de 75%. Avec les alcynes terminaux possédant un acétate tertiaire en position propargylique, une réaction tandem combinant une cycloaddition [2+1] et une réaction d’agrandissement catalysée par le palladium, a également été mise au point. Une étude mécanistique de la réaction de cycloaddition [2+1] a été réalisée et, sur la base de nos résultats expérimentaux nous avons proposé un mécanisme faisant intervenir des intermédiaires palladés de degré d’oxydation (II) ou (IV) ainsi q’un vinylidène palladium comme intermédiaire clef. D’une manière générale, les complexes Pt / OPS se sont montrés plus actifs que leurs analogues palladés et ont permis de développer une réaction de cycloaddition [4+2] induite par les éthers propargyliques et une cycloaddition [2+2+1] entre les norbornadiènes substitués et le phénylacétylèneFor the last decades, SPO have emerged as effective preligands for transition metal. To date, these preligands are largely employed in several transformations, and associated to a metal, they proved to be efficient as catalysts in several cross-coupling reactions. Futhermore, the first applications in asymmetric seem to be very promising. In this context, we synthesized news Pd and Pt/ SPO complexes which both catalyzed an unusual [2+1] cycloaddition of norbonene derivatives with terminal alkynes to afford various functionalized alkylidenecyclopropanes. The asymmetric version of this reaction using chiral SPO afforded benzylidenecyclopropane with 75% e. E. With alkynes containing a tertiary acetate at the propargylic position, a tandem [2+1] cycloaddition / ring expansion reaction was developed. Mechanistic investigations of the [2+1] cycloaddition reaction allowed us to propose a vinylidene intermediate as key intermediate in the catalytic process. Pt / OPS complexes show higher activity compared to Pd complexes catalyzing a [4+2] cycloaddition between alkylidene cyclopropane and terminal alkynes. The Pt complex revealed appeared to be an efficient catalyst for the [2+2+1] cycloaddition when C7-substituted norbornadiene were used
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Getty, April D. "Syntheses and reactivity studies of hydroxo-palladium(II) and amido-platinum(IV) complexes /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/8653.
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Touma, Marwan. "Nouvelles reactions d'oligomerisation et de telomerisation selectives catalysees par des complexes cationiques du palladium." Toulouse 3, 1986. http://www.theses.fr/1986TOU30139.
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Ellul, Charles. "Trimetallic N-heterocyclic carbene complexes." Thesis, University of Bath, 2011. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.538279.
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Soares, Daniel da Costa e. Silva Coelho. "Estudo estrutural de produtos da degradação de [Pd2(C2,N-(dmpa)2(μ-dppf)Cl2]." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/75/75132/tde-17042012-114913/.
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A cristalografia por difração de raios X (DRX) é uma ciência eminentemente interdisciplinar, cujo desenvolvimento tem possibilitado o avanço de várias outras áreas científicas. A determinação das estruturas tridimensionais de substâncias, sejam elas naturais ou sintéticas, tem sido fundamental para o estudo e compreensão das relações entre propriedades físicas, químicas e terapêuticas, e a estrutura a nível atômico. Neste trabalho serão apresentados alguns aspectos teóricos sobre complexos ferrocenos e a teoria envolvida na determinação de estruturas cristalinas e moleculares por DRX, bem como a resolução e caracterização de dois complexos ferrocenos. Os resultados obtidos foram comparados com estruturas similares encontradas no Cambridge Structural Database. Nos compostos estudados no presente trabalho, 1,1\'- bis(difenilfosfina)ferroceno e oCHCl3, o Fe apresentou-se complexado a dois anéis de ciclopentadienila, em conformação estrela, os quais estão dispostos de forma equidistante do átomo de Fe, não apresentando distorções significativas. Devido à alta toxicidade da cis-platina no tratamento de neoplasias, muitos grupos de pesquisa têm dedicado seus esforços a encontrar fármacos análogos compatíveis, sendo os derivados de paládio muito visados por terem propriedades eletrônicas e estruturais semelhantes. Sabe-se que a geometria em torno do átomo de platina, na cis-Pt, é quadrado planar, como no presente caso, o que torna o composto oCHCl3 passível de ser estudado quanto à sua possível atividade. Uma das grandes incógnitas dentro da área de farmacologia é saber exatamente quais são os produtos oriundos da degradação de um determinado fármaco e através da determinação por DRX das estruturas cristalinas e moleculares dos dois compostos estudados, concluiu-se que os mesmos são oriundos da degradação do composto [Pd2(C2, N-(dmpa) 2 (μ-dppf)Cl2], uma vez que os compostos estudados tiveram suas estruturas determinadas a partir de um tubo contendo o composto inicial. Portanto, o presente trabalho possui uma considerável importância no estudo deste fármaco o qual pode ser usado no combate ao câncer.X-ray diffraction is a highly interdisciplinary science, whose development has enabled the advancement of several other scientific areas. The determination of three-dimensional structures of substances, whether natural or synthetic, have been fundamental to the study and understanding of the relationships between physical, chemical, therapeutic and structure at the atomic level. This work will present some theoretical aspects of ferrocene complexes and the theory involved in determining of molecular and crystal structures by XRD, as well as resolution and characterization of two ferrocene complexes. The results were compared with similar structures found in the Cambridge Structural Database. At the compounds studied in the present work, 1,1\'-bis(diphenylphosphine)ferrocene e {(Dichloride)[bis (diphenylphosphine)-ferrocene]Palladium(II)}oCHCl3, the Fe complexes with two cyclopentadyenil rings, at star conformation, which are disposed equidistant from Fe atom, without significant distortions. Due to the elevated toxicity of cis-platine at neoplasms, many research groups have been dedicated efforts to found compatible analog drugs, which the palladium derivatives are the most researched, because of their electronic and structural properties. It has been known that the geometry around the Pt is square planar, as like as the present case, which makes the {(Dichloride)[bis (diphenylphosphine)-ferrocene] Palladium(II)}oCHCl3, possible to be study at his possibly activity. One of the great unknowns in the area of pharmacology is to know exactly which are the products of degradation of a certain drug and determining by XRD the crystal and molecular structures of both studied compounds, concluded that they are derived from the degradation of the compound [Pd2(C2, N-(dmpa) 2 (μ-dppf)Cl2], since such compounds has their structures determined from a tube containing the [Pd2(C2, N-(dmpa) 2 (μ-dppf)Cl2]. So, the present work has considerable importance in the study of this drug which can be used against cancer.
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Cloete, Jezreel. "Synthesis and applications of functionalized pyridinyl imine complexes of palladium." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&.
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The synthesis and characterization of pyridinyl &alpha-diimine Pd(II) complexes having a functionalized hydrocarbon attached to the imino nitrogen was performed. The catalytic activity of these complexes were then evaluated in the polymerization of ethylene and in the Heck coupling reaction of methyl acrylate with iodobenzene.
Unconjugated &beta
-diimine complexes of palladium were also synthesized and their activities towards ethylene polymerization and the Heck coupling of methyl acrylate and iodobenzene also evaluated and compared to that of the &alpha
-diimine complexes. Three of the &alpha
-diimine complexes synthesized showed activity towards ethylene polymerization, these being the complexes bearing the allyl, styrene and phenol functionalities. &omega
-Carboxylato complexes which were also synthesized showed no activity towards ethylene polymerization.
The polymer produced was found to be high density linear polyethylene with an average PDI of 2.54 with Mn values ranging between 3.42 and 6.90 x 10-5 and Mw values ranging between 6.05 and 17.6 x 10-5.
The complexes bearing the allyl, styrene and phenol functionalities, as well as the &omega
-carboxylato complexes active in the Heck coupling reactions of methyl acrylate with iodobenzene. None of the unconjugated &beta
-diimine complexes prepared showed any activity towards ethylene polymerization even at high Al/Pd ratios. The activity of these complexes towards the Heck arylation reaction was comparable to that of the &alpha
-diimine complexes showing similar activities.
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Ackerman, Lily Joy Grubbs Robert H. Bercaw John E. "Ancillary ligand effects in niobocene olefin hydride complexes and hydrocarbon oxidation by palladium(II) complexes /." Diss., Pasadena, Calif. : California Institute of Technology, 2003. http://resolver.caltech.edu/CaltechETD:etd-05212003-130334.
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Heß, David. "Palladium(II) complexes and phenylboronic acid esters of deoxy sugars." Diss., lmu, 2012. http://nbn-resolving.de/urn:nbn:de:bvb:19-151675.
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Mentes, Ayfer. "Synthesis and reactions of allyl complexes of palladium and molybdenum." Thesis, University of Leicester, 1997. http://hdl.handle.net/2381/30008.
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Chapter 2 is a review of the 3-oxodimethylenemethane complexes of transition metals. Several new 3-oxodimethylenemethane palladium complexes with bidentate phosphorus ligands of the type [Pd(3-RCHCOCHR)L2] have been prepared.;Chapter 3 is a description of the synthesis of trans-[PdXPh(SbPh3)2] (X = Cl or Br) complexes prepared by the reaction of SbPh3 with several palladium(II) complexes. These reactions involve a novel phenyl group transfer from antimony to palladium. The SbPh3 ligands in these complexes can be displaced by phosphorus and nitrogen donor ligands to prepare convenient syntheses of a variety of palladium(II) complexes. The crystal structures of the complexes [PdXPhL2] (L = SbPh3, X = Cl or Br; L = PPh3, X = Cl; L2 = bipy, X = Cl) and [PdXPhL2]2 (L2 = dppm, X = Cl or Br) are described.;Chapter 4 is a description of the synthesis and characterisation of molybdenum and tungsten tetracarbonyl complexes of pyridyl amine Schiff base ligands of the type [M(CO)4(NN)] (M = Mo or W). These complexes have been prepared by the reaction of cis-[M(CO)4(pip)2] with the Schiff base ligands. The crystal structures of the [Mo(CO)4[N(Me)=C(Me)C5H4N}] and [Mo(CO)4{N(Me)=C(Ph)C5H4N}] are described.;Chapter 5 is a description of the synthesis and reactivity of 3-allyl complexes of molybdenum of the type [MoCl(CO)2(NN)(3-allyl)] prepared by the reaction of allyl halides with [MO(CO)4(NN)] complexes. Treatment of [Mo(CO)4(NN)] complexes with [Pd2Cl2allyl2] also provides a route to these complexes. The crystal structures of two complexes [MoCl(CO)2{N(C6H4OMe)=C(Ph)C5H4N}(3-C3H5)] and [MoCl(CO)2{N(Me)=C(Ph)C5H4N}(3-C3H5)] are described. Attempts to synthesise hydroxy allyl complexes of molybdenum by hydroxy allyl transfer reactions with the palladium complex [PdCl(3-RCHCOHCHR)]2 were unsuccessful.
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Christmann, Ute. "Dinuclear palladium complexes : synthesis, reactivity and their application in catalysis." Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.435512.
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Titcomb, Lisa Rae. "Novel palladium N-heterocyclic carbene complexes as catalysts for aminations." Thesis, University of Sussex, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395012.
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The work described in this thesis is primarily focused on the synthesis and characterisation of two-coordinate zerovalent palladium complexes bearing an N-heterocyclic carbene ligand. These complexes have been assessed as pre-catalysts for coupling reactions in particular ami nation reactions involving the generation of a C-N bond. Chapter 1 presents the synthesis of complexes r, r bearing the ligand [CNCBu)(CH)2NCBu)]. An alternative synthesis for [Pd{CNCBu)(CH)2NCBu)h] 1 is reported involving reaction of [{Pd(T)3-C4H7)Clhl with sodium dimethyl malonate and carbene. Reaction of 1 with iodobenzene led to formation of a Pd(II) speCies, r , [Pd{CNCBu)(CHhNCBu)h(C6Hs)I] 2. An intermediate in the synthesis of 1, r [Pd(T)3-C4H7){CNCBu)(CHhNCBu)h(C6Hs)C] 3, has been isolated and fully characterised. Two r , mixed carbene phosphine complexes, [Pd{CNCBu)(CHhNCBu)}{P(o-tolylh}] 4 and r , [Pd{CNCBu)(CHhNCBu)} {PCY3} 1 S, have also been synthesised. Complexes 1,4 and S have been assessed as a pre-catalysts for ami nation couplings with limited success. Chapter 3 presents the r , synthesis of two complexes bearing the ligand [CN(Me)(CMe)2N(Me)]. Metal vapour synthesis was r , used to synthesise [Pd{CN(Me)(CMehN(Me)h] 6 and the diiodide complex r , [Pd{CN(Me)(CMehN(Me)hI2] 7 was also prepared. Complexes 6 and 7 were shown to have no activity as pre-catalysts in amination couplings. Chapter 4 presents the synthesis of complexes r· ~. bearing the ligand [CN(2,6-'Pr2-C6H3)(CH2hN(2,6-'PrrC6H3)]. The methodology used to synthesise r. ~. 1 was applied to the synthesis of [Pd{CN(2,6-'Pr2-C6H3)(CH2hN(2,6-'PrrC6H3)h] 8. Substitution of a phosphine ligand In [Pd {P(o-tolylh hl by carbene led to formation of r. ~. [Pd{CN(2,6-'PrrC6H3)(CH2hN(2,6-'PrrC6H3)}{P(o-tolyl)3}] 9. Complexes 8 and 9 were successfully employed as pre-catalysts for amination couplings. 4-Chlorotoluene was shown to couple to a variety of primary and secondary amines including cyclic, acyclic and aryl substituted as well as an imine. The same proceedure was also used to couple chloropyridines with morpho line Reactions were typically conducted with 2 mol% pre-catalyst and KOtBu base in dioxane at 100 °C and were found to be complete after 0.5-5 h. The isolated yields of product obtained were typically r· ~. above 95%. Reaction of 1 with [CN(2,6-'Pr2-C6H3)(CH2hN(2,6-'Pr2-C6H3)] led to formation of r \ r. ~. [Pd{CN(,Bu)(CH)2N(,Bu)} {CN(2,6-'Pr2-C6H3)(CH2hN(2,6-'Pr2-C6H3)}] 10. Complex 10 was found to be less active as a pre-catalyst for amination couplings than either 8 or 9. A copper carbene r. ~. complex [Cu {CN(2,6-'Pr2-C6H3)(CH2)2N(2,6-'Pr2-C6H3)} I] 11 was also synthesised and shown to facilitate the coupling of 4-iodotoluene with morpholine to give the coupled product in a 38% yield. Chapter 5 presents the results of some ligand substitution reactions. Complexes 1 and 8 were reacted with phosphines to give mixed carbene phosphine complexes 4, S and 9. The results obtained showed that phosphines can displace carbenes despite the strength of metal carbene bonds
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Van, Wyk Shane Cedrick. "Some new bimetallic nickel and palladium complexes for catalysis applications." University of the Western Cape, 2015. http://hdl.handle.net/11394/4873.
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>Magister Scientiae - MScThis thesis reports on the syntheses of new bimetallic iminopyridyl nickel(II) and palladium(II) complexes as catalyst precursors for ethylene ligomerization/polymerization. Tetrahydrophenyl-linked iminopyridyl ligands, pyridin-2-ylmethyl-{4-[(pyridin-2-ylmethylimino)-methyl]-benzylidene}-amine (L1) and (2-pyridin-2-yl-ethyl)-{4-[(2-pyridin-2-yl-ethylimino)-methyl]-benzylidene}-amine (L2) were prepared via condensation from terephthaldehyde and 2 molar equivalents of a primary pyridylamine. Alkyl-linked iminopyridyl ligands N,N'-bis-pyridin-2-ylmethylene-propane-1,3-diamine (L3), N,N'-bispyridin- 2-ylmethylene-butane-1,4-diamine (L4) and N,N'-bis-pyridin-2-ylmethylenepentane- 1,5-diamine (L5) were prepared by condensation of 2 equivalents of 2- pyridinecarboxaldehyde and a primary diamine. The ligands were obtained as either red oils or orange solids. These ligands were characterized using Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), mass spectrometry (MS), elemental analysis (EA), ultraviolet-visible spectrophotometry (UV-Vis) and thermal gravimetric analysis (TGA) where applicable. The tetrahydrophenyl-linked iminopyridyl ligands were subsequently used to prepare their corresponding homobimetallic palladium(II) and nickel(II) complexes. A 1:2 reaction of the ligands with PdCl2(COD), NiCl2(DME) and NiBr2(DME) gave palladium(II) and nickel(II) complexes C1-C6 in moderate to very good yields (58-94%). The palladium(II) complexes were found to be stable, but light-sensitive solids while the nickel(II) complexes were found to be stable, but light and air sensitive solids. These complexes were characterized using FTIR, NMR, EA, MS, UV-Vis and TGA. These complexes were then tested for catalytic activity of ethylene oligomerization. It was found that complexes C1 and C5 were highly active when activated by the cocatalysts methylaluminoxane (MAO) as well as ethyl aluminium dichloride (EADC). It was found that EADC gave the highest activity so the remaining catalysts (C3 and C6) were tested exclusively with EADC. All four complexes were active for ethylene oligomerization with yields of between 2.7-6.5 g, with C5 providing the highest activity and C1 the lowest. These catalysts were highly selective towards C4 oligomers with percentages ranging from 71-81%. Optimization studies were then carried out with C3 by varying the pressure and Al:Ni ratio.
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Mahamo, Tebello. "Iminophosphine complexes of palladium and platinum: catalysis and metallacycloalkanes synthesis." Doctoral thesis, University of Cape Town, 2012. http://hdl.handle.net/11427/6890.
Full textAbstract:
A series of N-functionalized 2-diphenylphosphinobenzaldimino ligands (3.1 â 3.6) bearing pendant groups on the imine moiety were prepared by the Schiff-base condensation reaction of 2-diphenylphosphinibenzaldehyde and appropriate primary amines. The ligands were subsequently used to synthesize a range of palladium complexes of the types [Pd(P^N)Cl2] (3.7 â 3.12) and [Pd(P^N)(Me)Cl)] (3.13 â 3.18) from precursor complexes [Pd(COD)Cl2] and [Pd(COD)(Me)Cl], respectively. Platinum complexes of the type [Pt(P^N)Cl2] (3.19 â 3.24) were synthesized by the ligand displacement reaction between [Pt(COD)Cl2] and ligands 3.1 â 3.6. All compounds were characterized by multinuclear NMR and infrared spectroscopies as well as elemental analysis. In addition, the structure of complex 3.14 was determined by x-ray crystallography. Palladium complexes 3.8 â 3.10 and 3.16 were evaluated as pre-catalysts in the Suzuki- Miyaura coupling reaction. These complexes were found to be highly active and tolerant of a wide range of reaction conditions and functional groups on substrates. Low catalyst loadings (0.1 mol% Pd) were required, while high conversions and short reaction times were maintained. Having a substituent bearing a donor atom on the imine moiety of the ligand (ligands 3.3 and 3.4) was found to enhance catalytic activity. Palladium methyl chloride complexes were found to show slightly more activity than their palladium dichloride counterparts. Reaction of [Pt(P^N)Cl2] complexes with BrMg(CH2)4MgBr in an attempt to synthesize platinacycloalkane complexes resulted in the formation of bromobutyl complexes [Pt(P^N)(C4H9)Br] (3.25 and 3.26) instead. Successful synthesis of platinacyclopentane complexes, 5.1 â 5.6, and platinacycloheptane complexes, 5.7 â 5.12, was achieved by the reaction of [Pt(COD)Cl2] with appropriate di-Grignard reagents, followed by ligand displacement with the iminophosphine ligands. All complexes were fully characterized using various NMR spectroscopies, mass spectrometry and elemental analysis. Crystal structures of the bromobutyl and platinacyclopentane complexes 3.25 and 5.1 were determined. Studies on the thermal decomposition of the platinacycloalkane complexes were carried out. Platinacyclopentane complexes 5.1 â 5.6 were found to be markedly stable, with the decomposition reaction requiring temperatures higher than 100 °C. Reaction temperature and duration were found to have a significant influence on the organic product distribution obtained. These reactions gave 1-butene (for the platinacyclopentane complexes) and 1- hexene (for the platinacycloheptane complexes) as major products. Kinetic data obtained for the decomposition of 5.1 and 5.7 shows that the decomposition reaction follows first order kinetics for the initial 30% of the decomposition reaction. Thereafter, reaction order deviates from first order behaviour, indicating increasing involvement of products in the reaction mechanism. The generally accepted β-hydride elimination/reductive elimination reaction mechanism for the decomposition of metallacycloalkanes was investigated using DFT methods. The simplified complex, 5.13B, was used as a model for platinacyclopentane complexes. Results from these calculations show that intramolecular β-hydride elimination from the carbocyclic ring of platinacyclopentane complexes is unlikely to occur as this process requires an extremely high energy barrier (>64 kcal.mol-1). Furthermore, these calculations reveal that ligand hemilability is energetically disfavoured in the β-elimination reaction while it is favoured in the reductive elimination reaction.
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Hobart, David B. Jr. "Synthesis, Structural, and Catalytic Studies of Palladium Amino Acid Complexes." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/79719.
Full textAbstract:
Palladium(II) acetate and palladium(II) chloride react with amino acids in acetone/water to yield cis or trans square planar bis-chelated palladium amino acid complexes. The naturally occurring amino acids and some N-alkylated and substituted derivatives and homologs were evaluated as ligands. Thirty-eight amino acids in total were investigated as ligands. The formation of aquo complexes in water was observed and studied by 13C NMR spectroscopy and modeled by DFT calculations. Each class of amino acid ligand is catalytically active with respect to the oxidative coupling of olefins and phenylboronic acids. Some enantioselectivity is observed and the formation of products not reported in other Pd(II) oxidative couplings is seen. Both activated and non-activated alkenes were oxidatively coupled to phenylboronic acids incorporating both electron-donating and electron-withdrawing groups. The crystal structures of nineteen catalyst complexes were obtained. The extended lattice structures arise from N-H..O or O..(HOH)..O hydrogen bonding. NMR, HRMS, FTIR, single crystal XRD, and powder XRD data are evaluated.Ph. D.
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Pekar, Jennifer Christina. "The Gas-Phase Ligand Exchange of Palladium Beta-diketonate Complexes." Youngstown State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1410910663.
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Adhikary, Anubendu. "Synthesis and Catalytic Applications of Nickel and Palladium Pincer Complexes." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1439281406.
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