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W2NCl7 has been prepared by the reaction of tungsten pentachloride with the bromide of Millon's base, [Hg2N]Br, in boiling CCl4. The product forms a dark brown, moisture sensitive crystal powder (μeff = 0.7 B.M. at 21 °C). With phosphoryl chloride, the complex W2NCl7·2 POCl3 is formed. The reaction with chlorine leads to the mixed-valenced W(V)/W(VI) complex W2NCl8 (μeff = 0.5 B.M. at 22 °C), which reacts with tetraphenylphosphonium chloride in CH2Cl2 to form (PPh4)2[W2NCl10] ·2CH2Cl2. The reactions of W2NCl7 with PPh4Cl in molar ratios in CH2Cl2 solution lead to several complexes; one of them was identified bv X-ray diffraction methods to be (PPh4)2[W3Cl9(μ3-N)(0)(μ2-NCl)]2 ·1,5 CH2Cl2, which forms black crystals. The compound crystallizes monoclinically in the space group P21/n with two formula units per unit cell (7318 observed, independent reflexions, R = 0.083). The lattice dimensions are (20 °C): a = 994.4; b = 2673; c = 1518.2 pm; β = 101.00°. The compound consists of PPh4⊕ cations and centrosymmetric anions [W3Cl9(μ3-N)(O)(μ2-NCl)]22⊕. The tungsten atoms form a scalene triangle with WW bond lengths of 282 and 278 pm, respectively. The hypothenuse of this triangle is a nearly linear W - N -W bridge with WN distances of 199 and 182 pm. One of the WW edges is bridged by a μ-NCI group with WN bond lengths of 196 und 189 pm. respectively.
Zur Reaktion von [(η3-C4H7)PdCl]2 mit Se(SiMe3)2. Die Kristallstruktur von [(η3-C4H7)6Pd6Se3]
(1988)
[(η3-C4H7)PdCl]2 reacts with Se(SiMe3)2 to form [(η3-C4H7)6Pd6Se3] (1). 1 has been characterized by X-ray crystal structure analysis. It contains a distorted trigonal prismatic Pd6-cluster. Three faces of the Pd-prism are occupied by μ4-Se ligands. 1 crystallizes in the space group Pnma with 4 formula units per unit cell. The lattice constants at 200 K are: a = 1175.1(8), b = 1611.4(12), c = 1720.3(12) pm.
(η5-C5H5)Fe(CO)2Br reacts with Se(SiMe3)2 to form the title compound 1, which has been characterized by X-ray crystal structural analysis. 1 crystallizes in the space group P212121 with 4 formula units per unit cell. 1 consists of [Se{Fe(CO)2(C5H 5)}3]+- cations and [Fe4Se4Br4]2--anions, the latter with a heterocubane structure.
Triphenylmethylphosphonium nitrite and formate have been prepared by the reaction of [PPh3Me]I with silver nitrite, and lead formate, respectively, in aqueous solutions. [PPh3Me]NO2 (1) forms pale yellow crystals, and [PPh3Me]HCO2·H2O (2) forms white crystals. Both compounds are soluble in water, ethanol, and dichloromethane. In moist air 2 is hydrated to yield [PPh3Me]HCO2·2H2O (3). The compounds were characterized by their IR spectra, 1 and 2 also by X-ray crystal structure determinations.
[PPh3Me]NO2 (1): space group P21/n, Z = 4, 2088 independent observed reflexions, R = 0.062. Lattice dimensions (20 °C): a = 914.7(3), b = 1887.5(9), c = 1080.0(4) pm, β = 110.29(3)°. The compound consists of PPh3Me+ ions and NO2- anions with bond lengths of 114.2(6) pm and a bond angle of 124.1(7)°.
[PPh3Me]HCO2·H2O (2): space group P21/n, Z = 4, 2973 independent observed reflexions, R = 0.069. Lattice dimensions (-20 °C): a = 931(2), b = 1558(3), c = 1281(2) pm, β = 105.9(1)°. The compound consists of PPh3Me+ ions and formate anions which form centrosymmetric dimeric units [HCO2·H2O]22- through hydrogen bridges of the water molecules. Bond lengths CO 122.4(4) and 120.9(4) pm. bond angle OCO 129.9(4)°.
[Na-15-crown-5][WF5(NCl)] has been prepared as yellow crystals by the reaction of NaF with WC14(NCl) in the presence of 15-crown-5 in acetonitrile solution. The compound was characterized by its IR spectrum as well as by an X-ray structure determination. Crystal data: space group P 21/n, Z = 4 (2945 observed, independent reflexions, R = 0.035). Lattice dimensions at - 65 °C: a = 827.2(8); b = 1617.3(13); c = 1372.2(10) pm; β = 99.42(5)°. The com pound forms ion pairs, in which the sodium ion is seven-coordinated by the oxygen atoms of the crown ether m olecule, and by two fluorine ligands of the [WF5(NCl)]- unit with Na -F distances of 228.3(6) and 251.3(6) pm. The W ≡ N-Cl group of the anion is nearly linear (bond angle 176.1(5)°) with bond lengths WN = 173.3(6) and NCI = 162.2(7) pm.
[Na-15-Crown-5][MoF5(NCl)] has been prepared as yellow crystals by the reaction of NaF with MoF4(NCl) in the presence of 15-crown-5 in acetonitrile solution. The compound was characterized by its IR and 19F NMR spectra as well as by an X-ray structure determination. Crystal data: space group P21/n, Z = 4 (3736 observed, independent reflexions, R = 0.034). Lattice dimensions at -70 °C: a = 823.5(4). b = 1612.2(9), c = 1383.4(8), β = 99.35(3)°. The compound forms ion pairs, in which the sodium ion is seven-coordinated by the oxygen atoms of the crown ether molecule and by two fluorine ligands of the [MoF5(NCl)]- unit with Na-F distances of 228.3 and 249.6 pm. The Mo=N-Cl group of the anion is nearly linear (bond angle 175.8°) with bond lengths MoN = 172.9 and NCl = 161.8 pm.
The title compound has been prepared from (PPh4)2[Mo2(O2C-Ph)4Cl2] and CCl4 in CH2Cl2 solution as moisture sensitive crystals, which are black in reflexion and yellow in transmission. (PPh4)2[Mo2(O2C-Ph)4Cl4] · 2 CH2Cl2 was characterized by a X-ray crystal structure determination (7873 observed independent reflexions. R = 0.048). It crystallizes in the space group P1̄ with one formula unit in the unit cell; the lattice constants are a = 1186.4; b = 1404.0; c = 1451.0 pm; α = 61.98°; β = 78.91°; γ = 78.26°. The structure consists of PPh4⊕ ions. CH2Cl2 molecules and centrosymmetric anions [Mo2(O2C-Ph)4Cl4]2⊝ containinga molybdenum d3 d3 unit with a relatively long Mo=Mo bond of 249.6 pm. The Mo≡Mo group is spanned in a chelate manner by four O atoms of two benzoate groups and by two further single O atoms of two further benzoate groups. Two terminal Cl atoms on each Mo atom complete the pentagonal bipyramidal coordination spheres about the Mo atoms.
The title compound has been prepared by the reaction of N,N,N′-tris(trimethylsilyl)benzamidine with tantalum pentachloride in CH2Cl2 suspension, forming amber-coloured, moisturesensitive crystals, which were characterized by an X-ray structure determination. Space group P 21/n, Z = 2, 4895 observed independent reflexions, R = 0.059. Lattice dimensions (-65°C): a = 1165.2(6), b = 1335.4(6), c = 1629.0(7) pm, β = 93.23(4)°. The complex forms centrosymmetric molecules dimerized via chloro bridges TaCl2Ta with TaCl bond lengths of 247.2(2) and 277.1(2) pm, the longer one being in trans-position to the imido group, which can be formulated as [xxx] (bond lengths Ta=Ν = 183.5(8), C=N = 134(1) pm, bond angle TaNC = 162.7(7)°).
The title compound has been prepared by the reaction of N-trimethylsilyl-iminotriphenylphos-phorane with copper(II) chloride in boiling CCl4 /C2H5OH, and forms moisture sensitive crystals, which are green in transmittance and black in reflexion. [Me3SiNPPh3 · CuCl2 ] 2 was characterized by its IR spectrum as well as by a crystal structure determination (4197 observed, independent reflexions, R = 0.049). The lattice dimensions are at 20 °C: a = 1102.7. b = 1407.3. c = 1560.2 pm; β = 94.27°; space group P21/n with two formula units in the unit cell. The complex consists of centrosymmetric, dimeric molecules with a planar Cu2 Cl2 ring (Cu-CI bond lengths 229 and 231 pm). A terminally bonded CI atom (Cu-CI = 221 pm) and the N atom of the Me3SiNPPh3 ligand (Cu-N = 198.5 pm) complete the coordination number four of the nearly planar surroundings of the Cu atoms.
WCl4(NCl) has been prepared as a red-brown crystal powder by the reaction of tungsten hexacarbonyl with excess nitrogen trichloride in boiling CCl4. The complex is associated via chloro bridges, forming dimeric units, according to the IR spectrum. Thermal decomposition at 200 °C leads to tungsten nitride trichloride, WNCl3,. With acetonitrile, WCl4(NCl) reacts with formation of the monomeric complex [CH,CN-WCl4(NCl)], which was characterized by its IR spectrum as well as by an X-ray structure determination. Crystal data: space group P21/m, Z = 2 (1387 independent observed reflexions, R = 0.07). Lattice dimensions at 20 °C: a = 590.4(3), b = 729.0(3), c = 1124.6(4) pm, β = 100.63(2)°. The complex forms monomeric molecules, in which the tungsten atom has a distorted octahedral environment of four chlorine atoms in equatorial positions, and the acetonitrile molecule in trans-position to the group. Bond lengths WN = 172 and NCI = 161 pm; bond angle WNCl = 175.5°.