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Phosphane
Terms modified by Phosphane Selected AbstractsTetranuclear (Phosphane)(thiolato)gold(I) Complexes: Synthesis, Characterization and Photoluminescent Properties,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 25 2007Eduardo J. Fernández Abstract The reactions of the tetraphosphane donor ligand (Ph2PCH2)2NCH2CH2N(CH2PPh2)2 with the gold precursors [AuCl(tht)] or [Au(C6F5)(tht)] (tht = tetrahydrothiophene) leads to complexes [Au4R4{(Ph2PCH2)2NCH2CH2N(CH2PPh2)2}] [R = Cl (1) or C6F5 (2)]. Further substitution of the chlorine atoms in 1 by the corresponding 4-substituted benzenethiolates gives rise to the tetranuclear (phosphane)(thiolato)gold(I) complexes [Au4(S-C6H4 -X)4{(Ph2PCH2)2NCH2CH2N(CH2PPh2)2}] [X = F (3), MeO (4), Me (5) and NO2 (6)]. Complexes 2 and 4 were characterized by X-ray diffraction studies showing Au···Au interactions in the case of complex 4. Complexes 3,6 display intense emissions in the solid state at 77 K with lifetimes in the microsecond range. The observed phosphorescent emissions are attributed to metal-to-ligand charge-transfer transitions. Nevertheless, the influence in the emission energies of gold,gold interactions or the contribution of the substituent in the 4-position of the benzenethiolate ring to the excited state cannot be neglected. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Chelating Phosphane,Boranes as Hemilabile Ligands , Synthesis of[Mn(CO)3(,2 -H3B·dppm)][BArF4] and [Mn(CO)4(,1 -H3B·dppm)][BArF4]EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 20 2006Nicolas Merle Abstract Manganese complexes bearing the chelating phosphane,borane ligand H3B·dppm [dppm = bis(diphenylphosphanyl)methane] have been prepared. Addition of H3B·dppm to Mn(CO)5Br using Na[BArF4] as a halide-abstracting reagent affords [Mn(CO)3(,2 -H3B·dppm)][BArF4] (1). This reacts with CO to open the bidentate borane to afford [Mn(CO)4(,1 -H3B·dppm)][BArF4] (2) in which the borane is now bound in a monodentate manner. The CO addition is reversible, and placing 2 under vacuum (hours) regenerates 1 quantitatively, demonstrating that the chelating phosphane,boranes can act as hemilabile ligands. The complexes 1 and 2 have been fully characterised by NMR spectroscopy and X-ray crystallography. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Gold(I) Complexes of P,N Ligands and Their Catalytic ActivityEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 7 2010Chosu Khin Abstract Gold(I) complexes were readily prepared by reaction of the respective ligands with (Me2S)AuCl in CH2Cl2. Complexes of formula LAuCl {L = diphenyl(2-pyridyl)phosphane (PPh2Py), (R)-(+)-4-[(2)-(diphenylphosphanyl)-1-naphthyl]- N -[(R)-1-phenylethyl]-1-phthalazinamine (PINAP)} were obtained when a 1:1 molar ratio of ligand to starting gold precursor was used. When a 2:1 ratio of ligand to gold precursor was used with PPh2Py or MandyPhos as ligands, complexes of the type L2AuCl were obtained. All complexes were fully characterized, and single-crystal X-ray structures could be determined for four complexes. Chloride ions were removed by reaction with silver salts, such as AgNTf2, AgOTf and AgBF4, for the use of these complexes as catalysts. After the catalytic reaction with alkynes and alcohols in acetonitrile, a unique trinuclear gold(I) complex derived from [(PPh2Py)Au]BF4 could be characterized by X-ray structural analysis, showing a mode of catalyst deactivation. [source] Hydrido-Osmium(II), -Osmium(IV) and-Osmium(VI) Complexes with Functionalized Phosphanes as Ligands,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 35 2009Birgit Richter Abstract Reaction of five-coordinate [OsHCl(CO)(PiPr3)2] (1) with the chelating phosphane iPr2PCH2CO2Me gave six-coordinate [OsHCl(CO)(PiPr3){,2(P,O)- iPr2PCH2C(=O)OMe}] (2), which upon treatment with CO and O2 afforded the 1:1 adducts [OsHCl(CO)(L)(PiPr3){,(P)- iPr2PCH2CO2Me}] (3, 4) by partial opening of the chelate ring. The vinyl complex [OsCl(CH=CHPh)(CO)(PiPr3){,2(P,O)- iPr2PCH2C(=O)OMe}] (5) was obtained from 2 and PhC,CH by insertion of the alkyne into the Os,H bond. Reaction of 2 with sodium acetate led to metathesis of the anionic ligands and formation of [OsH(,2 -O2CCH3)(CO)(PiPr3){,(P)- iPr2PCH2CO2Me}] (6). Osmium(VI) compounds [OsH6(PiPr2R)2] with R = CH2CH2OMe (12), CH2CO2Me (13) and CH2CO2Et (14), and [OsH6(PiPr3){,(P)- iPr2PCH2CH2NMe2}] (16) were prepared from osmium(IV) precursors and shown to rapidly react with O2 and primary alcohols. Exploratory studies revealed that the catalytic activity of the hexahydrido complexes in the hydrogen transfer reaction from 2-propanol to cyclohexanone and acetophenone depends on the type of the functionalized phosphane and is best for R = CH2CH2OMe. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] The Variable Binding Modes of Phenylbis(pyrid-2-ylmethyl)phosphane and Bis(pyrid-2-ylmethyl) Phenylphosphonite with AgI and CuIEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 20 2009Fernando Hung-Low Abstract A series of new bridging phosphane and phosphonite structures forming three- and six-membered rings with the metal centers were synthesized and characterized. The resulting compounds of phenylbis(pyrid-2-ylmethyl)phosphane (1) with the silver(I) salts of trifluoroacetate (tfa,), tetrafluoroborate (BF4,), and trifluoromethanesulfonate (OTf,), and copper tetrakis(acetonitrile) hexafluorophosphate (PF6,) shows the flexibility of the ligand by displaying different coordination modes associated with the electronic and structural characteristics of the corresponding anion. Accordingly, ligand 1 in these complexes displays two different binding modes. With Agtfa and AgBF4 compounds 3 and 4 are obtained where the ligand chelates to two silver atoms that exhibit normalAg,Ag contacts in the range of 2.9 Å. When AgOTf or Cu(NCCH3)4PF6 are used, one molecule of 1 bridges the metal centers through a phosphorus atom while another is terminally bound. This induces short M,M distances of 2.6871 and 2.568 Å for 5 and 6, respectively. Similarly, the coordination behavior of the heterofunctional bis(pyrid-2-ylmethyl) phenylphosphonite ligand (2) is reported with Cu(NCCH3)4PF6 (7) and AgBF4 (8) to form two novel discrete molecules. In these complexes 2 coordinates through the P and N atoms, with the difference that in 7 the O atom of one of the carbinol arms is also bound to the Cu. Elemental analysis, variable-temperature multinuclear NMR spectroscopy, single-crystal X-ray diffraction, and low-temperature luminescence studies were carried out to fully characterize the compounds. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] A Simple Building-Block Route to (Phosphanyl-carbene)palladium Complexes via Intermolecular Addition of Functionalised Phosphanes to IsocyanidesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 10 2009Michael R. Eberhard Abstract We present a straightforward protocol for making (phosphanyl-carbene)PdII complexes. These complexes have bidentate ligands containing an acyclic diamino- or aminooxy-carbene and a phosphane. The synthesis gives good yields (typically 70,90,%) for a variety of complexes (22 compounds). Moreover, it does not require the synthesis of imidazolium salts nor the a priori generation of free carbenes. Three of the new complexes were tested as catalysts for Sonogashira and Hay coupling reactions, with good yields and selectivities. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Preparation, Geometric and Electronic Structures of [Bi2Cu4(SPh)8(PPh3)4] with a Bi2 Dumbbell, [Bi4Ag3(SePh)6Cl3(PPh3)3]2 and [Bi4Ag3(SePh)6X3(PPhiPr2)3]2 (X = Cl, Br) with a Bi4 UnitEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 32 2008Heino Sommer Abstract BiBr3 and CuCl react with S(Ph)SiMe3 in thf solution in the presence of PPh3 to yield [BiCu2(SPh)3Br2(PPh3)3] (1). The reaction of 1 with 2 equiv. of NaSPh gives rise to [Bi2Cu4(SPh)8(PPh3)4] (2) containing a Bi2 dumbbell. In this paper we further report the synthesis and characterization of the new cluster complexes [Bi4Ag3(SePh)6Cl3(PPh3)3]2 (3) and[Bi4Ag3(SePh)6X3(PPhiPr2)3]2 [X = Cl (4), Br (5)]. In the surprisingly formed species 3,5 a formal charged Bi46+ unit is observed. Compounds 3,5 were prepared by the reaction of BiX3 (X = Cl, Br), AgStBu, Se(Ph)SiMe3 and phosphane (PPh3, PPhiPr2). The structures of the compounds were determined by single-crystal X-ray analysis. Additionally, theoretical investigations were preformed to rationalize the bonding situation in 2,5. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] An Atropo-Stereogenic Diphosphane Ligand with a Proximal Cationic Charge: Specific Catalytic Properties of a Palladium Complex ThereofEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2008Nathalie Debono Abstract A class of cationic diphosphane ligands combining phosphane and amidiniophosphane moieties is illustrated on the N -methyl,N -naphthylbenzimidazolium framework. The palladium(II) complex thereof is described and compared to the corresponding complex of the analogous neutral diphosphane. Contrary to first-level expectations, the N2C,P and N2CP,Pd bonds in the cationic diphosphane complex are not longer than those occurring in its neutral counterpart. In the cationic ligand, the proximal positive charge is indeed conjugated to one phosphanyl group, and the coordination scheme is tentatively interpreted by resonance of the phosphane,metal dative bond (+N2C,P:,[Pd]) with a carbene,phosphenium dative bond (N2C:,[+P:,Pd]). Despite this peculiar structural feature, the electronic , donation (vs. , acceptation) towards the palladium centre remains lowered in the cationic ligand. This specific property can be a priori valuable in a catalytic process where oxidative addition is not the limiting step. It is indeed shown that although the neutral complex is more active in Suzuki coupling reactions, the cationic complex is more active in Sonogashira-type coupling reactions involving predissociated halide substrates, namely an acyl chloride. These likely atropo-chiral ligands deserve to be resolved for application in asymmetric catalysis.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Study of the Effect of the Phosphane Bridging Chain Nature on the Structural and Photophysical Properties of a Series of Gold(I) Ethynylpyridine ComplexesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 18 2008Montserrat Ferrer Abstract Alkynyl AuI complexes of the type [Au(C,CC5H4N)(PPh3)] (1) [Au2(C,CC5H4N)2 (diphosphane)] [diphosphane = bis(diphenylphosphanyl)methane (2), bis(diphenylphosphanyl)isopropane] (3), bis(diphenylphosphanyl)acetylene (4), 1,2-bis(diphenylphosphanyl)ethane (5), 1,3-bis(diphenylphosphanyl)propane (6), 1,4-bis(diphenylphosphanyl)butane (7), 1,1,-bis(diphenylphosphanyl)ferrocene (8) and [Au3(C,CC5H4N)3(triphos)] [triphos = 1,1,1-tris(diphenylphosphanylmethyl)ethane] (9) were prepared by reaction of [Au(C,CC5H4N)]n with the suitable phosphane. Determination of the X-ray crystal structures of several compounds bearing different carbon backbones between the phosphorus atoms reveals the influence of the nature of the phosphane spacer on the establishment of intra and/or intermolecular gold,gold interactions. The absorption and emission properties of the complexes were analysed by taking into account the presence or absence of intermetallic interactions. Although UV/Vis spectra show differences for compounds with intramolecular Au,Au contacts, a conclusive trend was not observed in the emission behaviour. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Tetranuclear (Phosphane)(thiolato)gold(I) Complexes: Synthesis, Characterization and Photoluminescent Properties,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 25 2007Eduardo J. Fernández Abstract The reactions of the tetraphosphane donor ligand (Ph2PCH2)2NCH2CH2N(CH2PPh2)2 with the gold precursors [AuCl(tht)] or [Au(C6F5)(tht)] (tht = tetrahydrothiophene) leads to complexes [Au4R4{(Ph2PCH2)2NCH2CH2N(CH2PPh2)2}] [R = Cl (1) or C6F5 (2)]. Further substitution of the chlorine atoms in 1 by the corresponding 4-substituted benzenethiolates gives rise to the tetranuclear (phosphane)(thiolato)gold(I) complexes [Au4(S-C6H4 -X)4{(Ph2PCH2)2NCH2CH2N(CH2PPh2)2}] [X = F (3), MeO (4), Me (5) and NO2 (6)]. Complexes 2 and 4 were characterized by X-ray diffraction studies showing Au···Au interactions in the case of complex 4. Complexes 3,6 display intense emissions in the solid state at 77 K with lifetimes in the microsecond range. The observed phosphorescent emissions are attributed to metal-to-ligand charge-transfer transitions. Nevertheless, the influence in the emission energies of gold,gold interactions or the contribution of the substituent in the 4-position of the benzenethiolate ring to the excited state cannot be neglected. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Preferred Phosphorus Ylide Formation Upon Alkylation of Lithiobis(diphenylphosphanyl)acetonitrile,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2007Leonie Braun Abstract Deprotonation of the readily available chelate phosphane bis(diphenylphosphanyl)acetonitrile (6) leads to stabilized carbanion system 7. Lithiobis(diphenylphosphanyl)acetonitrile (7) features a unique thf-stabilized monomeric structure in the crystal form with a short cyanonitrogen,Li contact. Alkylation of 7 with n -alkyl bromides (R,Br, R = ethyl, n -propyl, n -butyl, n -hexyl) takes place selectively at one phosphorus atom to yield stabilized ylides 8a,d (two examples characterized by X-ray diffraction). Treatment of 7 with the more reactive alkylation agents methyl iodide or benzyl bromide results in alkylation at both phosphorus atoms to give delocalized bis(phosphonium)ylides 9a,b (both characterized by X-ray diffraction). Similarly, the reaction of 7 with 1,3-dibromopropane or 1,4-dibromobutane yields six- and seven-membered heterocyclic bis(phosphonium)ylides 10a,b, respectively. The spectroscopic characterization and X-ray crystal structure analysis again indicate the presence of delocalized Ph2RP,C(CN),PRPh2 substructures. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Tris(dibenzo[a,d]cycloheptenyl)phosphane: A Bulky Monodentate or Tetrapodal LigandEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 18 2007Urs Fischbach Abstract The tetradendate phosphane tris(5H -dibenzo[a,d]cyclohepten-5-yl)phosphane (trop3P, 1) was synthesized from tris(trimethylsilyl)phosphane and 5-chloro-5H -dibenzo[a,d]cycloheptene. Sulfurization of 1 with elemental sulfur led to trop3P=S. Complexes of 1 with AgI, AuI, RhI, IrI, and PdII were prepared. The structures of trop3P (1), trop3P=S (2), [AgCl(trop3P)] (3), [Au(trop3P)(MeCN)]PF6 (5), [RhCl(trop3P)] (6) and [Pd(trop3P)(H2O)](OTf)2 (9) were determined by X-ray diffraction studies. In the coinage metal complexes, 1 serves as monodentate extremely bulky ,1 -phosphane ligand (cone angle ca. 250°). In the RhI, IrI, and PdII complexes, 1 acts as tetradendate ligand. CP MAS NMR spectroscopy shows that the span of the chemical shift tensor increases in 7, 6, and 9 in this order (, = 310 ppm, 410 ppm, 465 ppm) and contains two strongly deshielded components, which are responsible for the unusual high frequency isotropic shift of the 31P resonances. This property correlates inversely with the metal to olefin backbonding (M,C=Ctrop) and ,(31P) decreases with increasing M,C=Ctrop in the order 9 (, = 260 ppm) > 7 (, = 196 ppm) > 6 (, = 135 ppm) > 3 (, = ,30.9 ppm). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Chelating Phosphane,Boranes as Hemilabile Ligands , Synthesis of[Mn(CO)3(,2 -H3B·dppm)][BArF4] and [Mn(CO)4(,1 -H3B·dppm)][BArF4]EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 20 2006Nicolas Merle Abstract Manganese complexes bearing the chelating phosphane,borane ligand H3B·dppm [dppm = bis(diphenylphosphanyl)methane] have been prepared. Addition of H3B·dppm to Mn(CO)5Br using Na[BArF4] as a halide-abstracting reagent affords [Mn(CO)3(,2 -H3B·dppm)][BArF4] (1). This reacts with CO to open the bidentate borane to afford [Mn(CO)4(,1 -H3B·dppm)][BArF4] (2) in which the borane is now bound in a monodentate manner. The CO addition is reversible, and placing 2 under vacuum (hours) regenerates 1 quantitatively, demonstrating that the chelating phosphane,boranes can act as hemilabile ligands. The complexes 1 and 2 have been fully characterised by NMR spectroscopy and X-ray crystallography. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Preparation of Hydroxylamine and O -Methylhydroxylamine Complexes of Manganese and RheniumEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 17 2006Gabriele Albertin Abstract Hydroxylamine and O -methylhydroxylamine complexes [M(NH2OH)(CO)nP5,n]BPh4 and [M(NH2OCH3)(CO)nP5,n]BPh4 [M = Mn, Re; n = 1, 2, 3; P = P(OEt)3, PPh(OEt)2, PPh2OEt] were prepared by allowing hydrides MH(CO)nP5,n to react first with triflic acid and then with an excess of hydroxylamine. Bidentate phosphane and phosphite can also be used to prepare both NH2OH and NH2OCH3 complexes of manganese and rhenium of the [M(NH2OR)(CO)2(P,P)-{P(OEt)3}]BPh4 and [M(NH2OR)(CO)3(P,P)]BPh4 [R = H, CH3; P,P = Ph2POCH2CH2OPPh2, Ph2PO(CH2)3OPPh2, Ph2PN(CH3)CH2CH2N(CH3)PPh2] types with the use of MH(CO)2(P,P){P(OEt)3} and MH(CO)3(P,P) as precursors. The complexes were characterized spectroscopically and by theX-ray crystal-structure determination of [Re(NH2OCH3)(CO)2{PPh(OEt)2}3]BPh4 and [Re(NH2OCH3)(CO)3{Ph2PO(CH2)3OPPh2}]BPh4. Oxidation of the hydroxylamine complexes with Pb(OAc)4 was studied at ,40 °C and led to an unstable compound tentatively characterized as a nitroxyl [M],N(H)=O derivative.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Syntheses and Fluxional Processes of Diphenyl(2-thienyl)phosphane Derivatives of Triosmium ClustersEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 10 2006Nitsa K. Kiriakidou Kazemifar Abstract Thermal treatment of [Os3(CO)12] with diphenyl(2-thienyl)phosphane, Ph2P(C4H3S), results in the formation of [Os3(CO)12,x{Ph2P(C4H3S)}x] (x = 1,3, 1,3), but no C,H bond activation was observed. Reaction of [H2Os3(CO)10] with diphenyl(2-thienyl)phosphane at ambient temperature affords [HOs3(,-H)(CO)10{Ph2P(C4H3S)}] (4), but when the samereaction is repeated at elevated temperatures, the cyclometallated species [(,-H)Os3(CO)9{,3 -Ph2P(C4H2S)}] (5) and[(,-H)Os3(CO)8{,3 -Ph2P(C4H2S)}{Ph2P(C4H3S)}] (6) are formed. In addition, two more products, tentatively assigned as [(,-H)Os3(CO)6{,3 -Ph2P(C4H2S)}{,-Ph2P(C4H3S)}{Ph2P(C4H3S)}] (7) and [(,-H)Os3(CO)7{,-Ph2P(C4H2S)}{,-Ph2P(C4H3S)}{Ph2P(C4H3S)}] (8) are obtained. The dynamic behaviours of 2, 5 and 6 have been studied by variable-temperature (VT) 1H and 31P{1H} NMR spectroscopy. The VT 31P{1H} NMR spectra of [Os3(CO)10{Ph2P(C4H3S)}2] (2) demonstrate that a mixture of two isomers, which are in rapid exchange at room temperature, is present and that the less common cis - trans isomer, whose structure has been determined by X-ray crystallography, is favoured for this cluster. The VT 1H NMR spectra of 5 indicate the presence of two isomers which are proposed to arise from an oscillation of the ,,,2 -vinyl group of the thienyl moiety between two metal atoms. A similar fluxional process is proposed to occur in 6 and the assignment of the room-temperature structure(s) of this cluster was confirmed by 1H- 187Os 2D HMQC spectroscopy. In addition to 2, the solid-state structures of 3, 5 and 6 have been determined by X-ray crystallography. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Density-Functional Calculation of the 183W and 17O NMR Chemical Shifts for Large PolyoxotungstatesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 6 2006Jose Gracia Abstract A phosphane sulfate relativistic DFT method (ZORA)has been used to calculate the 183W and 17O NMR chemicalshifts for large polyoxotungstates, including W6O192,,CH3OTiW5O183,, W5O18WIINO3,, W10O324,, ,-,-,-XW12O40n,, ,-PW9O28Br63,, P2W18O626,, PW2O143,, and W7O246,, based on their optimized molecular structures. Despite sizeable deviations between the calculated and experimental values, the calculations correctly reproduce the trends in the change of the chemical shift for both nuclei. As expected, the diamagnetic term is almost constant throughout the whole series. The change in the chemical shifts is shown to be determined by the paramagnetic term, which depends on the electronic structure of the whole anion under study and, in particular, on the local geometry around a given tungsten atom. On the other hand, there is no correlation between the chemical shift and HOMO,LUMO gap, showing that deeper occupied levels and several unoccupied orbitals play an important role in the paramagnetic term. However, analysis of the components of the paramagnetic shielding has shown that the most significant transitions determining the change of both 183W and 17O NMR chemical shifts for anions consisting of tungsten and oxygen atoms are the occupied,occupied and not the occupied,virtual ones.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Copper Complexes with (2,7-Di- tert -butylfluoren-9-ylidene)methanedithiolate: Oxidatively Promoted Dithioate Condensation,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 1 2006José Vicente Abstract The reaction of [Cu(NCMe)4]PF6 with piperidinium 2,7-di- tert -butyl-9H -fluorene-9-carbodithioate (pipH)[S2C(tBu-Hfy)] (1; tBu-Hfy = 2,7-di- tert -butylfluoren-9-yl), affords [Cun{S2C(tBu-Hfy)}n] (2), which reacts with various P ligands to give [Cu{S2C(tBu-Hfy)}L2] [L = PPh3 (3a), PCy3 (3b), PiPr3 (3d); L2 = 1,1,-bis(diphenylphosphanyl)ferrocene (dppf, 3c), bis(diphenylphosphanyl)methane (dppm, 3e)]. Compounds 3a,c react with atmospheric oxygen and moisture in the presence of NEt3 to give the dinuclear complexes [Cu2{[SC=(tBu-fy)]2S}L2] [tBu-fy = 2,7-di- tert -butylfluoren-9-ylidene; L = PPh3 (4a), PCy3 (4b); L2 = dppf (4c)], which contain a new dithiolato ligand formally resulting from the condensation of two dithioato ligands with loss of a sulfide ion and two protons. Neutral CuI dithiolate complexes of the type [Cu4{S2C=(tBu-fy)}2L4] [S2C=(tBu-fy) = [2,7-di- tert -butylfluoren-9-ylidene)methanedithiolate; L = PPh3 (5a), P(C6H4OMe- p)3 (5b), PiPr3 (5d) or L2 = dppf (5c)] were obtained by treating 1 with [Cu(NCMe)4]PF6, the corresponding phosphane, and piperidine in a 1:2:2:1 molar ratio. The reaction of 1 with Cu(ClO4)2·6H2O and (Pr4N)OH in a 2:1:2 molar ratio gives the CuII complex (Pr4N)2[Cu{S2C=(tBu-fy)}2] [(Pr4N)26], which readily oxidizes to the CuIII complex Pr4N[Cu{S2C=(tBu-fy)}2] (Pr4N7) in the presence of atmospheric oxygen and moisture. The salt PPN7 [PPN+ =(Ph3P)2N+] was obtained from 1, CuCl2·2H2O, PPNCl, and piperidine in a 2:1:1:2 molar ratio under aerobic conditions. The crystal structures of 3a, 3c·CH2Cl2, 4a·4Me2CO, and 4c·CH2Cl2 have been determined by X-ray diffraction studies. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] The Synthesis and Characterisation of Bis(phosphane)-Linked (6 - p -Cymene)ruthenium(II),Borane CompoundsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 23 2005Adrian B. Chaplin Abstract The reaction of [(,6 - p -cymene)RuCl2]2 with some bis(phosphane) ligands (dppm, dppe, dppv, dppa, dpp14b, dppf) has been investigated. In general mixtures of products were obtained, although the pendant phosphane complexes [(,6 - p -cymene)RuCl2(,1 -dppv)] and [(,6 - p -cymene)RuCl2(,1 -dppa)] were isolated and characterized in the solid state by X-ray diffraction. The later complex was obtained in lower yield and undergoes an equilibration reaction resulting in the formation of a dimeric species, where the dppa bridges two ruthenium centres, and uncoordinated phosphane; the bridging species was also structurally characterised in the solid state. In contrast, the reaction of [(,6 - p -cymene)RuCl2(PPh3)] with dppa in the presence of [NH4]PF6 results in the formation of [(,6 - p -cymene)RuCl(PPh3)(,1 -dppa)]PF6, which is stable in solution. A series of linked ruthenium,borane complexes, viz. [(,6 - p -cymene)RuCl2(,1 -phosphane-BH3)] (phosphane = dppm, dppe, dppv, dppa, dpp14b, dppf) and [(,6 - p -cymene)RuCl(PPh3)(,1 -dppa-BH3)]PF6 have been prepared from isolated pendant phosphane complexes, those generated in situ, or from a preformed phosphane,borane adduct. The solid-state structures of [(,6 - p -cymene)RuCl2(,1 -dppm-BH3)], [(,6 - p -cymene)RuCl2(,1 -dppe-BH3)] and [(,6 - p -cymene)RuCl2(,1 -dppv-BH3)] have been determined by X-ray diffraction analysis. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Preparation and Coordination Chemistry of n -AllylaminophosphaneEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 4 2005Alexandra M. Z. Slawin Abstract Reaction of allylamine with 1 equiv. of Ph2PCl in the presence of NEt3, proceeds in THF to give (allylamino)phosphane 1. 1 has been coordinated as a monodentate P ligand with Au, Pd, Pt, Ru, Rh, Ir and as a bidentate P,allyl ligand to Pt. Reaction of KOtBu with [PtCl2{Ph2PNH(C3H5)}2] in methanol gives [Pt{Ph2PNH(C3H8O)}2]. The X-ray structures of 1.Se and four demonstrative monodentate complexes all reveal intramolecular N,H···Cl hydrogen bonding. The structure of [Pt{Ph2PNH(C3H8O)}2] consists of an N,H···O hydrogen-bonded dimer in the solid state. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Structure, Electrochemistry and Hydroformylation Catalytic Activity of the Bis(pyrazolylborato)rhodium(I) Complexes [RhBp(CO)P] [P = P(NC4H4)3, PPh3, PCy3, P(C6H4OMe-4)3]EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 7 2004Anna M. Trzeciak Abstract Rhodium complexes of formula [RhBp(CO)P] [Bp = bis(pyrazolylborate), P = P(NC4H4)31, PPh32, PCy33, P(C6H4OMe-4)34] have been prepared by exchange of the acetylacetonate (acac,) ligand in [Rh(acac)(CO)P] complexes. The spectroscopic and electrochemical properties as well as X-ray data of [Rh(acac)(CO)P] and [RhBp(CO)P] complexes have been compared with the aim to estimate the relative donor properties of both anionic ligands (acac, and Bp,). The cyclic voltammetric results indicate that the Bp, ligand behaves as a much stronger electron donor than acac, and a value of the Lever EL ligand parameter identical to that of the pyrazolate ligand (,0.24 V vs. NHE for each coordinating arm) is proposed for the bis- and tris(pyrazolyl)borate ligands, whereas P(C6H4OMe-4)3 is also shown to have an identical EL value (0.69 V) to that of P(NC4H4)3. An improved linear relationship between the oxidation potential and the sum of the ligand EL values for square-planar RhI complexes is also obtained and adjusted values for the Lever SM and IM parameters for the RhI/RhII redox couple are given. The trans influence of phosphanes was not observed in crystals of complexes 2 and 3, in contrast to analogous acetylacetonato complexes in which the Rh,O bonds differ by ca. 0.04,0.06 Å. Complexes 1,4 are very attractive precursors for hydroformylation catalysts and yields of aldehydes of 80,87% have been obtained with all complexes without extra phosphane as co-catalyst. During the hydroformylation reaction, however, small amounts of a catalytically inactive [RhBp(CO)2] complex were formed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Regiospecific Cyclometalation of Diphenyl(2-substituted phenyl)phosphane with Methyltetrakis(trimethylphosphane)cobalt(I)EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 5 2003Hans-Friedrich Klein Abstract The pre-chelate molecules 2-(diphenylphosphanyl)- N,N -dimethylaniline, [2-(diphenylphosphanyl)benzyl]dimethylamine, 1-(diphenylphosphanyl)-2-ethylbenzene, 1-(diphenylphosphanyl)-2-isopropylbenzene, and 2-(diphenylphosphanyl)benzonitrile, in a reaction with [CoMe(PMe3)4], eliminate methane to afford the selectively 6- ortho -metalated complexes 1,5 that contain four-membered metallacycles. The molecular structure of 3 shows a tbp-coordinated cobalt atom, with axial C and PMe3 donor groups. Metalation in the aliphatic side-chain occurs with 2-(diphenylphosphanyl)toluene, giving complex 6 that contains a five-membered metallacycle. Benzyldiphenylphosphane is selectively ortho -metalated in the benzyl group, affording 7. As shown by the molecular structures, complex 7 is a true ligand isomer of 6. Substitution of a trimethylphosphane group in compounds 4 and 6 by ethene gives the pentacoordinate complexes 8 and 9, respectively. The ethene ligand is ,-coordinated in the equatorial plane of a trigonal bipyramid. Under 1 bar of CO, complex 6 forms monocarbonyl complex 10. Carbonylation of complexes 3 and 4 proceeds by insertion of CO into the Co,C bond under ring expansion, affording the aroylcobalt complexes 11 and 12, respectively. Complex 6 reacts with iodomethane in an oxidative substitution reaction yielding a structurally characterized octahedral complex mer - 13, which eliminates a methyl group in THF at 20 °C to form a pentacoordinate cobalt(II) complex 14. Complex 3 oxidatively adds iodomethane in a stereoselective cis addition to give the cobalt(III) complex mer - 15, which retains its four-membered metallacycle and the CoCH3 group. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Reaction of 1,2-Diaza-1,3-butadienes with Aminophosphorus Nucleophiles: A Practical Access to New Phosphorylated PyrazolonesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 35 2008Orazio A. Attanasi Abstract The reaction of 1,2-diaza-1,3-butadienes with dibenzyl diisopropylphosphoramidite, methyl tetraisopropylphosphorodiamidite or tris(dimethylamino)phosphane under solvent-free conditions gave stable ,-phosphoranylidene-hydrazones that, in turn, were transformed into the corresponding 5-oxo-4-phosphoranylidene-4,5-dihydro-1H -pyrazoles. X-ray diffraction analysis of one of these derivatives is reported. ,-Phosphoranylidene-hydrazones, derived from the reaction between 1,2-diaza-1,3-butadienes with dibenzyl diisopropylphosphoramidite, were converted by hydrolytic cleavage into (E)-hydrazono-phosphonates, which are useful for the preparation of the corresponding (3-oxo-2,3-dihydro-1H -pyrazol-4-yl)phosphonamidates.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Direct Synthesis of Protected Arylacetaldehydes by Tetrakis(phosphane)palladium-Catalyzed Arylation of Ethyleneglycol Vinyl EtherEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 3 2006Isabelle Kondolff Abstract A range of aryl bromides undergo Heck reaction with ethylene glycol vinyl ether, in the presence of [PdCl(C3H5)]2/cis,cis,cis -1,2,3,4-tetrakis[(diphenylphosphanyl)methyl]cyclopentane as catalyst, to give regioselectively protected arylacetaldehydes in good yields. The ,-arylation products were obtained in with 93,100,% selectivity with electron-poor aryl bromides or heteroaryl bromides. Furthermore, this catalyst can be used at low loading, even for reactions with sterically hindered aryl bromides. The aryl vinyl ether intermediates undergo subsequent ketalisation to give the corresponding 2-benzyl-1,3-dioxolane derivatives.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Hydrophobic Chemistry in Aqueous Solution: Stabilization and Stereoselective Encapsulation of Phosphonium Guests in a Supramolecular HostEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 22 2004Julia L. Brumaghim Abstract Encapsulation of guest molecules inside supramolecular host assemblies provides a way to stabilize reactive species in aqueous solution. The stabilization of reactive phosphonium/ketone adducts of the general formula [R1MeC(OH)PR3]+ by encapsulation as guest molecules within a [Ga4L6]12, tetrahedral metal,ligand assembly is reported; although these cations decompose in aqueous solution, encapsulation inside the hydrophobic cavity of the assembly lengthens their lifetimes considerably, in some cases up to weeks. By varying the phosphane (PMe3, PEt3, PPhMe2, and PPh2Me) and ketone (acetone, methyl ethyl ketone, 1,1,1-trifluoroacetone, and fluoroacetone) which form these adducts, as well as the pD of the solutions, it was determined that the pH of the solution as well as the size and shape of the guest cations play an important role in the stability of these host,guest complexes. Encapsulation of chiral guests in the chiral [Ga4L6]12, assembly results in the formation of diastereomers, as characterized by 1H, 19F, and 31P NMR spectroscopy. Although the [Ga4L6]12, assembly is formed from non-chiral ligands, the assembly itself has ,,,, or ,,,, chirality around the metal centers. Due to the chirality of this assembly, diastereomeric selectivity is observed upon initial guest encapsulation (typical diastereomeric excesses are 30,50%). This initial diastereomeric selectivity decreases over time to reach an equilibrium but does not become 1:1, indicating both kinetic and thermodynamic processes promote selective guest encapsulation. These experiments demonstrate further the applications of nanoscale reaction vessels, self-assembled by design from non-chiral ligands, in providing a chiral and hydrophobic environment for guest molecules in aqueous solution. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Palladium-Catalyzed Preparation of Propargylic or Allenylic Sulfides from Propargyl Halides or Mesylate and ThiolsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 3 2004Ken Tsutsumi Abstract In the presence of a catalytic amount of Pd0 -dppe complex [dppe: 1,2-bis(diphenylphosphanyl)ethane], generated in situ from [Pd2(dba)3·CHCl3] and dppe, propargylic bromide 1a reacted with an equimolar amount of propanethiol at 60 °C in DMF to afford propargylic sulfide 2 in an excellent yield. The reaction occurs readily when carried out in the presence of the weak base triethylamine. The choice of both the phosphane, which is employed as the palladium atom's ligand, and the solvent have a remarkable effect on this reaction. We found that the optimum conditions for the reaction are those using a bidentate phosphane ligand (dppe) in a polar solvent (DMF). Compound 1a reacted smoothly with both aromatic (PhSH) and secondary thiols (CySH) in high yields. The reactions with thiols bearing functional groups (OH or Cl) proceeded selectively in good to moderate yields. Primary chlorides 1b,e were readily converted into their corresponding propargylic sulfides 7,10 in high yields. The Pd0 -dppe catalyst was ineffective in the reaction of the bromide 1g bearing a tBu group at the propargylic position, but the reaction of the corresponding mesylate 1h using the Pd0 -DIOP catalyst [DIOP = O -isopropylidene-2,3-dihydroxy-1,4-bis(diphenylphosphanyl)butane] at 100 °C afforded the product 11 in good yield. Allenylic sulfides were obtained from 1g,i. We suggest that a cationic ,3 -type complex may be a more reactive intermediate in this catalytic reaction than neutral ,1 - or ,3 -allenyl/propargylpalladium complexes. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Propyne Iminium Salts and Phosphorus(III) Nucleophiles: Synthesis of (3-Morpholinoallenyl)phosphanes and -phosphane Oxides or 1-(Morpholinopropargyl)phosphanes and -phosphonatesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 11 2003Martin Reisser Abstract Treatment of 4-(1,3-diphenyl-l-propynylidene)morpholinium triflate (1a) with the neutral phosphorus nucleophiles Me3Si,PPh2, Me3Si,P(Ph)C5H11, and Me3SiO,PPh2 affords (3-morpholinoallenyl)phosphanes 4 and 5 and (3-morpholinoallenyl)phosphane oxide 11, respectively. In contrast to these conjugate addition reactions at the ambident propyne iminium moiety of 1a, nucleophilic attack by Me3Si,PEt2 and Me3SiO,P(OEt)2 takes place at the iminium function and gives (1-morpholinopropargyl)phosphane 6 and (1-morpholinopropargyl)phosphonate 12, respectively. Propyne iminium salt 1b reacts with Me3Si,PPh2 to form (3-morpholino-1,3-butadienyl)phosphane oxide 8. The bis(donor)-substituted allene 4 is transformed by oxidation of the phosphorus substituent into the push-pull substituted allenylphosphane oxide 11. Treatment of allene 4 with elemental sulfur results in the formation of betaine 16, which undergoes [3+2] cycloaddition reactions with acetylenic esters to afford 5-benzylidene-4,5-dihydrothiophenes 17 and 18. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Properties and Catalytic Activities of New Easily-Made Amphiphilic Phosphanes for Aqueous Organometallic CatalysisADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 7 2010Michel Ferreira Abstract Mono- and disulfonated amphiphilic versions of triphenylphosphane (PPh3) and cyclohexyl(phenyl)phosphane were easily synthesized from commercial reagents and sulfuric acid. The behaviour of these phosphanes in solution was investigated by surface tension, isothermal titration calorimetry, nuclear magnetic resonance and cryo-transmission electron microscopy. Two different supramolecular assemblies were evidenced according to the degree of sulfonation. The monosulfonated phosphanes formed well organized micelle-like aggregates while the disulfonated phosphanes formed heterogeneous and disorganized vesicle-like assemblies. The efficiency of these amphiphilic phosphanes was evaluated in the aqueous biphasic, palladium-catalyzed cleavage of allyl alkyl carbonates. [source] An in situ Generated Ruthenium Catalyst for the Tishchenko ReactionADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 2-3 2010Marc-Olivier Simon Abstract A simple and efficient catalytic system for the selective dimerization of aldehydes, the Tishchenko reaction, is described. High yields of symmetrical esters were generally achieved using an in situ generated ruthenium catalyst in association with the electron-rich and hindered cyclohexyl(diphenyl)phosphane (CyPPh2) ligand. [source] Synthesis and anticancer activity of chalcogenide derivatives and platinum(II) and palladium(II) complexes derived from a polar ferrocene phosphanyl,carboxamideAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 5 2010í Schulz Abstract The polar phosphanyl-carboxamide, 1,-(diphenylphosphanyl)-1-[N -(2-hydroxyethyl)carbamoyl]ferrocene (1), reacts readily with hydrogen peroxide and elemental sulfur to give the corresponding phosphane-oxide and phosphane-sulfide, respectively, and with platinum(II) and palladium(II) precursors to afford various bis(phosphane) complexes [MCl2(1 -,P)2] (M = trans -Pd, trans -Pt and cis -Pt). The anticancer activity of the compounds was evaluated in vitro with the complexes showing moderate cytotoxicities towards human ovarian cancer cells. Moreover, the biological activity was found to be strongly influenced by the stereochemistry, with trans -[PtCl2(1 -,P)2] being an order of magnitude more active than the corresponding cis isomer. Copyright © 2010 John Wiley & Sons, Ltd. [source] The Influence of Phosphane Ligands on the Versatility of Ruthenium,Indenylidene Complexes in MetathesisCHEMISTRY - A EUROPEAN JOURNAL, Issue 30 2010Julie Broggi Dr. Abstract The aim of the present study is to develop readily available and stable pre-catalysts that could be easily prepared on large scale from simple starting materials. Based on the hypothesis that substitution of classical PCy3 with phosphanes of varying electron-donating properties could be a straightforward manner to improve catalytic activity, a methodical study dealing with the effect of phosphane fine-tuning in ruthenium,indenylidene catalysts was performed. Challenged to establish how the electronic properties of para -substituted phosphane ligands translate into catalyst activity, the versatile behaviour of these new ruthenium,indenylidene complexes was investigated for a number of metathesis reactions. [source] | ||||||||||