Magriet J. Nolte

Formation of cationic and neutral carbamato and related ruthenium(II) complexes from reaction of CO2, COS and CS2 with ruthenium hydrides in alcohol solution containing HNMe2. The crystal structure of [Ru(O2CNMe2)(PMe2Ph)4]PF6

The salts [Ru(XYCR)(PMe2Ph)4]PF6 (XY = OS, R = OEt; XY = S2, R = H), [Ru(XYCNMe2)(PMe2Ph)4]PF6 (XY = O2, OS, S2) and the neutral product [RuH(O2CNMe2)(PPh3)3] are formed by interaction of CO2, COS or CS2 with [RuH(PMe2Ph)5]PF6 or [RuH2(PPh3)4] in ethanol or ethanol/dimethylamine mixtures; the crystal structure of [Ru(O2CNMe2)(PMe2Ph)4]PF6 has been determined.

Conversion of bonded cyclo-octadiene into a cyclo-octadienyl ligand and cleavage of boron–phenyl bonds of arene-bonded tetraphenylborate anions in ruthenium(II) systems: X-ray crystal and molecular structures of [Ru(η6-C6H5BL3)(1–3,5,6-η-C8H11)](L = Ph or F)

Labilisation of the hydrazine ligands in either [Ru(cod)(N2H4)4][BPh4]2(I; cod = cyclo-octa-1,5-diene) or [RuH(cod)(NH2NMe2)3][BPh4](II) in acetone produces [Ru(η6-C6H5BPh3)(1–3,5,6-η-C8H11)] which reacts with HA (A = BF4 or PF6) to give [Ru(η6-C6H5-BF3)(1–3,5,6-η-C8H11)]; a byproduct of the reaction with (II) is [Ru(cod)(C6H6)].

Structural studies of substituted hydrazine complexes. Part 3. Crystal and molecular structure of dichlorobis(η-cyclo-octa-1,5-diene)-(NN-dimethylhydrazine)dihydridodiruthenium, an asymmetric triply bridged dimer containing a bidentate bridging NN-dimethylhydrazine ligand

Crystals of the title complex are monoclinic, space group P21/c, with unit-cell dimensions a= 17.99(2), b= 7.46(2), c= 20.91(2)A, and β= 133.8(1)°. A final R of 0.073 for 1 487 observed reflections has been obtained. The molecule is a highly distorted dimer with the two ruthenium atoms bridged by H–, Cl–, and NH2NMe2 ligands. Terminal chloride and hydride ligands are situated trans to, respectively, the bridging H– and Cl– ligands, and an η-cyclo-octa-1,5-diene is co-ordinated to each ruthenium atom. The methyl-substituted nitrogen is bonded to the ruthenium which carries the terminal H– ligand. A unique structural feature is the bidentate bridging NH2NMe2 ligand: Ru–NH2 2.12, Ru–NMe2 2.24, and N–N 1.51 A; Ru–NH2–N 115 and Ru–NMe2–N 103°. The Ru⋯Ru distance (2.91 A) indicates the presence of a metal–metal bond of order one.

Crystal and molecular structure of [IrP{(OC6H3Me)2(OC6H4Me)}Cl(γ-picoline)2] formed by the ortho-cyclometallation of two ortho-tolyl groups on a single tri-ortho-tolylphosphite ligand

Abstract The title molecule crystallizes in the monoclinic space group P21/c with a 9.12(2), b 17.36(2), c 20.65(2)Aand β 90.5(1)°. The structure was solved by Patterson and Fourier methods and refined by least-squares, using 2583 reflections, to R 0.04. The structure consists of independent monomeric units. The iridium atom is in a distorted octahedral environment with one phosphorus, two ortho carbon atoms of two o-tolyl groups, one chloride ion and two nitrogens from two γ-picoline ligands occupying the octahedral positions. Metal—ligand bond lengths observed are Ir Cl 2.44, Ir P 2.14, Ir C 2.04 and 2.05, and Ir N 2.17 and 2.17A. Bond angles related to the chelate rings are discussed as are other relevant parameters in the structure.

The O–O bond length in oxygen adducts of iridium and rhodium complexes

The O–O bond length in dioxygen complexes of Rh and Ir compounds lies in the range 1·45–1·50 A; the long bond of 1·625 A reported for [IrO2(dppe)2]+ is an artefact caused by crystal decomposition.

Structural studies of substituted hydrazine complexes. Part 2. Crystal and molecular structure of (η-cyclo-octa-1,5-diene)tris(NN-dimethylhydrazine)hydroruthenium(II) hexafluorophosphate

The crystal and molecular structure of the title complex has been determined by X-ray diffraction methods from counter data. The colourless crystals, M= 535.6, are monoclinic with space group P21/n, a= 14.96(2), b= 16.34(2), c= 9.78(2)A, β= 92.6(1)°, and Z= 4. The structure has been solved by the heavy-atom method and refined by least-squares to R 0.063 for 1 780 observed reflections (graphite-monochromatized Mo-Kα radiation). The co-ordination geometry of the cation is approximately octahedral with the six sites occupied by a bidentate cyclo-octa-1,5-diene ligand, a hydride ligand (unlocated), and a fac configuration of NH2NMe2 ligands, bonded to the ruthenium via NH2 nitrogen atoms. The bond from ruthenium to the nitrogen atom trans to the hydride ligand [2.28(1) A] is significantly longer than those to the other two co-ordinated nitrogen atoms [mean 2.19(1)A;]. The small N–Ru–N angles (82, 84, and 86°), short non-bonded distances between the NH2 and NMe2 nitrogen atoms (2.87, 2.89, and 2.93 A), and the symmetrical arrangement of the hydrazine ligands are indicative of hydrogen bonding between these ligands.

Synthesis and crystal structures of 7-acetamido-7,8-di-deoxy-1,2:3,4-di-O-isopropylidene-β-L-threo-Dgalacto-octopyanose and 7-acetamido-6-O-acetyl-7,8-dideoxy-1,2:3,4-di-O-isopropylidene-α-D-erythro-D-galacto-octopyranose

Abstract 7-Acetamido-7,8-dideoxy-1,2:3,4-di- O -isopropylidene-α- D -erythro- ( 14 ) and -threo- and -β- L -erythro- and -threo- ( 17 ) octopyranose, intermediates for the synthesis of analogs of the antibiotic lincomycin, have been synthesized from a mixture of 7,8-dideoxy-7-C-nitro-octoses prepared from D -galactose. O -Acetylation of 14 gave the 6-acetate ( 18 ). The configurations of C-6 and C-7 in compounds 17 and 18 were determined by X-ray crystallography. The crystals of compound 17 are monoclinic, space group C2, with Z  4, in a unit cell of dimensions a  1.825(1) nm, b  947(1) pm, and c  1.123(1) nm. The crystals of compound 18 are orthorhombic, space group P2 1 2 1 2 1 , with Z  12, in a unit cell of dimensions a  2.814(2) nm, b  1.302(1) nm, and c  1.713(1) nm.

Synthesis of cationic carbonyl cyclopentadienyl complexes of molybdenum and tungsten, and X-ray crystal structure of (acetone hydrazone)-tricarbonyl(η-cyclopentadienyl)tungsten hexafluorophosphate

Substitution of the hydrazine ligand in [Mo(η-C5H5)(CO)3(N2H4)]Cl with a range of commonly used tertiary phosphine and phosphite ligands (L) has provided a new high-yield route to [Mo(η-C5H5)(CO)3L]+ cations for the majority, but not all, of the ligands used. With phosphonites, phosphinites, and smaller phosphines there is a competing reaction to give [Mo(η-C5H5)(CO)2L2]+ cations. Reaction of [W(η-C5H5)(CO)3(N2H4)] Cl with PPh3and PMePh2 gives [W(η-C5H5)(CO)3L]+(L = PPh3 or PMePh2) and [W(η-C5H5)(NCO)(CO)2(PPh3)], depending on the reaction conditions. The complexes [M(η-C5H5)(CO)3(N2H4)]Cl (M = Mo or W) react with acetone to give the respective hydrazone cations [M(η-C5H5)(CO)3(NH2NCMe)]+, which are thermodynamically more stable than the hydrazine precursors; [Mo(η-C5H5)(CO)3(NH2NCMe2)]+ is converted into [Mo(η-C5H5)(CO)2-(solvent)2]+ in-polar solvents at room temperature. The crystal and molecular structure of [W(η-C5H5)(CO)3-(NH2NCMe2)][PF6] has been determined from three-dimensional X-ray data collected by counter methods. The structure has been refined by full-matrix least-squares techniques to a final R(on F) of 0.030, based on 2 141 reflections. The complex crystallises in the triclinic space group P with two molecules in a cell of dimensions a= 10.81 (2), b= 9.74(2), c= 8.47(2)A, α= 113.3(1), β= 96.0(1), and γ= 95.1 (1)°. The tungsten atom is formally seven co-ordinate and the complex is best described as possessing the ‘piano-stool’ geometry. The major feature is the mode of bonding of the hydrazone ligand, which is shown to occur through the amino-nitrogen atom, in contradiction to current theories on the bonding of hydrazones to transition metals. Possible factors in-fluencing the relative stability of amino- or imino-nitrogen bonding are discussed.

Crystal structure of trans-bis(acetone hydrazone)tetrakis(trimethyl phosphite)ruthenium(II) bis(tetraphenylborate) : stabilisation of metal–hydrazone complexes through hydrogen bonding

The crystal structure of the title compound has been determined by X-ray diffraction methods from counter data. Crystals are triclinic, space group P, with Z= 1, a= 15·30, b= 11·54, c= 13·74 (±0·01)A, α= 92·55°, β= 59·02°, γ= 64·49°(±0·01). The structure was solved by heavy-atom methods and refined by least-squares to R 0·069 for 5696 observed reflections. The ruthenium atom has almost ideal octahedral symmetry and the two hydrazone ligands are trans-oriented. Hydrogen bonding between the N-hydrogen of the hydrazone and the oxygen of the phosphite was inferred from observed N–O distances of 2·82 (1) and 2·85 (1)A. Mean Ru–P, Ru–N, and N–C distances are 2·35, 2·17, and 1·28 A.

Tridentate dimetallated phosphiteiridium complexes. The crystal structure of H3 CH3)2 (OC6H4 CH3)(γ-picoline)2]

Abstract [Ir 2 Cl 2 {P(O-o-tolyl) 3 }3] has been prepared from [CODIrCl] 2 2 and o -tolylphosphite in boiling xylene, and shown to be a novel precursor for a series of neutral and cationic tridentate dimetallated phosphite ixidium(III) complexes.