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Taylor, Peter Neil. „Synthesis and study of medium-ring diphosphines“. Thesis, University of Bristol, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319096.
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Long, James Maurice. „Synthesis of new axially chiral diphosphines and phosphinamines for asymmetric catalysis“. Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337600.
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Woodworth, Patrick. „Synthesis and Analysis of Gold Nanoclusters“. VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5569.
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Gold Nanoclusters are of particular interest due to their many possible applications across a wide range of scientific fields. More specifically, nano-sized gold particles have potential to be used in drug delivery systems, cancer therapy and catalysis. This dissertation focuses on improving our understanding of ligated gold nanoclusters by examining the role of a variety of phosphine based ligands, novel methods to produce monodisperse solutions, and investigating the kinetics of water soluble ligated gold nanoclusters.
The addition of ligands to solutions of Au have shown to produce small (< 20 Au atoms) clusters. All nanocluster solutions were prepared in a similar manner. Typically, a gold salt, either Chloro(triphenylphosphine) gold(I) (Au(PPh3)Cl), or Potassium gold (III) chloride (KAuCl4), were dissolved in various solvents. Next, an equal concentration of ligand was added to the solution and stirred until completely dissolved. Finally, all were reduced with 5X the concentration of borane-tert-butylamine (BTBC) after which were sonicated for ~20 minutes. The timing and method of adding the ligands and reducing agent varied depending on the solution and solubility of the ligands.
Primarily we used Electrospray Ionization Mass Spectrometry (ESI-MS) and Ultraviolet – Visible Spectroscopy (UV-VIS) for the characterization of samples, however, occasionally Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD) and X-Ray Photoemission Spectroscopy (XPS) were used. The most recent research took advantage of the size selective nature of an alpha hemolysin (a-HL) nanopore to investigate the kinetics of thiol-ligated Au clusters ~2 nm in size.
The relationship between ligand rigidity and solvent polarity and the size and dispersity of Au cluster suspensions was investigated. We observed the formation of stable monodisperse clusters with the shortest ligand, (L3), independent of solvent. With a longer flexible ligand, (L6), we observed primarily Au8-10 cores depending on the ratio of L6/PPh3. All other ligands yielded polydisperse distributions. These dispersions contained clusters with a nuclearity between 8 and 11, for example [Au10(PPh3)9]3+ in LBn and [Au8(PPh3)7]2+ in LBp, were observed in the initial stages, but they were not stable and precipitated out or plated the glass vial. We also observed that the polarity of the solvent did not play a significant role in the formation of MPC’s, however a correlation between the size of the solvent and MPC formation was observed.
The growth and evolution of two unique gold structures was also observed via UV-Vis and ESI-MS. Solutions were prepared which contained Potassium gold (III) chloride and PPh2(CH2)3PPh2, i.e., 1,3-bis(diphenylphosphino)propane, denoted by L3, reduced with Borane tert-butylamine complex (BTBC) in a 1:1 diethyl ether:methanol mix, which yielded a stable [Au11(L3)5]+3. Starting with this known Au11 solution, the addition of Mn2+ has shown to lead to the formation of a stable diphosphine ligated Au8 and a new Au14 species.
Additionally, we show that the co-reduction of NiCl2 and Au in the absence of the ligand (L3) does give us a simple method for the production of a monodisperse [Au9(PPh3)8]2+ cluster solution and via electroless deposition does give us a potential low temperature pathway to the formation of a AuNi nanoalloy particle.
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Leonard, Thomas Ralph. „New diphosphanes and their application in the synthesis of rigid backboned diphosphines“. Thesis, University of Bristol, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.529843.
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Lam, Tun Chiao Hubert. „Synthesis of chiral amino (amido) diphosphines and applications in palladium catalyzed asymmetric processes“. Thesis, King's College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398250.
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Ekanayake, Dewmi A. „Copper Hydride Clusters Stabilized by NH-Centered Diphosphines: Synthesis, Structures, and Implications in Catalysis“. University of Cincinnati / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1626356614867446.
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Marsh, Paul Samuel. „Synthesis, characterisation and precious metal chemistry of symmetrical and unsymmetrical diphosphines based on 9-phosphabicyclononanes“. Thesis, University of Bristol, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289719.
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Zwart, Guilhem. „Hydrogénolyse de (pseudo-)haloboranes et de chlorophosphines“. Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASF049.
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Cette thèse examine les défis posés par l’accès incertain aux éléments chimiques, exacerbée par un paradigme économique linéaire de leur exploitation. L’étude se concentre sur le bore et le phosphore, dont l’utilisation et le recyclage restent sous-étudiés. Le bore, crucial dans diverses industries, nécessite des processus énergivores pour être transformé en hydroboranes actifs, utilisés en chimie fine. Deux voies existent pour leur synthèse : la méthode industrielle à partir de borate, et la réaction de BCl₃ avec un donneur d’hydrure. Utiliser H₂ comme agent réducteur pourrait améliorer ces processus. Cette recherche explore la synthèse d’hydroboranes [9-BBN]₂ et [Cy₂BH]₂ à partir de leurs dérivés halogénés et triflate, avec une base et H₂. Le criblage des bases a montré que les trialkylamines, surtout NEt₃, sont efficaces. La réaction repose sur un mécanisme type paire de Lewis frustrée pour activer le H₂. Il s’avère également que les dialkylboranes peuvent catalyser l’hydrogénolyse d’autres chloroboranes, en particulier de BCl₃, permettant d’obtenir HCl₂B·NEt₃ et H₂ClB · NEt₃. Enfin, cette stratégie a été étendue au phosphore, optimisant l’hydrogénolyse des chlorophosphines en diphosphines. La méthode, efficace pour divers substrats, procède en trois étapes : hydrogénolyse du catalyseur, transfert d’hydrure, et condensation en diphosphine, assistée par NEt₃. Ces transformations ont été modélisées chaque fois par théorie de la fonctionnelle de la densité (DFT) et présentent des temps de réactions souvent longs (jusqu’à plusieurs jours), mais avec en général de bons rendements (> 70 %) en conditions douces de pression et températureThis thesis examines the challenges posed by uncertain access to chemical elements, exacerbated by a linear economic paradigm of their exploitation. The study focuses on boron and phosphorus, whose usage and recycling remain understudied. Boron, crucial in various industries, requires energy-intensive processes to be converted into active hydroboranes, used in fine chemistry. Two methods exist for their synthesis: the industrial method from borate, and the reaction of BCl₃ with a hydride donor. Using H₂ as a reducing agent could improve these processes. This research explores the synthesis of hydroboranes [9-BBN]₂ and [Cy₂BH]₂ from their halogenated and triflate derivatives, with a base and H₂. Base screening showed that trialkylamines, particularly NEt₃, are effective. The reaction relies on a frustrated Lewis pair mechanism to activate H₂. It was also found that dialkylboranes can catalyze the hydrogenolysis of other chloroboranes, particularly BCl₃, yielding HCl₂B· NEt₃ and H₂ClB·NEt₃. Finally, this strategy was extended to phosphorus, optimizing the hydrogenolysis of chlorophosphines into diphosphines. The method, effective for various substrates, proceeds in three steps : catalyst hydrogenolysis, hydride transfer, and base-assisted condensation into diphosphine. These transformations were modeled each time using density functional theory (DFT) and often present long reaction times (up to several days), but usually with good yields (> 70 %) under mild pressure and temperature conditions
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Gramage-Doria, Rafael. „Large cavity cyclodextrin-based macrocyclic ligands : synthesis, coordination and catalytic properties“. Phd thesis, Université de Strasbourg, 2012. http://tel.archives-ouvertes.fr/tel-00767168.
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Cyclodextrins (CDs) are cyclic oligosaccharides of various sizes containing several α-(1→4)-linked D-(+)- glucopyranose units. The commercially available ones comprise six, seven or eight glucose units, named respectively α-CD, β-CD and γ-CD. Their truncated cone-like and well-defined cavity are particularly attractive for the encapsulation of a variety of substrates. As such, they found numerous applications in many areas of chemistry. A recent development, from which the present work is inspired, consisted in covalently linking transition metals to CD cavities in order to perform and study catalytic reactions in a confined environment featuring steric repulsive or attractive noncovalent interactions with the substrate or/and the metal coordination sphere.The first part of this thesis focuses on reviewing transition metal-based cavitands, for which the first and second metal coordination spheres are controlled by their cavity-shaped ligand. The following chapters are concerned with the synthesis, coordination and catalytic properties of two new phosphane ligands built on a large β-CD scaffold. The first one, named WIDEPHOS, is a diphosphine having two phenylphosphinidene "PPh" units capping adjacent glucose units on a methylated β-CD. This ligand features two phosphorus lone pairs pointing to the cavity interior but not aligned. These geometrical features, combined with the large distance separating the two phosphorus atoms, promote the formation of "imperfect" trans-chelate complexes in which the metal centre swings about the ligand. This unprecedented molecular movement, christened "oschelation", allows each phosphorus atom to form an optimal bond in turn with the coordinated d8 and d10 transition metal ions. Further studies on WIDEPHOS proved that it is better suited for coordinating dinuclear fragments within the confinement of the large β-CD cavity. Severe steric constrains on the metal first sphere of coordination result in the formation of single μ-chlorido bridged dinuclear species. In this new type of square planar complexes, non-optimal orbital overlapping measured by the so-called tilt angle was also found to take place for one of the phosphorus atom together with an "oschelation" movement involving non identical donor atoms, namely a phosphorus and an oxygen atom. Static gold(I) dinuclear complexes displaying similar imperfect orbital overlapping for one of the phosphorus atom were also prepared.
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Fiedler, Tobias [Verfasser], und John A. [Akademischer Betreuer] Gladysz. „Syntheses of Gyroscope-like Osmium Complexes and Cage-like Diphosphines = Synthese gyroskopartiger Osmiumkomplexe und käfigartiger Diphosphine / Tobias Fiedler. Betreuer: John A. Gladysz“. Erlangen : Universitätsbibliothek der Universität Erlangen-Nürnberg, 2011. http://d-nb.info/1015475116/34.
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Salomon, Christine. „Nouvelle synthèse stéréosélective de diphosphines à pont méthano P-stéréogéniques : applications en catalyse asymétrique et pour la préparation de clusters ou de polymères de coordination chiraux“. Thesis, Dijon, 2010. http://www.theses.fr/2010DIJOS010/document.
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Ce mémoire porte sur la synthèse asymétrique de ligands à pont méthano P-stéréogénique, ainsi que sur leurs applications en catalyse asymétrique, en chimie de coordination et pour la préparation de polymères de coordination avec des métaux de transition. Les diphosphines P-stéréogéniques sont synthétisées par création d'une liaison phosphore-carbone au niveau du pont méthano, à partir d'un anion formé en position α d'une méthylphosphines borane. Plusieurs stratégies ont été étudiées selon que l'électrophile est un complexe d’oxazaphospholidine borane, un phosphinite borane ou une chlorophosphine borane. L'utilisation de chlorophosphine borane dans cette synthèse s'est révélée la plus stéréosélective car les excès énantiomériques obtenus sont supérieurs à 99%. Les différentes stratégies étudiées montrent qu'il est possible d’accéder à des diphosphines diborane à pont méthano variées, dissymétriques ou de symétrie C2, porteuses de substituants alkyl ou aryl, tels que Me, OMe, Ph, o-An... Les diphosphines P-stéréogéniques obtenues ont été utilisées pour la synthèse des premiers clusters chiraux du palladium. Ceux-ci sont obtenus par réaction des ligands diphosphines, fraîchement décomplexées avec du DABCO, avec l’acétate de palladium en présence d’acide trifluoroacétique dans un mélange eau/acétone sous pression de CO. La structure cristallographique d'un des clusters de palladium préparés a pu être établie, confirmant la structure avec un cœur trimétallique de palladium. L'étude des propriétés électrochimiques et l'analyse RPE de ces clusters a permis de mettre en évidence la formation du premier radical dans un environnement chiral hautement structuré. Une étude de la réactivité de ces clusters chiraux dans une réaction de Friedel Craft a été réalisée, mais le produit est obtenu de façon non catalytique et sans activité optique significative. Par contre dans le cas de réactions asymétriques, tels que l’hydrogénation, l’hydrosilylation, l’allylation ou la réaction de Diels Alder, catalysées par des complexes du rhodium, du palladium ou d’argent, des inductions asymétriques de 30-38% sont obtenus. Il ressort que les synthèses stéréosélectives mises au point dans ce travail, permettent d'envisager maintenant les modifications structurales nécessaires à l'optimisation de ces catalyses asymétriques. Enfin dans une dernière partie, les diphosphines à pont méthano P-stéréogéniques ont été utilisées pour la préparation d'une nouvelle classe de polymères de coordination chiraux, dérivés du cuivre ou de l'argent. Les études photophysiques et le dichroïsme circulaire ont permis d’établir pour la première fois la structure 1-D de tels polymères et de mettre en évidence les propriétés optiques des macrocomplexes énantiomèresWe were interested in asymmetric synthesis of P-stereogenic methano bridged ligands and in their applications in asymmetric catalysis, coordination chemistry and in the preparation of coordination polymers of transition metals. P-stereogenic diphosphines were obtained highly stereoselectively by creation of a phosphorus-carbon bond on the methano bridge, starting from the anion formed in α position of methylphosphine borane. Several strategies were investigated, with the electrophiles varying from oxazaphospholidine borane complex, phosphinite borane, to chlorophosphine borane. The most stereoselective synthesis was obtained using chlorophosphine borane leading enantiomeric excesses up to 99%. Various methano bridge diphosphine diboranes, dissymmetric or C2-symmetric, bearing alkyl or aryl substituants (Me, OMe, Ph, o-An...), have been synthetised. The first chiral palladium clusters was prepared by reaction of the freshly decomplexed diphosphine with palladium acetate and trifluorocetic acid in water/acetone mixture under CO pressure. The palladium trimetallic center structure of the cluster was confirmed by X-ray analysis. Electrochemical properties and EPR analysis pointed out the formation of the first radical in highly structurated chiral environment. Preliminary studies of the chiral clusters in asymmetric Friedel Craft reaction were carried out, but lead to the product in a non-catalytic way and with no significant optical activity. The prepared chiral ligands were tested in asymmetric catalyzed hydrogenation, hydrosilylation, allylation and Diels Alder reaction using rhodium, palladium and silver derived catalysts and afforded low selectivities from 30 to 38% e.e. Nevertheless, the stereoselective syntheses of the diphosphine ligands elaborated in this work allow to pursue the optimisation of asymmetric catalysis by structural modifications. In the last chapter, P-stereogenic methano bridge diphosphines were used for the preparation of a new class of chiral coordination polymers derived from copper and silver. Photophysical studies and circular dichroism confirmed the 1-D structure and the optical properties of such polymers
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Kandala, Srikanth Richmond Michael G. „Synthesis and characterization of diphosphine ligands and diphosphine substituted osmium and ruthenium clusters“. [Denton, Tex.] : University of North Texas, 2007. http://digital.library.unt.edu/permalink/meta-dc-3955.
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STEPHAN, MASSOUD. „Synthese enantioselective de mono et diphosphines tertiaires“. Paris 6, 1991. http://www.theses.fr/1991PA066345.
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Une synthese asymetrique efficace de mono et diphosphines tertiaires ou l'atome de phosphore est porteur de la chiralite est decrite en serie complexee. Son principe repose sur: 1) la separation diastereoselective d'un complexe borane d'oxazaphospholidine derive de l'ephedrine; 2) l'ouverture regio et stereospecifique de l'heterocycle complexe par les organometalliques. L'aminophosphine-borane obtenue est transformee en chlorophosphine ou en phosphinite-borane, respectivement par reaction avec l'acide chlorhydrique ou par methanolyse. Les phosphinites-borane reagissent avec les organolithiens pour conduire aux phosphines-borane avec des e. E. De 85 a 100% et des rendements globaux atteignant 70%. Les methyles phosphines-borane conduisent aux diphosphines-borane par couplage oxydant ou reaction avec un dichlorosilane. Les mono et diphosphines sont isolees quantitativement sans perte de chiralite par decomplexations avec la diethylamine
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Crabtree, Simon Peter. „Synthesis, structure and reaction studies of diphosphine rhodium complexes“. Thesis, Durham University, 1996. http://etheses.dur.ac.uk/5299/.
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A series of complexes of the type [Rh(diphos)(C(_7)H(_8))](BF(_4)) (1) have been synthesised and two of these species [diphos = Bu(^1)(_2)P(CH(_2))(_2)PBu(^1)(_2), Cy(_2)P(l,2-trans-cyclopentane)PCy(_2)] have been characterised by X-ray crystallography. The influence of the chelating diphosphine on the structural characteristics and NMR parameters of these compounds has been investigated. Complexes of the type (1) are active catalysts for the hydroformylation of l-hexene(120ºC, 450psi 2:1 H(_2):C0). However, they are inactive for the related hydroesterification process and this is attributed to the stability of [Rh(diphos)(CO)(_2)]^ under the reaction conditions. Detailed studies of the reactions of type (1) complexes with H(_2) have been undertaken. The products from these reactions are dependent on both the diphosphine and the solvent employed. In THF and CD(_2)Cl(_2), dimeric hydrides were observed, whilst in CDCl(_3) hydrido-chloro-complexes of the type [Rh(_z)(diphos)(_2)(|µCl)H(_2)](^2+) were formed. In the former solvents, three types of hydrides have been identified by NMR studies, namely [Rh(_2)(diphos)(_2)H(_6)], [Rh(_2)(diphos)(_2)H(_4)] and [Rh(_2)(diphos)(_2)H(_4)](^2+). The oxidative-addition reactions of alkyl-, acyl- and formyl-halide with Rh(I) complexes have been investigated. The reaction with ClCO(_2)Me with [Rh(dppe)Cl](_2) and [Rh(dppe)](_2)(BF(_4))(_2) led to the formation of diphosphine-rhodium(III)-halide species (H(_3)NOH)[Rh(dppe)Cl(_4)] and [Rh(_2)(dppe)(_2)(µ-Cl)(_3)Cl(_2)](BF(_4)) respectively. Alternative routes to these complexes have been investigated starting from RhCl(_3).3H(_2)O/diphosphines and a series of the novel halide bridged dimers have been characterised, including by X-ray crystallography and their reaction chemistry explored. In the synthesis of the cationic rhodium complexes from neutral chloro-complexes with AgBF(_4), the novel silver complexes [Ag(_2)(µ-Bu(^t)(_2)P(CH(_2))(_3)PBu(^t)(_2))(_2)](BF(_4))(_2), [{Ag(H(_2)O)}(_2)(µ-Bu(^t)(_2)P(CH(_2))(_2)PBu(^t)(_2))](BF(_4))(_2), and [Ag(C(_6)D(_6))(_3)BF(_4)] have been isolated as by-products and characterised by X-ray crystallography.
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Kandala, Srikanth. „Synthesis and characterization of diphosphine ligand substituted osmium and ruthenium clusters“. Thesis, University of North Texas, 2007. https://digital.library.unt.edu/ark:/67531/metadc3955/.
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The kinetics for the bridge-to-chelate isomerization of the dppe ligand in H4Ru4(CO)10(dppe) have been investigated by UV-vis and NMR spectroscopies over the temperature range of 308-328 K. The isomerization of the ligand-bridged cluster 1,2-H4Ru4(CO)10(dppe) was found to be reversible by 31P NMR spectroscopy, affording a Keq = 15.7 at 323 K in favor of the chelating dppe isomer. The forward (k1) and reverse (k-1) first-order rate constants for the reaction have been measured in different solvents and in the presence of ligand trapping agents (CO and PPh3). On the basis of the activation parameters and reaction rates that are unaffected by added CO and PPh3, a sequence involving the nondissociative migration of a phosphine moiety and two CO groups between basal ruthenium centers is proposed and discussed.
The substitution of the MeCN ligands in the activated cluster 1,2-Os3(CO)10(MeCN)2 by the diphosphine ligands dppbz proceeds rapidly at room temperature to furnish a mixture of bridging and chelating Os3(CO)10(dppbz) isomers and the ortho-metalated product HOs3(CO)9[μ-(PPh2)C=C{PPh(C6H4)}C4H4]. Thermolysis of the bridging isomer 1,2-Os3(CO)10(dppbz) under mild conditions gives the chelating isomer 1,1-Os3(CO)10(dppbz), molecular structure of both the isomers have been determined by X-ray crystallography. The kinetics for the ligand isomerization has been investigated by UV-vis and 1H NMR spectroscopy in toluene solution over the temperature range of 318-343 K. On the basis of kinetic data conducted in the presence of added CO and the Eyring activation parameters, a non-dissociative phosphine migration across one of the Os-Os bonds is proposed. Ortho metalation of one of the phenyl groups associated with the dppbz ligand is triggered by near-UV photolysis of the chelating cluster 1,1-Os3(CO)10(dppbz). The triosmium cluster 1,2-Os3(CO)10(MeCN)2 reacts with the diphosphine ligand 3,4bis(diphenylphosphino)-5-methoxy-2(5)H-furanone (bmf) at 25 ºC to give the bmf-bridged cluster 1,2-Os3(CO)10(bmf). Heating 1,2-Os3(CO)10(bmf) leads to an equilibrium with the chelating isomer 1,1-Os3(CO)10(bmf). The molecular structure of each isomer has been crystallographically determined, and the kinetics for the isomerization has been investigated by UV-vis and 1H NMR spectroscopy. The reversible nature of the diphosphine isomerization has been confirmed by NMR measurements, and the forward (k1) and reverse (k-1) first-order rate constants for the bridge-to-chelate isomerization have been determined. Thermolysis of the SEQ CHAPTER h r 11,1-Os3(CO)10(bmf) cluster (>110 ºC) leads to regiospecific activation of C-H and P-C bonds, producing the hydrido clusters HOs3(CO)9[µ-PPh2C=C{PPh(C6H4)} CH(OMe)OC(O)] and the benzyne clusters HOs3(CO)8(μ3-C6H4)[µ-PPhC=C(PPh2)CH(OMe)OC(O)]. The hydride and benzyne clusters, which exist as a pair of diastereomers, have been fully characterized in solution by IR and NMR spectroscopy, and the molecular structure of one benzyne cluster (major diastereomer) has been determined by X-ray crystallography.
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LE, GOASTER CELINE. „Synthese asymetrique de nouvelles diphosphines fonctionnalisees et de bis-1,3-oxaphospholanes“. Rennes 1, 1997. http://www.theses.fr/1997REN10163.
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Le travail presente dans ce memoire est consacre a la synthese de nouvelles diphosphines optiquement actives, pouvant servir de ligand de metaux de transition dans des reactions de catalyse asymetrique. Dans la premiere partie, nous avons rappele les principaux resultats obtenus recemment dans le domaine des diphosphines optiquement actives et des complexe phosphine-boranes. Dans la deuxieme partie, nous avons decrit la synthese diastereoselective de trois complexes diphosphine-bisboranes fonctionnalises de formule : (2,2-dimethyl-4,5-bis(1-diphenylphosphino-2-methoxycarbonylethyl)-1,3-dioxolane)-bisboranes. Ces diphosphines sont preparees par addition de deux moles de phosphures sur un diene active issu du d-mannitol. L'etude du mecanisme a permis de montrer que l'addition de ces deux phosphures se deroule en deux etapes. Dans la troisieme partie, nous avons mis au point la synthese d'une nouvelle famille de ligands optiquement actifs a structure bis-1,3-oxaphospholane. Deux types de bis-oxaphospholanes ont ete ainsi synthetises : - les complexes 5,5'-bis-(3-phenyl-1,3-oxaphospholane-borane) prepares a partir du tartrate de diethyle. - les complexes (4,5-(3-phenyl-1,3-dioxaphospholan-5,5'-yl)-2,2-dimethyl-1,3-dioxolane)-bisboranes obtenus, via des intermediaires bisulfates, a partir du d-mannitol. Dans la derniere partie, nous avons teste ces diphosphines complexees au rhodium lors de la reaction d'hydrogenation catalytique de l'acide n-acetamidoacrylique. Les bis-1,3-oxaphospholanes ne presente qu'une faible activite en catalyse asymetrique. Il est probable que la trop grande rigidite du ligand s'oppose a la formation d'un complexe cyclique avec le rhodium. Les diphosphines fonctionnelles conduisent a des resultats voisins de ceux de la diop puisque l'induction asymetrique atteint 80% d'exces enantiomerique avec 2,5% de catalyseur. Les resultats obtenus montrent, par ailleurs, que l'inversion d'un seul centre asymetrique du ligand peut avoir un effet important sur la stereoselectivite de la reaction de catalyse asymetrique.
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Fraze, Kendra Eileen. „Synthesis, electrochemistry, and thermodynamics of mononuclear and dinuclear nickel(II) diphosphine complexes“. Connect to online resource, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3273652.
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Newman, C. R. „A new conformationally flexible diphosphine, NUPHOS, synthesis and applications in asymmetric catalysis“. Thesis, Queen's University Belfast, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426656.
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Merdes, Rachid. „Syntheses asymetriques de diphosphines tertiaires chirales et quelques applications a la catalyse homogene“. Paris 6, 1993. http://www.theses.fr/1993PA066428.
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Ce travail porte sur la mise au point de nouvelles syntheses asymetriques de diphosphines ou la chiralite est portee par l'atome de phosphore. Plusieurs voies ont ete etudiees, soit par creation d'une liaison cc ou d'une liaison cp entre deux complexes de methylphosphine borane, ou bien par creation de deux liaisons csi en utilisant un agent de couplage dichlorosilane, ou encore deux liaisons cp en faisant reagir deux equivalents d'un organometallique sur un complexe diphosphinite. Une autre approche a ete exploree, consistant a faire reagir un dianion sur deux equivalents d'organophosphores. Les differentes voies de synthese qui sont developpees dans ce travail permettent la preparation d'un grand nombre de diphosphines tertiaires a 2, 3, 4 et meme 7 chainons, et tout particulierement des dialkyl et diaryl phosphine tertiaires. La synthese de la premiere diphosphine ayant un pont ferrocenyle, ou le phosphore est stereogene est decrite. Un interet remarquable de ces syntheses reside dans la possibilite de preparer les deux enantiomeres d'une diphosphine a partir du meme complexe d'oxazaphospholidine borane de depart. Une etude preliminaire utilisant les ligands prepares, a ete faite en catalyse homogene d'hydrogenation de c=c ou de c=o, et surtout en allylation catalysees respectivement par des complexes du rhodium, du ruthenium et du palladium. Nous avons montre dans le cas de la catalyse par les complexes-allyliques du palladium, que l'utilisation des complexes de phosphine borane pouvait se substituer avantageusement a l'emploi de la phosphine libre
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Paavola, Sari. „Synthesis and characterisation of 1,2-diphosphino-o-carborane metal complexes“. Helsinki : University of Helsinki, 2002. http://ethesis.helsinki.fi/julkaisut/mat/kemia/vk/paavola/.
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MICHAUD, GUILLAUME. „Synthese de nouvelles diphosphines atropoisomeres dissymetriques caracteristiques et evaluation en hydrogenation asymetrique“. Paris 6, 2001. http://www.theses.fr/2001PA066340.
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L'objet de ce travail a ete la synthese de nouvelles diphosphines atropoisomeres pour des applications en catalyse enantioselective. Dans une premiere partie, nous nous sommes interesses a la synthese d'une diphosphine derivee du motif biphenanthrene. Nous n'avons pu preparer la molecule cible, le 10,10'-diphenylphosphino-9,9'-biphenanthrene : l'encombrement de la position 10 du biphenanthrene etant tres important, sa faible reactivite empeche l'introduction des groupements diphenylphosphino. Dans une seconde partie, nous avons defini une approche originale et generale a de nouvelles diphosphines atropoisomeres, caracterisees par l'absence de symetrie c 2 dans le squelette biaryle. Le motif biaryle non symetrique, optiquement pur, est obtenu par un couplage intramoleculaire diastereoselectif entre deux cycles aromatiques relies par une agrafe chirale. Cette methode nous a permis d'acceder a des diphosphines de structure, et donc de proprietes geometriques, differentes : la meo-naphephos, la trime-naphephos et la trimemeo-biphephos. L'efficacite de ces disphosphines dans des reactions modeles d'hydrogenation catalytique a confirme leur potentiel en catalyse asymetrique. De plus nous avons realise une etude de modelisation moleculaire qui nous donne, en premiere approximation, la valeur des angles diedres entre les cycles aromatiques des ligands trivalents et de leurs complexes de ruthenium. L'etude de l'hydrogenation asymetrique de substrats choisis, dans des conditions rigoureusement controlees, devra permettre de verifier s'il existe ou non, une correlation entre la valeur de l'angle diedre de ces ligands et leur stereoselectivite.
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La, PenseÌe Annemarie Agnes. „Homoleptic diarsine and diphosphine complexes of iron(II), ruthenium(II) and rhodium(III) : synthesis and electrochemistry“. Thesis, University of Liverpool, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250371.
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Supplee, Carolyn. „Synthesis and characterization of bimetallic palladium and platinum complexes resulting from chelating tertiary/secondary diphosphine ligands /“. The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487599963591294.
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Almotawa, Ruaa Mohammed. „Silver(I) and Copper(I) Complexes from Homoleptic to Heteroleptic: Synthesis, Structure and Characterization“. Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1404512/.
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A plethora of novel scientific phenomena and practical applications, such as solid-state molecular solar cells and other optoelectronic devices for energy harvesting and lighting technologies, have catalyzed us to synthesize novel compounds with tunable properties. Synthetic routes, single crystal structures, and spectral and materials properties are described. Reactions of Ag(I) and Cu(I) precursors with various types of ligands -- including the azolates, diimines, and diiphosphines -- lead to the corresponding complexes in high yield. Varying the metal ions, ligands, synthetic methods, solvents, and/or stoichiometric ratio can change the properties including the molecular geometry or packing structure, reactivity, photophysical and photochemical properties, semiconducting behavior, and/or porosity of the functional coordination polymers obtained. For solar cells purposes, the absorption energy can be extended from the ultraviolet (UV) region, through the entire visible (Vis) region, onto a significant portion of the near-infrared (NIR) portion of the solar spectrum with high absorption coefficients due to the infinite conjugation of Cu(I) with diimine ligands. Twenty-eight crystal structures were obtained by conventional crystal growth methods from organic solvents, whereas their bulk product syntheses also included "green chemistry" approaches that precluded the use of hazardous organic solvents. The resulting products are characterized by powder x-ray diffraction (PXRD), Fouriertransform infrared (FTIR), nuclear magnetic resonance (NMR), UV/Vis/NIR absorption/diffuse reflectance/photoluminescence spectroscopies, and thermogravimetric analysis (TGA). Regarding the scientific phenomena investigated, the highlighting work in this dissertation is the discovery of novel bonding/photophysical/optoelectronic properties of the following materials: a black absorber with absorption from 200- 900 nm, a very stable compound with a bright green luminescence obtained by a solventless reaction, and a novel coordination polymer showing uncommon interaction of Ag(I) with three different types of diimine ligands simultaneously.
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Tang, Pui-ling, und 鄧佩玲. „Synthesis, luminescence and host-guest chemistry of mono- and dinuclear platinum(II) complexes of pyridyl and diphosphine ligands“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31243654.
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Tang, Pui-ling. „Synthesis, luminescence and host-guest chemistry of mono- and dinuclear platinum(II) complexes of pyridyl and diphosphine ligands /“. Hong Kong : University of Hong Kong, 2002. http://sunzi.lib.hku.hk/hkuto/record.jsp?B25155040.
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Crosman, George Adrian. „Immobilization of Rh-diphosphine complexes on mesostructured materials and their application to asymmetric hydrogenation and hydroboration“. Aachen Shaker, 2009. http://d-nb.info/999464981/04.
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Nyamwihura, Rogers. „Synthesis of Gold Complexes From Diphosphine Ligands and Screening Reactions of Heterocyclic Acetylacetonato (ACAC) Ligands with Transitional Metal Complexes“. Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc804890/.
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Syntheses of diphosphine gold (I) complexes from gold THT and two ligands, 4, 5-bis (diphenylphosphino)-4-cyclopenten-1, 3-dione (BPCD) and 2,3-bis(diphenylphosphino)-N-phenylmaleimide (BPPM), were done separately. The reactions happened under ice conditions followed by room temperature conditions and produced two diphosphine gold (I) complexes in moderated yield. Spectroscopic results including nuclear magnetic resonance (NMR) and X-ray crystallography were used to study and determine the structures of the products formed. Moreover, X-rays of all newly synthesized diphosphine gold (I) complexes were compared with the known X-ray structures of other phosphine and diphosphine gold (I) complexes. There were direct resemblances in terms of bond length and angle between these new diphosphine gold (I) complex structures and those already published. For instance, the bond lengths and angles from the newly prepared diphosphine gold (I) complexes were similar to those already published. Where there were some deviations in bond angles and length between the newly synthesized structures and those already published, appropriate explanation was given to explain the deviation. Heterocyclic ligands bearing acetylacetonate (ACAC) side arm(s) were prepared from ethyl malonyl chloride and the heterocyclic compounds 8-hydroxylquinoline, Syn-2-peridoxyaldoxime, quinoxalinol and 2, 6-dipyridinylmethanol. The products (heterocyclic ACAC ligands) from these reactions were screened with transition metal carbonyl compounds in thermolytic reactions. The complexes formed were studied and investigated using NMR and X-ray crystallography. Furthermore, the X-ray structures of the heterocyclic ACAC ligand or ligand A and that of rhenium complex 1 were compared with similar published X-ray structures. The comparison showed there were some similarities in terms of bond length and bond angles.
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Koner, Abhishek [Verfasser]. „On the imidazole-2-thione-based route to tricyclic 1,4-diphosphinines: synthesis, structures and reactions / Abhishek Koner“. Bonn : Universitäts- und Landesbibliothek Bonn, 2018. http://d-nb.info/1154485862/34.
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Sivakumar, V. „Influence Of The Bite Angles Of Chelating Diphosphine Ligands In The Chemistry Of Ruthenium Hydride And Dihydrogen Complexes“. Thesis, Indian Institute of Science, 2006. https://etd.iisc.ac.in/handle/2005/293.
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The bite angle of a diphosphine ligand plays an important role in determining the reactivity of a transition metal complex. The coordinated dihydrogen on a transition metal center can be activated toward homolysis or heterolysis depending upon the nature of the metal center and the ancillary ligand environment. The present work deals with our investigations on the effect of the bite angle of the chelating diphosphine ligands in the chemistry of certain ruthenium hydride and dihydrogen complexes.
Protonation of the ds-[Ru(H)2(dppm)(PPh3)2] (dppm = Ph2PCH2PPh2) using HBF4-Et2O resulted in the dihydrogen/hydride complex trans-(Formula). This species shows dynamic exchange of the H-atom between the dihydrogen and the hydride ligands. The H-atom site exchange was studied by NMR spectroscopy. Attempts to prepare the ruthenium dihydride complexes, cis-[Ru(H)2(dppe)(PPh3)2] (dppe = Ph2PCH2CH2PPh2) and cw-[Ru(H)2(dppp)(PPh3)2] (dppp = Ph2PCH2CH2CH2PPh2) with larger bite-angled diphosphines dppe and dppp were unsuccessful.
Earlier work in our group on the effect of trans nitrile ligands in a series of complexes of the type (Formula)howed that the properties of the bound H2 are almost invariant with a change in the R group of the nitrile. hi an effort to compare those results with analogous ruthenium complexes bearing smaller bite-angled diphosphine, dppm, we synthesized and characterized a series of complexes of the type (Formula). We found that the properties of the bound H2 were once again invariant with a change in the R group of the nitrile.
In an effort to compare the effect of having two diphosphine ligands of different
bite angles with systems containing symmetrical diphosphine ligands reported by our
group,3 we synthesized a series of complexes of the type (Formula). These complexes exhibit hybrid properties in comparison to systems with symmetrical diphosphine ligands in terms of spectroscopic features and chemical reactivity.
Thus, the bite angle of the diphosphine ligand has a definite influence on the properties of the bound H2 ligand.
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Sivakumar, V. „Influence Of The Bite Angles Of Chelating Diphosphine Ligands In The Chemistry Of Ruthenium Hydride And Dihydrogen Complexes“. Thesis, Indian Institute of Science, 2006. http://hdl.handle.net/2005/293.
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The bite angle of a diphosphine ligand plays an important role in determining the reactivity of a transition metal complex. The coordinated dihydrogen on a transition metal center can be activated toward homolysis or heterolysis depending upon the nature of the metal center and the ancillary ligand environment. The present work deals with our investigations on the effect of the bite angle of the chelating diphosphine ligands in the chemistry of certain ruthenium hydride and dihydrogen complexes.
Protonation of the ds-[Ru(H)2(dppm)(PPh3)2] (dppm = Ph2PCH2PPh2) using HBF4-Et2O resulted in the dihydrogen/hydride complex trans-(Formula). This species shows dynamic exchange of the H-atom between the dihydrogen and the hydride ligands. The H-atom site exchange was studied by NMR spectroscopy. Attempts to prepare the ruthenium dihydride complexes, cis-[Ru(H)2(dppe)(PPh3)2] (dppe = Ph2PCH2CH2PPh2) and cw-[Ru(H)2(dppp)(PPh3)2] (dppp = Ph2PCH2CH2CH2PPh2) with larger bite-angled diphosphines dppe and dppp were unsuccessful.
Earlier work in our group on the effect of trans nitrile ligands in a series of complexes of the type (Formula)howed that the properties of the bound H2 are almost invariant with a change in the R group of the nitrile. hi an effort to compare those results with analogous ruthenium complexes bearing smaller bite-angled diphosphine, dppm, we synthesized and characterized a series of complexes of the type (Formula). We found that the properties of the bound H2 were once again invariant with a change in the R group of the nitrile.
In an effort to compare the effect of having two diphosphine ligands of different
bite angles with systems containing symmetrical diphosphine ligands reported by our
group,3 we synthesized a series of complexes of the type (Formula). These complexes exhibit hybrid properties in comparison to systems with symmetrical diphosphine ligands in terms of spectroscopic features and chemical reactivity.
Thus, the bite angle of the diphosphine ligand has a definite influence on the properties of the bound H2 ligand.
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Jacobsen, George M. „Synthesis, characterization, and reactivity of iron(II) and cobalt(II) complexes containing diphosphine ligands that feature a pendant amine base“. Connect to online resource, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3256473.
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Wu, Guanmin. „Synthesis, characterization, and kinetics of isomerization, C-H and P-C bond activation for unsaturated diphosphine-coordinated triosmium carbonyl clusters“. Thesis, University of North Texas, 2008. https://digital.library.unt.edu/ark:/67531/metadc6037/.
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Substitution of MeCN ligands in the activated cluster Os3(CO)10(MeCN)2 by the unsaturated diphosphine ligands (Z)-Ph2PCH=CHPPh2 (cDPPEn) or 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) proceeds rapidly at room temperature to furnish the ligand-bridged cluster 1,2-Os3(CO)10(P-P) (P-P represents cDPPEn or bpcd). Heating 1,2-Os3(CO)10(P-P) leads to the formation of the thermodynamically more stable chelating isomer 1,1-Os3(CO)10(P-P). Each compound of Os3(CO)10(P-P) has been characterized by x-ray diffraction, IR, 31P NMR and 1H NMR. Ligand isomerization kinetics have been investigated by UV-VIS and 31P NMR (for cDPPEn) or 1H NMR (for bpcd) spectroscopies. The isomerization mechanism is discussed based on the activation parameters and CO inhibition (for cDPPEn) or ligand trapping experiments (for bpcd). Thermolysis of 1,1-Os3(CO)10(bpcd) in refluxing toluene gives the hydrido cluster HOs3(CO)9[μ-(PPh2)C=C{PPh(C6H4)}C(O)CH2C(O)] and the benzyne cluster HOs3(CO)8(μ3-C6H4)[μ2,η1-PPhC=C(PPh2)C(O)CH2C(O)]. Photolysis of 1,1-Os3(CO)10(bpcd) using near UV light affords HOs3(CO)9[μ-(PPh2)C=C{PPh(C6H4)}C(O)CH2C(O)] as the sole product. HOs3(CO)8(μ3-C6H4)[μ2,η1-PPhC=C(PPh2)C(O)CH2C(O)] has been characterized in solution by IR and NMR spectroscopies. Furthermore its molecular structure has been determined by X-ray crystallography. Reversible C-H bond formation in HOs3(CO)9[μ-(PPh2)C=C{PPh(C6H4)}C(O)CH2C(O)] is demonstrated by ligand trapping studies to give 1,1-Os3(CO)9L(bpcd) (where L = CO, phosphine) via the unsaturated intermediate 1,1-Os3(CO)9(bpcd). The kinetics for reductive coupling in HOs3(CO)9[γ-(PPh2)C=C{PPh(C6H4)}C(O)CH2C(O)] and DOs3(CO)9[μ-(PPh2-d10)C=C{P(Ph-d5)(C6D4)}C(O)CH2C(O)] in the presence of PPh3 give rise to a kH/kD value of 0.88, whose magnitude supports the existence of a preequilibrium involving the hydride(deuteride) cluster and a transient arene-bound Os3 species that precedes the rate-limiting formation of 1,1-Os3(CO)9(bpcd). Strong proof for the proposed hydride(deuteride)/arene preequilibrium has been obtained from photochemical studies employing the isotopically labeled cluster 1,1-Os3(CO)10(bpcd-d4ortho), whose bpcd phenyl groups each contain one ortho hydrogen and deuterium atom. Equilibrium and kinetic isotope effects in the orthometallation step has been determined by 1H NMR in photochemical studies. Kinetics for the transformation from HOs3(CO)9[μ-(PPh2)C=C{PPh(C6H4)}C(O)CH2C(O)] to HOs3(CO)8(μ3-C6H4)[μ2,η1-PPhC=C(PPh2)C(O)CH2C(O)] has been studied by UV-VIS spectroscopy for which the mechanism is discussed.
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Wu, Guanmin Richmond Michael G. „Synthesis characterization, and kinetics of isomerization, C-H and P-C bond activation for unsaturated diphosphine-coordinated triosmium carbonyl clusters“. [Denton, Tex.] : University of North Texas, 2008. http://digital.library.unt.edu/permalink/meta-dc-6037.
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Samuels, Michiel C. „Solid phase strategies for the preparation of phosphorus ligand libraries“. Thesis, University of St Andrews, 2014. http://hdl.handle.net/10023/6357.
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Catalysis plays a key role in chemical conversions by making them faster and more selective. Despite its widespread use and decades of academic and industrial research, limited catalyst selectivity and stability still call for major improvements in catalyst performance to meet the demands of a sustainable society. Phosphine ligands are ubiquitous in transition metal chemistry and lead to extremely reactive and versatile homogeneous catalysts. Fast development of tailor-made catalysts and catalyst recovery are key issues in (asymmetric) homogeneous catalysis. Therefore libraries of ligands have to be synthesised and screened in an efficient way, which could be facilitated by Solid Phase Synthesis (SPS). Currently, most polymer bound ligands are anchored to the support after the synthesis in solution. However, the main advantages of synthesising the ligands directly on the polymeric support are not only easy catalyst recycling and product separation, but also the ease of purification during the synthesis steps, namely by simple washing and filtration. The use of SPS is very efficient for high throughput synthesis and screening of ligand libraries, however applications of SPS towards libraries of phosphorus ligands are rare, because the synthetic methodologies are still lacking. Here we present the development of methodologies towards novel immobilised bis(phosphine) ligands synthesised on polystyrene and JandaJel™ resin. By performing the synthesis steps on a solid support, the advantages of SPS are fully utilised. Successful routes have been developed towards immobilised secondary phosphine-boranes, which were versatile synthons to prepare a variety of new polymer-supported (C-chiral) bis(phosphine) ligands. These ligands were then tested for their catalytic activity in rhodium catalysed hydrogenation reactions.
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Fernandez, Cristina Carcedo. „Chiral diphosphine ligands derived from 1, 4:3, 6-dianhydro-d-mannitol : synthesis, co-ordination to transition metals and catalytic applications“. Thesis, Cardiff University, 2005. http://orca.cf.ac.uk/54551/.
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The synthesis of a new chiral diphosphine, l,4:3,6-dianhydro-2,5-bis(diphenylphosphino)-D-mannitol (ddppm) is reported, ddppm is derived from the commercially available C2-symmetric l,4:3,6-dianhydro-D-mannitol (Isomannide). This new ligand exhibits a bend butterfly-like geometry with the two-phosphine groups on the concave side. PPh, I PPh, H H ddppm The chelating ability of ddppm is demonstrated with the synthesis of several complexes with transition metals such as Cu, Pd, Pt, Rh, Ru and Ir. Some of these complexes have been successfully crystallized and tested in different catalytic reactions. These complexes haven been characterized and their properties are reported. Their ability to catalyse a range of reactions is also discussed in detail. Chapter 2 reports the synthesis of ddppm. This synthesis requires only two steps with the choice of the solvent being crucial for the formation of this ligand. ddppg, an epimer of ddppm, was also isolated as a by-product from the ddppm synthesis. This diphosphine is a non-chelating ligand unlike ddppm. Crystal structures of both isomers are shown in this chapter. PPh, I H H ddppg: 1,4:3,6-dianhydro-2,5-bis(dipheny lphosphino)-D-glucitol.
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Mayberry, Darrell D. „Synthesis, Characterization, and Reactivity of Prochiral Ruthenium Clusters and Bimetallic Rhenium Complexes with an Unsymmetrical Diphosphine and Hard-Soft Donor Ligands“. Thesis, University of North Texas, 2019. https://digital.library.unt.edu/ark:/67531/metadc1538707/.
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The reaction of [BrRe(CO)₄]₂ with 2-(diphenylphosphino)pyridine (PN) and 6-(diphenylphosphino)-2-formylpyridine (PON) was investigated. The reactions were regiospecific and exclusively produced the phosphorus-coordinated products, BrRe(CO)₄(κᵖ-PN) and BrRe(CO)₄(κᴾ-PON). The kinetics for the chelate ring closure (κᴾ→ κᴾᴺ) in BrRe(CO)₄(κᴾ-PN) were confirmed to occur by dissociative CO loss. The reaction of [BrRe(CO)₄]₂ with 2-(diphenylphosphino)pyridine (PN) was modeled computationally by DFT calculations. The preferred reaction pathway for the substitution reaction was determined to occur by direct attack of the pnictogen donor on the dimer and formation of the κᴺ isomer as the kinetic substitution product occurs. The κᴺ kinetic product then rapidly isomerizes to the κᴾ thermodynamic product by way of a reversible ligand dissociation. Treatment of the tetrahedral cluster H₂Ru₃(CO)₃(μ₃-S) (1) with 2-(diphenylphosphino)thioanisole (PS) furnishes the cluster H₂Ru₃(CO)₇(κ²-PS)(μ₃-S) (2). Cluster 2, which exhibits a chelated thiophosphine ligand (κ²-PS), exists as a pair of diastereomers with Keq = 1.55 at 298 K that differ in their disposition of ligands at the Ru(CO)(κ²-PS) center. The PS ligand occupies the equatorial sites (Peq, Seq) in the kinetic isomer and axial and equatorial sites (Pax, Seq) in the thermodynamically favored species. The reversible first-order kinetics to equilibrium have been measured experimentally by NMR spectroscopy and HPLC over the temperature range 293-323 K. The substitution reaction involving 1 and the isomerization of the PS ligand in 2 were investigated by DFT calculations. The computational results support a phosphine-induced expansion of the cluster polyhedron that is triggered by the associative addition of the PS donor to 1. The observed isomerization of the PS ligand in 2 is best explained by a tripodal rotation of the CO and PS groups at the Ru(CO)(κ²-PS) center that is preceded by a regiospecific migration of one of the edge-bridging hydrides to the non-hydride-bridged Ru-Ru bond in 2. The chiral clusters 1,2-Ru₃(μ-H)₂(μ₃-S)(CO)₇(μ-1p1,2p2-POP) (A) and 1,2-Ru₃(μ-H)₂(μ₃-S)(CO)₇(μ-1p2,2p1-POP) (B) were formed were formed from reaction of Ru₃(μ-H)₂(μ₃-S)(CO)₉ with 1-diphenylphosphino-2-[2-(diphenylphosphino)ethoxy]benzene (POP). Chiral clusters A and B were fully characterized by IR and NMR spectroscopy. Additionally, the molecular structure of A was solved by X-ray crystallography. Chiral cluster A was resolved into its enantiomers by preparative HPLC with a chiral column. The enantiomers were characterized by electronic circular dichroism (ECD) spectroscopy and their absolute stereochemical configuration was determined by X-ray crystallography.
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Poola, Bhaskar. „Synthesis and characterization of quinoxaline-functionalized, cage-annulated oxa- and thiacrown ethers and reaction chemistry of the diphosphine ligand 2,3-bis(diphenylphosphino)-N-p-tolylmaleimide (bmi) at triosmium carbonyl clusters“. Thesis, University of North Texas, 2006. https://digital.library.unt.edu/ark:/67531/metadc5608/.
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Quinoxaline-functionalized, cage-annulated oxa- and thiacrown ethers have been synthesized as possible specific metal host systems. The synthesis and characterization of quinoxaline-functionalized, cage-annulated oxa- and thiacrown ethers have been described. The characterization of these host systems have been fully achieved in solution by using various techniques such as IR, 1H NMR, and 13C NMR spectroscopic methods, high-resolution mass spectrometry (HRMS), elemental microanalysis, and X-ray crystallographic analysis in case of one quinoxaline-functionalized, cage-annulated oxacrown ether compound. The synthesis of the diphosphine ligand 2,3-bis(diphenylphosphino)-N-p-tolylmaleimide (bmi) is described. The substitution of the MeCN ligands in the activated cluster 1,2-Os3(CO)10(MeCN)2 by the diphosphine ligand bmi proceeds rapidly at room temperature to furnish a mixture of bridging and chelating Os3(CO)10(bmi) isomers and the ortho-metalated product HOs3(CO)9[μ-(PPh2)C=C{PPh(C6H4)}C(O)N(tolyl-p)C(O)]. Thermolysis of the bridging isomer 1,2-Os3(CO)10(bmi) under mild conditions gives the chelating isomer 1,1-Os3(CO)10(bmi), whose molecular structure has been determined by X-ray crystallography. The kinetics for the ligand isomerization have been investigated by UV-vis and 1H NMR spectroscopy in toluene solution over the temperature range of 318-348 K. On the basis of kinetic data conducted in the presence of added CO and the Eyring activation parameters, a non-dissociative phosphine migration across one of the Os-Os bonds is proposed. Orthometalation of one of the phenyl groups associated with the bmi ligand is triggered by near-UV photolysis of the chelating cluster 1,1- Os3(CO)10(bmi).
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Liu, Jie. „Substitution chemistry of the cobalt complexes RCCo3(CO)9 (R = H, CHO) with the diphosphine ligand: 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd). Syntheses, X-ray structures and reactivity“. Thesis, University of North Texas, 2001. https://digital.library.unt.edu/ark:/67531/metadc3043/.
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The reaction between the tetrahedrane cluster RCCo3(CO)9{R = CHO (1), H (3)} and the redox-active diphosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3- dione (bpcd) leads to the replacement of two CO groups and formation of RCCo3(CO)7(bpcd) {R = CHO (2), H (4)}. Clusters 2 and 4 are thermally unstable and readily transform into the new P-C bond cleavage cluster 5. All three clusters 2, 4, and 5 have been isolated and fully characterized in solution by IR and 31P NMR spectroscopy. VT 31P NMR data indicate that the bpcd ligand in RCCo3(CO)7(bpcd) is fluxional at 187 K in THF. Clusters 2, 4, and 5 have been structurally characterized by X-ray diffraction analyses.
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Stolze, Karoline. „Synthese und Charakterisierung niedervalenter Actinoidphosphidtelluride und ternärer Selen-Halogenid-Komplexe des Iridiums“. Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-202233.
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Metallpniktide und -chalkogenide erfahren zunehmend mehr Aufmerksamkeit in Chemie und Festkörperphysik. Dieses Interesse liegt unter anderem in der ungewöhnlichen Strukturchemie der Verbindungen begründet. In den Pniktogen(Pn)- bzw. Chalkogen(Q)-reichen Verbindungen dieser Systeme ist besonders häufig die Bildung der jeweiligen Oligo- oder Polyanionen bzw. Moleküle zu beobachten. Einerseits können die homoatomaren Pn–Pn- bzw. Q–Q-Bindungen zur Ausbildung niederdimensionaler Strukturmotive mit anisotropen Eigenschaften, wie bspw. Supraleitung und Metall-Halbleiter-Übergänge, führen; andererseits ergeben sich aus dem sterischen Raumanspruch der Struktureinheiten in Kombination mit den hohen Koordinationszahlen schwerer Übergangs- oder Actinoidmetalle komplexe Strukturen. Die Pn- bzw. Q-Atome treten häufig gemischtvalent auf, was zusammen mit den beschriebenen Strukturmerkmalen die enorme Variabilität und Anpassungsfähigkeit dieser Stoffsysteme widerspiegelt.
Im Rahmen des ersten Teils der vorliegenden Dissertation wurde die potentielle Oligoanionenbildung in den bisher als quadratisch-planar beschriebenen Phosphidschichten von Actinoidphosphidtelluriden diskutiert. Über eine chemische Transportreaktion mit Iod ist es gelungen Kristalle des Uranphosphidtellurids UPTe und des verwandten, bisher unbekannten Diuranphosphidditelluridoxids U2PTe2O zu züchten und die Kristallstrukturen durch Einkristallröntgendiffraktometrie aufzuklären. Die Strukturen beider Verbindungen können durch eine Abfolge von [U2P2]- und [Te2]-Schichten, bzw. [U2P2]-, [U2O2]- und [Te2]-Schichten entlang [001] beschrieben werden. Die Phosphoratome in den [U2P2]-Abschnitten bilden eine Schicht parallel ausgerichteter P2-Anionen. Die Zusammenlagerung der Phosphoratome sowie die geordnete Ausrichtung der Hanteln bedingt eine Symmetriereduktion der ursprünglich tetragonal angenommenen Struktur mit fehlgeordneten Phosphoratomen hin zu einem Strukturmodell in der monoklinen Raumgruppe I11m. Bindungsanalysen im Realraum mit Hilfe des Elektronen-Lokalisierbarkeits-Indikator (ELI D) ergaben für UPTe in der monoklin verzerrten Struktur ein zusätzliches Doppelmaximum auf der gedachten Linie zwischen den Phosphoratomen P1 und P2, welches als homoatomare P–P-Bindungen interpretiert werden kann.
Zudem konnte über eine Festkörpersynthese die ternäre Verbindung Thoriumphosphidtellurid ThPTe erhalten werden, deren Pulverröntgendaten ein zu UPTe analoges Strukturbild zeigt. Wenngleich die Fehlordnung in der Phosphorschicht von ThPTe experimentell nicht aufgelöst werden konnte, war es durch Raman-Spektroskopie möglich, die Existenz der P2 Hanteln sowohl in ThPTe als auch in UPTe zu belegen. Beide isotype Verbindungen können in ionischer Grenzschreibweise als A4+ + ½ P24– + Te2– (A = Th, U) formuliert werden.
Im zweiten Teil der vorliegenden Dissertation wurde die vielfältige Strukturchemie neuer Selen-Halogenid-Komplexe des Iridiums insbesondere hinsichtlich ihrer Oligoselenidliganden sowie koordinativ gebundener Selenmoleküle dargelegt. Durch die Aktivierung von elementarem Iridium in Selentetrahalogenid-Schmelzen konnten erstmalig Verbindungen im System Ir–Se–Br dargestellt und die Strukturvielfalt im System Ir–Se–Cl signifikant erweitert werden. Die synthetisierten ein- bis achtkernigen Iridium(III)-Komplexe zeichnen sich durch eine bemerkenswerte Diversität ihrer Liganden aus, die von Halogenidionen, Selenmono- und Selendihalogenid-Einheiten über zyklische Selenmoleküle bis zu Oligoselenidketten reicht. Die variablen Verknüpfungsmoden dieser Liganden erweitern zusätzlich das Spektrum möglicher Komplexformen und -größen.
Die kleinsten, dargestellten ternären Iridiumkomplexe a-fac-[IrBr3(SeBr2)3], m-fac-[IrBr3(SeBr2)3] und mer-[IrBr3(SeBr2)3] besitzen ausschließlich endständige Selendibromid- und Bromidliganden, die sich in ihrer Konfiguration unterscheiden.
In den isotypen, zweikernigen Iridiumkomplexen [Se9(IrX3)2] (X = Cl, Br, Cl/Br) wird ein ungeladener, unter den Allotropen des Selens unbekannter Se9-Ring in Kronen-Konformation durch zwei IrX3-Moleküle stabilisiert. Der cyclo-Nonaselenligand ist der erste seiner Art, der mittels Röntgenbeugung am Einkristall charakterisiert werden konnte. Se9(IrCl1.66(1)Br1.34(1))2 repräsentiert zudem die erste quaternäre Verbindung in den Systemen M–Se–Cl–Br (M = Platinmetalle).
Die ringförmigen, vier- und sechskernigen Komplexe [Ir4Se10Br16] sowie [Ir6Se8Cl30] und [Ir6Se6Cl30] zählen zu den größten Ringstrukturen unter den Chalkogen-Halogeniden der Platinmetalle. Ihre intramolekulare Verknüpfung wird unter anderem durch µ-verbrückende X–-Anionen und sehr seltene (SeX)–-Einheiten realisiert. Die verwandten [Ir6Se8Cl30]- und [Ir6Se6Cl30]-Ringe können als molekularer Ausschnitt der aus [IrCl6/2]-Oktaedern bestehenden Honigwabenstruktur von alpha-IrCl3 beschrieben werden.
Die achtkernigen Iridiumkomplexe [Ir8Se28Br14] und [Ir8Se40Br10] bilden über die sechsfach-verbrückenden Se22–-Hanteln und die vierfach-verbrückenden Se42–-Ketten sehr große, ellipsoide Moleküle aus, die stark einem Ausschnitt aus der Netzwerkstruktur von Ir3Se8 ähneln. Beide Komplexe unterscheiden sich lediglich in ihren apikal koordinierenden Liganden: SeBr2-Einheiten im Fall von [Ir8Se28Br14] und ungeladene Heptaselenringe im Fall von [Ir8Se40Br10]. Die Se7-Moleküle repräsentieren ihrerseits die ersten cyclo-Heptaseleneinheiten in Boot-Konformation. An den [Ir8Se28Br14] Komplex koordinieren über Wasserstoffbrückenbindungen zusätzlich zwei Wassermoleküle. Die räumliche Anordnung der Moleküle im Festkörper von Ir8Se28Br14·2H2O stellt eine hervorragende Näherung der dichtesten Ellipsoidpackung dar.
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Alberico, Elisabetta [Verfasser]. „Optically active [(η6-arene)Cr(CO)3]-based [(eta6-arene)Cr(CO)3-based] diphosphines : synthesis and application in asymmetric homogeneous hydrogenation / vorgelegt von Elisabetta Alberico“. 2003. http://d-nb.info/970879490/34.
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Bhowmick, Arnab. „Synthesis and characterization of transition metal cluster containing diphosphine ligands“. Thesis, 2012. http://ethesis.nitrkl.ac.in/3085/2/Online_project_on_metal_clusters.pdf.
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Various metal complexes containing transitional metal elements have been prepared. Using shlenk line technique . Spectroscopic analysis by IR and NMR shows that two types of diphosphine co-ordinated metal clusters have been obtained,one having chelating mode of binding [Fe3SeTeCO)7{(PPh2)(C5H4)Fe(C5H4)(PPh2)}] ,and the another is having mono dentate co-ordination [Fe3Te2(CO)8{(PPh2) (C5H4)Fe(C5H4)(PPh2)}].
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Wu, Zih-Shing, und 吳梓翔. „Synthesis and Characterization of Rhenium Isocyanide Complexes and Ruthenium Diphosphine Complexes“. Thesis, 2008. http://ndltd.ncl.edu.tw/handle/17291636285220419350.
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碩士高雄醫學大學
醫藥暨應用化學研究所碩士班
96
The preparation and characterization of RuCl2(POMe)2 (POMe = diphenyl(2-methoxyphenyl)phosphine) was reported. However, the reactions of RuCl2(POMe)2 with refluxing RCN (R = Me, Et) led to loss of CH3Cl to give Ru(RCN)2(PO)2 (R = Me(1), Et(3)), which are never reported. Adding KPF6 or KBF4 in the reactions will give additional products [Ru(RCN)2(PO)(POMe)]+ (R = Me(2), Et(4)) according to the solvent selection. Complexes 2 and 4 were observed the dealkylating via loss of CH3Cl or [CH3(POMe)]+ pathways. The [CH3(POMe)]+ pathway needs excess POMe which may come from the thermal decomposition of [RuCl(POMe)2(RCN)]+. The NMR and ESI-mass monitoring spectra also help us to understand the Ru complexes dealkylation pathway. The structures of 1, 2, and 3 were confirmed by X-ray analyses.
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MacFarlane, Kenneth Shawn. „Synthesis, characterization, and reactivity of ruthenium(II)-diphosphine complexes for catalytic homogeneous hydrogenation“. Thesis, 1995. http://hdl.handle.net/2429/4792.
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Li, Guo An, und 李國安. „supercritical fluid synthesis of copper diphosphide nanowires for energy storage applications“. Thesis, 2016. http://ndltd.ncl.edu.tw/handle/386cqq.
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博士國立清華大學
化學工程學系
105
Phosphorus-rich transition metal phosphide CuP2 nanowires were synthesized with high quality and high yield (∼60%) via the supercritical fluid−liquid−solid (SFLS) growth at 410 °C and 10.2 MPa. The obtained CuP2 nanowires have a high aspect ratio and exhibit a single crystal structure of monoclinic CuP2 without any impurity phase. CuP2 nanowires have progressive improvement for semiconductors and energy storages compared with bulk CuP2. Being utilized for back-gate field effect transistor (FET) measurement, CuP2 nanowires possess a p-type behavior intrinsically with an on/off ratio larger than 104 and its single nanowire electrical transport property exhibits a hole mobility of 147 cm2 V−1 s−1, representing the example of a CuP2 transistor. In addition, CuP2 nanowires can serve as an appealing anode material for a lithium-ion battery electrode. The discharge capacity remained at 945 mA h g−1 after 100 cycles, showing a good capacity retention of 88% based on the first discharge capacity. Even at a high rate of 6 C, the electrode still exhibited an outstanding result with a capacity of ∼600 mA h g−1. Ex-situ transmission electron microscopy and CV tests demonstrate that the stability of capacity retention and remarkable rate capability of the CuP2 nanowires electrode are attributed to the role of the metal phosphide conversion-type lithium storage mechanism. Finally, CuP2 nanowire anodes and LiFePO4 cathodes were assembled into pouch-type lithium batteries offering a capacity over 60 mA h. The full cell shows high capacity and stable capacity retention and can be used as an energy supply to operate electronic devices such as mobile phones and mini 4WD cars. However, due to increasing demand for lithium-ion batteries, lithium metal on earth cannot meet the need so that the price of lithium increases year by year. Future work must be looking for high abundance of alternative materials as ion conduction of battery. Sodium ion battery is currently one of the most feasible option. We applied previously calcined copper phosphide nanowires to sodium ion batteries, and electrochemical results shows that capacity possesses 975 mA h g-1 after 100 charge/discharge cycle, with retention 95%.
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Rodríguez-Bárzano, A., Rianne M. Lord, A. M. Basri, Roger M. Phillips, A. J. Blacker und P. C. McGowan. „Synthesis and anticancer activity evaluation of η5-C5(CH3)4R ruthenium complexes bearing chelating diphosphine ligands“. 2014. http://hdl.handle.net/10454/9498.
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yesThe complexes [RuCp*(PP)Cl] (Cp* = C5Me5; [1], PP = dppm; [4], PP = Xantphos), [RuCp#(PP)Cl] (Cp# = C5Me4(CH2)5OH; [2], PP = dppm; [5], PP = Xantphos) and [RuCp*(dppm)(CH3CN)][SbF6] [3] were synthesized and evaluated in vitro as anticancer agents. Compounds 1–3 gave nanomolar IC50 values against normoxic A2780 and HT-29 cell lines, and were also tested against hypoxic HT-29 cells, maintaining their high activity. Complex 3 yielded an IC50 value of 0.55 ± 0.03 μM under a 0.1% O2 concentration.
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Lin, Chien-Nan, und 林建男. „Dicyanobenzene-, Diphosphine-, and N-Heterocyclic Carbene-Bridged EFe3Cu2 (E = S, Se, Te) Complexes: Synthesis, Transformation, Semiconductivity, and Catalysis“. Thesis, 2015. http://ndltd.ncl.edu.tw/handle/74844266434313295108.
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博士國立臺灣師範大學
化學系
103
1. S/Fe/Cu/Dppx System A reversible vapochemical and mechanochemical solid-state transformation between a dppe-linked SFe3Cu2-based cluster [{(m3-S)Fe3(CO)9}Cu2(dppe)] and its 1D polymer [{(m4-S)Fe3(CO)9}Cu2(dppe)(MeCN)2]n, was demonstrated, in which polymer [{(m4-S)Fe3(CO)9}Cu2(dppe)(MeCN)2]n exhibited semi-conducting properties with an energy gap of 1.69 eV. 2. Se, Te/Fe/Cu/p-DCB System When solid reactants [EFe3(CO)9Cu2(MeCN)2] (E = Se, Te) and 1,4-dicyanobenzene (p-DCB) were mixed in 1:1 and 1:1.5 ratios and ground with drops of THF, two EFe3(CO)9Cu2-based THF-encapsulated single/double and single/single p-DCB-linked 1D polymers [SeFe3(CO)9Cu2(p-DCB)1.5•0.5THF]n (1a-THF) and [TeFe3(CO)9Cu2(p-DCB)•THF]n (2b-THF) were obtained, respectively. X-ray analysis showed that the neighboring benzenes of the double p-DCB linkers of 1a-THF displayed a parallel-displaced geometry with an intramolecular pi···pi interaction and the oxygen atom of the lattice THF of 1a-THF or 2b-THF interacted with its adjacent hydrogen atoms of the p-DCB ligands to give weak C─H…O hydrogen bonds. When the grinding solvent changed into CH2Cl2, only TeFe3(CO)9Cu2-based single/double p-DCB-linked polymer [TeFe3(CO)9Cu2(p-DCB)1.5]n (1b) was obtained. Instead, upon heating at 60 oC under vacuum, the lattice THF of 1a-THF could be removed to give [SeFe3(CO)9Cu2(p-DCB)1.5]n (1a). 1a and 1b were isomorphous and exhibited tight crystal-packed structures. Interestingly, when [EFe3(CO)9Cu2(MeCN)2] and p-DCB were mixed in a 1:1.5 ratio and ground with CH2Cl2/toluene (v/v = 1/1), the EFe3(CO)9Cu2-based toluene-encapsulated single/double p-DCB-linked polymers [EFe3(CO)9Cu2(p-DCB)1.5•0.5toluene]n (E = Se, 1a-toluene; Te, 1b-toluene) were obtained, in which the benzene ring of the guest toluene and its adjacent hydrogen atom of the titled benzene of the p-DCB ligand showed significant C─H···pi interaction. In addition, mechanochemically reversible solid-state structural transformations among 1a, 1a-THF, and 1a-toluene, as well as 1b-toluene, 2b-THF, and 1b were achieved by grinding with THF, CH2Cl2, CH2Cl2/toluene, or additional p-DCB ligands, accompanied with the uptake and removal of the lattice solvent, the slippage of the packing layers, and crystal to crystal expansion and contraction. In addition, the measurement of conductivity showed that polymers 1a(1b), 1a(1b)-toluene, and 2b-THF exhibited semiconducting behaviors (dc conductivity, 10−3−10−2 Ω−1cm−1; energy gap, 1.42−1.50 eV) which could be tuned by weak pi···pi interaction and C─H···O hydrogen bonding, elucidated by DFT calculations. 3. Te/Fe/Cu/NHC System A new type of TeFe3(CO)9-incorporated dicopper N-heterocyclic carbene (NHC) complexes was obtained directly from one-pot reactions. By the introduction of the electron-donating and bulky cluster anion [TeFe3(CO)9]2− and NHCs as the ligands, these di-Cu(I)-based complexes exhibited pronounced catalyst activities toward the homocoupling of arylboronic acids with low Cu loadings (0.5 or 1.0 mol%) and high yields (up to 98%).
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Elowe, Paul Richard. „The Selective Oligomerization of Ethylene Using Chromium Diphosphine Catalysts and the Synthesis and Reactivity of Group 7 Carbonyl Derivatives Relevant to Synthesis Gas Conversion“. Thesis, 2009. https://thesis.library.caltech.edu/5240/1/1_Title.pdf.
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The work presented in this thesis explores two distinct fields of organometallic chemistry with a common goal of selectively transforming cheap and abundant feedstocks to value-added chemicals using homogeneous catalysts.
Chapter 1 presents the synthesis and characterization of a series of bis(diphenylphosphino)amine ligands and their corresponding chromium(III) trichloride complexes. The isolated chromium complexes are precursors to highly active catalysts for the selective oligomerization of ethylene to 1-hexene and 1-octene. The unique feature of the ligands presented herein is the presence of coordinating functionalities tethered to the nitrogen backbone. These act as hemilabile donors, which stabilize the active species and/or transition states during catalysis. This increased stability leads to more productive catalysts. Furthermore, important solvent and additive effects have been investigated. While reactions in non-polar solvents exhibit poor activity at lower ethylene pressures, those in more polar solvents are highly active and generate very little undesired polymer. Varying the solvent has a significant impact on 1-hexene/1-octene selectivity as well. Experiments with potentially coordinating additives result in a higher tendency for 1-octene formation. An investigation of catalyst decomposition is also discussed.
Chapter 2 presents synthetic, structural and reactivity studies on a series of Group 7 carbonyl derivatives relevant to synthesis gas conversion. Reduction of the carbonyl precursors with a hydride source generates the corresponding formyl species. This reaction is facilitated when more electrophilic carbonyl complexes are employed. Neutral and cationic Fischer carbene complexes were prepared by the reaction of the formyl species with boranes and alkyltriflates, respectively. Further reduction of Group 7 methoxycarbenes with a hydride leads to the formation of a reactive methoxymethyl species. Dimethyl ether release is obtained from treatment of a manganese methoxymethyl species with a hydride. Moreover, subjecting manganese methoxymethyl complexes to an atmosphere of CO generates acyl complexes via migratory insertion. Preliminary mechanistic details are presented.
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Wang, Chih-Chin, und 王致欽. „Diphosphine-, Dipyridyl-, and N-Heterocyclic Carbene-Bridged EFe3Cu2 (E = S, Se, Te) Complexes: Synthesis, Reactivity, Optical properties, and Catalysis“. Thesis, 2016. http://ndltd.ncl.edu.tw/handle/93291126112830988787.
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Tai-YenLin und 林泰言. „Syntheses and Characterization of Lead(II), Copper(I) and Iron(II) Complexes with tetradentate diphosphine-dithiolate ligand derivatives“. Thesis, 2015. http://ndltd.ncl.edu.tw/handle/17925395142905230744.
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碩士國立成功大學
化學系
103
Our laboratory has developed a series of phosphine-thiolate ligands in order to understand metal thiolate chemistry. It is anticipated the information provided from this study can bring insights for understanding the metal-sulfur chemistry in biological systems as well as in toxicity. In this thesis, diphosphine-dithiolate ligand (P2S2) was utilized for exploring metal chemistry. 31P, 207Pb NMR in solid and solution state were applied on two lead(II) compelexes, Pb(P2S2”) (1) and [Pb(P2S2”)]2·[Pb2(P2S2”)2] (2). Pb(P2S2”) (1) is a monolead(II) species binding with a P2S2” ligand. [Pb(P2S2”)]2·[Pb2(P2S2”)2] contains two monolead(II) units and a dimeric unit. These compounds were synthesized and characterized in our laboratory before. In addition, a hexacopper(I) complex of P2S2” ligand, [Cu3(P2S2”)(Im)(TMSPhS)]2 , has been isolated and characterized by X-ray crystallography and spectroscopies. Finally, iron carbonyl chemistry with P2S2” ligand was also been explored. The isolated compound was identified as cis-Fe(P2S2”)(CO)2 by comparing the spectroscopies with the other analogue cis-Fe(P2S2*)(CO)2, that is synthesized and well characterized in our laboratory.