Ether-phosphine Ligand Research Articles

Synthesis, physicochemical analysis of two new hemilabile ether-phosphine ligands and their first stable bis-ether-phosphine/cobalt(II) tetrahedral complexes

New tridentate ether-phosphine {P, 2O} and ether-phosphine oxide {OP, 2O} ligands with P and O donor-atoms have been synthesized starting from ClCH2CH(OCH3)2. The oxidation process of Ph2PCH2CH(OCH3)2 to its oxide derivative Ph2P(O)CH2CH(OCH3)2 was monitored by 31P NMR for the first time. The desired ligands and their Co(II) complexes structures were deduced from IR, EA, MS, NMR, UV–Vis., TG/DTG and XRD physical measurements. The tridentate chelating coordination behavior of the ether-phosphine wasn't detected leading only to the mono-dentate coordination mode through the phosphorous atoms to set up a X2Co[η1-Ph2PCH2CH(OCH3)2]2 as final isomer formula (X = Cl or Br). The Cl2Co[η1-Ph2PCH2CH(OCH3)2]2 isomer belongs to complex 1 was supported by single crystal measurement. Polar/non-polar intermolecular short contacts were detected by XRD and Hirshfeld surface theoretical analysis.

X-ray single crystal, spectral, thermal analysis and 31P{1H} NMR of ruthenium(II)/ether-phosphine/1,2-diphenyl-1,2-ethanediamine complexes

Neutral complex 1 and mono-cationic complex 2 were made available using Ph2PCH2CH2OCH3 and 1,2-diphenyl-1,2-ethanediamine ligands. One of the chloride atoms in complex 1 was abstracted by AgOTf to prepare the mono-cationic O–Ru–P closed complex 2. The hemilability of hybrid ether-phosphine ligand in such complexes was monitored by 31P{1H} NMR and confirmed by X-ray single crystal. XRD structure of complex 2 was found to be a Trigonal crystal system with P3 space group and Z = 6.

Hemilability of ether-phosphine in ruthenium(II) complexes: 31P{1H}-nuclear magnetic resonance (NMR), fast atom bombardment-mass spectroscopy (FAB-MS) and extended X-ray absorption fine structure spectroscopy (EXAF) to confirm the open-closed behavior

The hemilability of the ether-phosphine ligand [Ph2PCH2CH2OMe] was recorded during complexes 1 and 2 synthesis. The structures of both 1 and 2 have been deduced from elemental analysis, IR, EXAF, FAB-mass spectrometry, 1H, 13C{1H} and 31P{1H} NMR spectroscopy. One of the chloride atoms in 1 was abstracted using AgOTf reagent to prepare the mono-cationic O-Ru-P closed 2. By treatment complex 2 with excess amount of NH4Cl in 2-propanol complex 1 was re-prepared. FAB-MS, EXAF and 31P{1H}-NMR served to monitor the hemilability of the ether-phosphine in 1 and 2 at RT. Key words: Ru(II) complexes, ether-phosphine, single crystal, hemilability.

Diphenyl(2-propoxyethyl)phosphine

A new 2-(diphenylphosphino)ethyl propyl ether as hemilabile hybrid ether-phosphine ligand [Ph2PCH2CH2OCH2CH2CH3] was made available. The structure of the titled compound was characterized by elemental analysis, IR, 31P-NMR, 1H-NMR, 13C-NMR, UV-visible spectroscopy and EI-MS.

Supramolecular allosteric cofacial porphyrin complexes.

Nature routinely uses cooperative interactions to regulate cellular activity. For years, chemists have designed synthetic systems that aim toward harnessing the reactivity common to natural biological systems. By learning how to control these interactions in situ, one begins to allow for the preparation of man-made biomimetic systems that can efficiently mimic the interactions found in Nature. To this end, we have designed a synthetic protocol for the preparation of flexible metal-directed supramolecular cofacial porphyrin complexes which are readily obtained in greater than 90% yield through the use of new hemilabile porphyrin ligands with bifunctional ether-phosphine or thioether-phosphine substituents at the 5 and 15 positions on the porphyrin ring. The resulting architectures contain two hemilabile ligand-metal domains (RhI or CuI sites) and two cofacially aligned porphyrins (ZnII sites), offering orthogonal functionalities and allowing these multimetallic complexes to exist in two states, "condensed" or "open". Combining the ether-phosphine ligand with the appropriate RhI or CuI transition-metal precursors results in "open" macrocyclic products. In contrast, reacting the thioether-phosphine ligand with RhI or CuI precursors yields condensed structures that can be converted into their "open" macrocyclic forms via introduction of additional ancillary ligands. The change in cavity size that occurs allows these structures to function as allosteric catalysts for the acyl transfer reaction between X-pyridylcarbinol (where X = 2, 3, or 4) and 1-acetylimidazole. For 3- and 4-pyridylcarbinol, the "open" macrocycle accelerates the acyl transfer reaction more than the condensed analogue and significantly more than the porphyrin monomer. In contrast, an allosteric effect was not observed for 2-pyridylcarbinol, which is expected to be a weaker binder and is unfavorably constrained inside the macrocyclic cavity.

Crystal structure of trans-dichloro-1,3-propanediamine-bis[(2-methoxyethyl) diphenylphosphine]ruthenium (II),RuCl2(C3H10N2)(C15H17OP)2

Article Crystal structure of trans-dichloro-1,3-propanediamine-bis[(2-methoxyethyl) diphenylphosphine]ruthenium (II),RuCl2(C3H10N2)(C15H17OP)2 was published on April 1, 2006 in the journal Zeitschrift für Kristallographie - New Crystal Structures (volume 221, issue 1-4).

Syntheses and coordination behaviour of 2-( ortho-phosphinophenyl)-functionalised 1,3-dioxolanes and 1,3-dioxanes towards a [(COD)Rh]-complex fragment – models for immobilised complexes

The syntheses are reported of the ether–phosphine ligands: 2-( ortho-diphenylphosphinophenyl)-1,3-dioxolane ( 1a), 2-( ortho-diisopropylphosphinophenyl)-1,3-dioxolane ( 1b), 2-( ortho-diphenylphosphinophenyl)-1,3-dioxane ( 1c), 2-( ortho-diisopropylphosphinophenyl)-1,3-dioxane ( 1d). Their reaction with [(COD)RhCl] 2 (COD: 1,5-cyclooctadiene) results in the formation of the mononuclear complexes: {chloro(COD)[2-( ortho-diphenylphosphinophenyl)-1,3-dioxolane]rhodium(I)} ( 2a), {chloro(COD)[2-( ortho-diisopropylphosphinophenyl)-1,3-dioxolane]rhodium(I)} ( 2b), {chloro(COD)[2-( ortho-diphenylphosphinophenyl)-1,3-dioxane]rhodium(I)} ( 2c), and {chloro(COD)[2-( ortho-diisopropylphosphinophenyl)-1,3-dioxane]rhodium(I)} ( 2d). The chloride ligands of compounds 2a and 2b were abstracted with TlPF 6, with accompanied insertion of an acetal oxygen atom of the ligands 1a and 1b into the coordination sphere of the metal centre, producing {(COD)[η 2- P, O-2-( ortho-diphenylphosphinophenyl)-1,3-dioxolane]rhodium(I)}PF 6 ( 3a∗PF 6) and {(COD)[η 2- P, O-2-( ortho-diisopropylphosphinophenyl)-1,3-dioxolane]rhodium(I)}PF 6 ( 3b∗PF 6). In contrast the dioxane analogues of 3, 3c∗BF 4 and 3d∗BF 4, were formed by reacting the ligands 1c, 1d with [Rh(COD) 2]BF 4. The ligands 1 and the complexes 2 serve as model compounds for their via acetalation to a polyvinylalcohol resin bound analogues. The complexes synthesised were employed as pre-catalysts in the hydroformylation reaction of 1-octene.

Molecular structure and properties of the rhodium(II) complexes with chemilabile ether–phosphine ligands P(2-MeOC 6H 4) 3 and P(2,6-(MeO) 2C 6H 3) 3

Reactions of dirhodium tetraacetate [Rh 2(O 2CCH 3) 4] with tris(2-methoxyphenyl)phosphine (OMP) yield the oxygen-metallated complexes [Rh 2(μ-OAc) 3{μ-(2-OC 6H 4)P(2-MeOC 6H 4) 2}(HOAc)] ( 1·HOAc) and [Rh 2(μ-OAc) 3{μ-(2-OC 6H 4)P(2-MeOC 6H 4) 2}(NCMe)] ( 1·NCMe). In the case of tris(2,6-dimethoxyphenyl)phosphine (DOMP) analogous compound [Rh 2(μ-OAc) 3{μ-(2-O-(6-MeO)C 6H 3)P(2,6-(MeO) 2C 6H 3) 2}(HOAc)] ( 2·HOAc) was obtained. In both ligands the CH 3 + cation of one of the methoxy substituents is split off and the phosphine replaces one of the acetato bridges to form the bridge with Rh 2 4+ core closing the six-member ring via P and O atoms. The compounds have been characterized using UV–vis, IR, 1H-, 13C{ 1H}- and 31P{ 1H}-NMR spectroscopies. The crystal structure of compound 1·NCMe has been determined. The Rh(1)Rh(2) distance is distinctly longer than that in [Rh 2(OAc) 4(H 2O) 2] ( 3·2H 2O). Axial sites of dirhodium core are occupied by a molecule of acetonitrile and a methoxy group of one of the nonmetallated phenyl rings. Detailed NMR studies reveal dynamic properties of complex 1 involving exchange between axial methoxy substituents and tilting of the metallated ring. The complexes 1 and 2 react with carbon monoxide giving complexes with a CO ligand coordinated in axial coordination sites.

Reactivity and chemical exchange processes of bis(ether-phosphine) iridium(III) complexes

The orthometalated iridium(III) complex ▪ ▪ coordination of Cy 2PCH 2CH 2OCH 2, ▪coordination of Cy 2PCH 2CH 2OCH 3) (1) reacts with CS 2, HCl and H 2 under re-formation of the methoxy group to give Cllr( ν 2-CS 2) (P∼O) 2 ( 3) (P ∼ O = ν 1( P) coordination of Cy 2PCH 2CH 2OCH 3, ▪ ( 4a) and ▪ respectively. Upon the reaction of 1 with CO the orthometalation is maintained to yield the carbonyl adduct ▪ Compounds 4a and 5 represent potentially unsaturated species weakly protected by the ether moiety which acts as an intramolecular solvent. The chelated five-membered ring in 4a, ▪ ( 4b) and 5 can easily be cleaved by carbon monoxide, pyridine and CS 2 whereby the complexes Cl 2IrH(CO)(P∼O) 2 ( 7), CllrH 2(C 5H 5N)(P∼O) 2 ( 10), CllrH 2(CO)(P∼O) 2 ( 11) and the dithioformato complex cis-(P∼O) 2Ir(H)S 2CH) ( 13a) are formed. In toluence 13a isomerizes to give the trans-product 13b. Comparative NMR studies on the fluxional behavior of the ether phosphine ligands of the five monochelated complexes 4a,b,5, IrH 3( P∼ O) 2( 6) and ▪ were performed to determine the dependence of the exchange rates on the strength of the iridium-(ether)oxygen bond. Complex 9b, the phenyl congener of 9a, crystallizes in the orthorhombic space group Pna2 1 with Z = 4. The cell dimensions are a = 1695.2(3), b = 1093.4(2), c = 1621.5(9) pm, R 1 = 0.018 and wR 2 = 0.042.

Different reactivity of the Ru–O bond in the chelated [(methoxyethyl)diphenylphosphine]ruthenium(II) complexes [( η6-C 6Me 6)Ru(P ∩O)X][BR 4] in dependence on X=Cl and CH 3

Treatment of the starting complexes [( η 6-C 6Me 6)Ru(P~O)X 2] (X=Cl ( 1), CH 3 ( 2); P~O= η 1 (P)-coordinated ether-phosphine ligand Ph 2PCH 2CH 2OCH 3) with NaBPh 4 and HBF 4, respectively, lead to the chelated complexes [( η 6-C 6Me 6)Ru(P ∩O)X][BR 4] (X=Cl ( 3a), CH 3 ( 3b); R=Ph ( 3a), F ( 3b); P ∩O= η 2 (O,P)-coordinated ligand). The rupture of the Ru–O bond in 3a, b with carbon monoxide and acetonitrile results in the formation of the corresponding complexes [( η 6-C 6Me 6)Ru(CO)(P~O)X][BR 4] ( 4a, b) and [( η 6-C 6Me 6)Ru(CH 3CN)(P~O)X] [BR 4] ( 5a, b). The structure of 4a was determined by single-crystal X-ray diffraction. In a similar way the cleavage of the Ru–O bond is achieved when 3a is reacted with tert-butyl isocyanide and 3b with ethene to give the adducts [( η 6-C 6Me 6)Ru(CN tBu)(P~O)Cl][BPh 4] ( 6a) and [( η 6-C 6Me 6)Ru( η 2-C 2H 4)(CH 3)(P~O)][BF 4] ( 7b). All compounds are obtained in excellent yields and under mild conditions.

Dynamic, reactivity and catalytic behavior of pseudo-undercoordinated ruthenium and rhodium complexes stabilized by intramolecular solvents

The fluxional behavior of pseudo-undercoordinated ruthenium complexes provided with bifunctional ether-phosphine ligands which compete for a common coordination site at the metal center is reviewed. The quantitative determination of this dynamic exchange by temperature-dependent 31 P NMR spectroscopy and line-shape analyses gives access to kinetic and thermodynamic data. From these, valuable information concerning the different chelating abilities of various ether-phosphines is available in dependence on both O-nucleophilicity and phosphorus basicity. Based on these experimental results, appropriate (ether-phosphine)-ruthenium and rhodium complexes are presented showing high reactivity toward the activation of small molecules like hydrogen, sulfur dioxide, carbon dioxide, carbon disulfide, ethene and phenylacetylene. Moreover, their catalytic properties with respect to hydrogenations, carbonylations and carbon dioxide hydrogenation are discussed.

Reactivity of the RuO bond in η2(O,P)-chelated mono(ether-phospine) (pentamethylcyclopentadienyl) ruthenium(II) complexes

By treatment of the 16-electron starting compound Cp ∗RuCl ( P ∼ O) ( 1) ( Cp ∗ = η 5− C 5 Me 5; P ∼ O, η 1( P)- coordinated ether-phosphine ligand Cy 2PCH 2CH 2OCH 3) with L = CO ( a) and P(OEt) 3 ( b), the carbonyl and mixed bisphosphine ruthenium(II) complexes Cp ∗ RuCl( L)( P ∼ O) ( 2a, 2b) are accessible. Chloride abstraction from 2a, 2b with NaBPh 4 leads to the chelated complexes [Cp ∗Ru(L)(P ⋒ O)][BPh 4] ( 3a, 3b) (P ⋒ O, η 2(O,P)-coordinated ligand). Cleavage of the RuO bond in 3a, 3b with sulphur dioxide results in the formation of the η 1-SO 2 complexes [ Cp ∗ Ru( L) ( P∼ O)(η 1- SO 2)][ BPh 4] ( 4a, 4b) in which the O 2SRu fragment adopts a trigonal planar geometry. In a similar way the RuO bond is easily ruptured when [Cp ∗Ru(CO)(P ⋒ O)][BPh 4] ( 3) is reacted with ethene and phenylacetylene to give the adduct [ Cp ∗ Ru( CO)( P ∼ O)(η 2- C 2 H 4)][BPh 4] ( 5a) and the η 1-vinylidene complex ( Cp ∗ Ru( CO)( P ∼ O)( C CHPh)][ BPh 4] ( 6a) respectively.

Synthesis, Reactivity, and Structural Characterization of Octahedral Ruthenium(II) Complexes with Small Molecules Containing Hemilabile Ether-Phosphine Ligands

Synthesis, Reactivity, and Structural Characterization of Octahedral Ruthenium(II) Complexes with Small Molecules Containing Hemilabile Ether-Phosphine Ligands

Synthesis and fluxional behaviour of (cyclopentadienyl) and (pentamethylcyclopentadienyl)ruthenium(II) complexes with hemilabile ether-phosphines. 31P DNMR spectroscopic studies and line shape analysis

A series of Cp *RuCl(P∼O) 2 complexes ( 3a-e) (Cp * = η 5-C 5Me 5) were prepared in situ by reaction of [Cp *RuCl 2] n (1) with the ether-phosphine ligands Ph 2PCH 2-D ( 2a-e) (D = CH 2OCH 3 ( a), 1,3-dioxolane-2-yl ( b), 1,3-dioxane-2-yl ( c), 1,3-dioxepane-2-yl ( d), tetrahydrofuran-2-yl ( e)) in the presence of zinc. Treatment of 3a-e and CpRuCl(P ∼ O) 2 ( 4b,c) with AgSbF 6 and NaBPh 4, respectively, afforded cationic, monochelated ruthenium(II) complexes of the type [η 5-C 5R 5)Ru(P ∼ O)(P ⌢ O)] + ( 5a-e: R = CH 3; 6b,c: R = H). The fluxional behaviour of 5a-e and 6c was studied by temperature dependent 31P NMR investigations. In the case of 5a-e computer-generated spectra were fitted to the experimental by using DNMR5. Thermodynamic parameters Δ H≠, Δ S≠ and Δ G≠ were obtained via graphic application of the Eyring equation to the kinetic data. Stirring 5c, 6c under an atmosphere of carbon monoxide results in the formation of [(η 5-C 5R 5)Ru(CO)(P ⌢ O) 2][SbF 6] ( 7c: R = CH 3; 8c: R = H).

Synthesis of new (cyclopentadienyl)rutheniumphosphine complexes with hemilabile ether-phosphines. The X-ray structure of (η 5-C 5H 5)RuCl(Ph 2PCH 2CH 2OCH 3) 2

The reaction of CpRuCl(PPh 3) 2 (Cp=η 5-C 5H 5) with excess ether-phosphine ligand (O,P=Ph 2PR, where R is ether containing alkyl chain) in toluene or n-heptane leads to the mixed complexes CpRuCl(PPh 3)(P∼O) 2 and/ or the bis(ether-phosphine) complexes CpRuCl(P∼O) 2. A single X-ray structure determination has been carried out for CpRuCl(Ph 2PCH 2CH 2OCH 3) 2 ( 4a): space group P 1 , a=9.2806(6), b=11.9454(8), c=15.2216(9) Å, α=84.482(9), β=74.592(5), γ=85.066(8)°, V= 1616.1(3) Å 3, F(000)=712, D x=1.42 g cm −3, Z=2, R=0.064, R w=0.075. Treatment of 4a with AgSbF 6 affords the salt [CpRu( PO )(P∼O)][SbF 6] ( 5a), with one mono- (P∼O) and one bidentate coordinating ( PO ) ether-phosphine ligand. The fluxional behaviour of the cation of 5a has been studied by temperature dependent 31p{ 1H} NMR investigations. Stirring 5a under an atmosphere of carbon monoxide resulted in the formation of [CpRu(P∼O) 2(CO)][SbF 6] ( 6a). All complexes have been characterized by 1H, 31P{ 1H}, 13C{ 1H} NMR, IR, mass spectroscopy and elemental analysis.

Ruthenium(II)-Komplexe mit dem neuen Liganden (Oxetanyl-2-methyl)diphenylphosphan / Ruthenium(II) Complexes with the Novel Ligand (Oxetanyl-2-methyl)diphenylphosphine

The new ether-phosphine ligand (oxetanyl-2-methyl)diphenylphosphine (1) with strongly basic properties is obtained by reaction of LiPPh2 with 2-chloromethyloxetane. Reaction of 1 with Cl2Ru(PPh3)3 results in the formation of the bis(chelate) complex trans-Cl2Ru(P~O)2 (2). (P∼O = η1-P-coordinated; P~O = η/2-O,P-coordinated). With CO only one Ru-O bond is cleaved to give the monocarbonylruthenium(II) complex trans-Cl2Ru(CO)(P∼O)(P~O) (3). 3 shows fluxional behaviour only at higher temperatures as demonstrated by 31P{1H} NMR spectra.

New Applications of Weak Donor Atoms to Coordination, Organometallic and Materials Chemistry

Abstract Non-aqueous solvated transition metal cations are enjoying renewed popularity as precursors for new applications in molecular and materials chemistry. In two related projects, we are engaged in a general investigation of the syntheses, structures and reactivity of new compounds containing nitrile and ether ligands. A major effort is underway to synthesize homoleptic metal-metal bonded acetonitrile cations of second and third row metals for use in coordination and organometallic chemistry, photochemistry and materials chemistry. Dinuclear carboxylate, halide and halide-phosphine complexes are used to synthesize the metal-metal bonded acetonitrile cations [M2(MeCN)10]4+ (M = Re, Rh). The unusual partially solvated species [Mo2 IV,IV(μ-F)(MeCN)8O2]3+ was prepared from MoCl3(THF)3 in CH3CN. Reactions of the bulky ether-phosphine ligand tris(2,4,6-trimethoxyphenyl)phosphine (TMPP) with the dinuclear cation [Rh2(MeCN)10]4+ and with acetonitrile cations of 3d metals [M(MeCN)6]2+ (M = Co, Ni) produce bis...

Neuartige basische Liganden für die homogenkatalytische Methanolcarbonylierung, XXXI Kationische Bis(Ether-Phosphan)metall-Komplexe der Nickeltriade mit fluktuierendem Verhalten / Novel Basic Ligands for the Homogeneous Catalytic Methanol Carbonylation, XXXI Cationic Bis(Ether-Phosphine)Metal Complexes of the Nickel Triad with Fluxional Behavior

The (ether-phosphine) ligands R2PCH2C5H9O (1a-c) [R = Ph (a), Cy (= cyclo-C6H11) (b), n-C3H7 (c); C5H9O = tetrahydropyranyl] are obtained from the corresponding alkali metal phosphides MPR2 (M = Li, Na) and 2-chloromethyltetrahydropyran in ether. Reaction of 1 a-c with either Cl2M(COD) (COD = 1,5-cyclooctadiene) or [Ni(OH2)6]Cl2 in a2:1 ratio leads to the bis(ether-phosphine)metal complexes Cl2M(R2P∾O)2 trans-2b,c, trans-3b, cis-2a,b, cis-3a, and 4a [M = Pd (2), Pt (3), Ni (4)], in which the ligands 1a-c are η1-P-coordinated. In 2—4 Cl- is abstracted by AgClO4 to give the cationic trans-bis(ether-phosphine) complexes [ClM(R2P ∾ O)(R2P~O)][ClO4] (5a, 6a-c, 7a) [M = Ni (5), Pd (6), Pt (7); P∾O = η1-P-coordinated; P~O = η2-O,P-coordinated]. In contrast to 7a, the nickel and palladium complexes 5a and 6a-c show fluxional behavior as demonstrated by temperature dependent 31P{1H} NMR spectra. The coalescence temperatures and estimated free energie enthalpies ΔG≉ of 5a and 6a-c are compared with the corresponding data of the complexes [ClPd(Ph2P ∾ O)(Ph2~O)][ClO4] (8a-10a) [O,P ligand = Ph2PCH2C4H7O (8a), Ph2PCH2C4H7O2 (9a), Ph2PCH2CH2OCH3 (10a)] and give an insight into the relative basicity of the ether oxygen atoms.

Fluxional behaviour of bis- and tris-(ether phosphine)ruthenium(II) chloro and acetato complexes

The syntheses of bis- and tris-[(2-methoxyethyl)diphenylphosphine]ruthenium(II) complexes with chloro, acetato, and trifluoroacetato ligands are described. The complexes are mer-[RuCl2(P–O)(PO)2], fac-[RuCl(P–O)2(PO)]X (X = Cl, SbF6, or BPh4), fac-[Ru(P–O)3][SbF6]2, [RuCl(P–O)2]SbF6, fac-[Ru(O2CCH3)2(PO)3], fac-[Ru(O2CCH3)(P–O)(PO)2]X (X = O2CCH3 or BPh4), [RuX2(O,P)2](X = O2CCH3 or O2CCF3), [RuCl(O2CCH3)(O,P)2] and mer-[RuH(O2CCH3)(PO)3]; PO represents the ligand which is co-ordinated via phosphorus only (ether function free), P–O ligand which is co-ordinated in the bidentate chelating mode via phosphorus and oxygen, and O,P is used where the mode of co-ordination is not certain. The mechanism of the fluxional behaviour of these complexes in solution has been investigated by the use of temperature-programmed 31P and 13C n.m.r. and by nuclear Overhauser enhancement spectroscopy 31P n.m.r. studies. Fluxional processes occur through exchange between the bidentate (P- and O-bonded) and the monodentate (P-bonded) co-ordination modes of the ether phosphine ligands, as the labile metal–oxygen bonds are broken and reformed. A second type of fluxional process is observed in the six-co-ordinate tris(ether phosphine) complexes due to Berry-type rearrangements of five-co-ordinate intermediates formed upon opening of a metal–oxygen bond. In several of the complexes both types of fluxional process are operating simultaneously. Other complexes show different types of fluxional behaviour in polar and in non-polar solvents, due to ionic dissociation of chloride and acetate ligands in the polar solvents. Some reactions of the complexes are also discussed.

Neuartige basische Liganden für die homogenkatalytische Methanolcarbonylierung: XIII. Kationische Ether-Phosphan-Ruthenium(II)-Komplexe als potentielle katalysatoren zur homogenen Hydrierung von Aldehyden

Depending on the ether phosphine ligand used viz. Ph 2PCH 2C 4H 7O ( a) or cyclo-(C 6H 11) 2PCH 2CH 2OCH 3 ( b), Cl − abstraction from trans-Cl 2(OC)Ru( PO )-(P ∼ O) ( 1a,1b) results in the formation of the cationic complex [ cis-Cl(OC)-Ru( PO ) 2][SbF 6] ( 2a) or [ trans-Cl(OC)Ru( PO ) 2][SbF 6] ( 2b), respectively. 2a and 2b are of potential catalytic interest for hydrogenation reactions. 31P{; 1H}; NMR studies on solutions of 2a reveal that only one Ru-O bond is present, which is in contrast to the solid.