[WNCl3 · 0,5 HN3]4; Kristallstruktur und IR-Spektrum

[WNCl₃ · 0.5 HN₃]₄: Crystal Structure and I.R. Spectrum [WNCl₃ · 0.5 HN₃]₄ is formed from tungsten hexachloride and iodine azide in dichloro methane solution yielding dark red and needleshaped crystals. The crystal structure was determined by aid of X-ray diffraction data. The compound crystallises in the triclinic space group P1 with one formula unit per unit cell (R = 0.08, 2 811 independent reflexions). The four metal atoms are arranged in a square, the edges being formed by almost linear W?N? W bridge bonds of alternating length (168 and 210 pm). Two opposite tungsten atoms are coordinated by theαN atom of a HN₃ molecule and by three terminal chloro ligands. The other tungsten atoms achieve coordination number 6 by two terminal and two bridging Cl atoms, linking the tetrameric units to bands along [010]. The i.r. spectrum is reported and assigned.     

Reaktionen silylierter Phosphanimine mit Iodmonochlorid und Iodtrichlorid. Die Kristallstrukturen von [Me3SiNPMe3 · ICl], [Ph3PNCl · ICl] und [Me3PN(H)PMe3] [ICl2]2

Reactions of Silylated Phosphorane Imines with Iodine Monochloride and Iodine Trichloride. The Crystal Structures of [Me₃SiNPMe₃ · ICl], [Ph₃PNCl · ICl], and [Me₃PN(H)PMe₃][ICl₂]₂ The donor-acceptor complex [Me₃SiNPMe₃ · ICl] has been prepared from Me₃SiNPMe₃ and ICl in acetonitrile solution forming yellow-orange crystals. [Ph₃PNCl · ICl] can be prepared by the reaction of Me₃SiNPPh₃ with ICl₃ in dichloromethane solution forming pale yellow crystals. [Me₃PN(H)PMe₃][ICl₂]₂ is formed in a small amount by a slow reaction of Me₃SiNPMe₃ with ICl₃ in CCl₄ suspension in the presence of traces of moisture. All samples are characterized by IR spectroscopy and by X-ray structure analyses. [Me₃SiNPMe₃ · ICl] (1) : Space group Iba2, Z = 8, structure solution with 1 727 observed unique reflections, R = 0.051. Lattice dimensions at ?60°C: a = 1 510.7, b = 1 862.8, c = 988.9 pm. 1 has a molecular structure in which the N atom of the phosphorane imine is connected with the iodine atom of the ICl molecule in a linear arrangement N? I? Cl. Bond lengths N? I = 222.7 pm, I? Cl = 265.1 pm. [Ph₃PNCl · ICl] (2) : Space group Pna2₁, Z = 4, structure solution with 1 530 observed unique reflections, R = 0.030. Lattice dimensions at 20°C: a = 1 522.8, b = 1 408.3, c = 865.8 pm. 2 has a molecular structure in which the N atom of the N chlorophosphorane imine is connected with the iodine atom of the ICl molecule in a linear arrangement. Bond lengths N? Cl = 174.4 pm, N? I = 229.5 pm, I? Cl = 251.2 pm. [Me₃PN(H)PMe₃][ICl₂]₂ (3) : Space group P2₁/c, Z = 4, structure solution with 1 989 observed unique reflections, R = 0.029. Lattice dimensions at ?50°C: a = 1 223.1, b = 1 090.2, c = 1 482.8 pm, β = 112.21°. 3 consists of [Me₃PN(H)PMe₃]²⁺ ions and ICl₂^? anions. The PNP bond angle of the dication amounts to 134.4° with PN distances of 165.6 and 166.1 pm, approximately according to double bonds.     

Synthese und Kristallstruktur des tetrameren Nitridokomplexes [Cu(CH3CN)4]2[W4N4Cl14(CH3CN)2]

Synthesis and Crystal Structure of the Tetrameric Nitrido Complex [Cu(CH₃CN)₄]₂[W₄N₄Cl₁₄(CH₃CN)₂] . The title compound has been prepared by the reaction of CuCl with WNCl₃ in acetonitrile solution, forming red, moisture sensitive crystals. They were characterized by IR spectroscopy and by an X-ray structure determination. Space group I2/a, Z = 4, 2 027 observed unique reflections, R = 0.049. Lattice dimensions at -80°C: a = 2 527.0, b = 971.9, c = 2 137.5 pm, β = 106.01°. The compound consists of [Cu(CH₃CN)₄]⁺ ions, which are arranged to form strands, and of anions [W₄N₄Cl₁₄(CH₃CN)₂]^2?, in which the tungsten atoms were located at the vertices of a square and are linked with one another via linear W?N? W bridges. Two of the four tungsten atoms have four chlorine atoms as terminal ligands, the other two tungsten atoms have three chlorine atoms and an acetonitrile molecule as terminal ligands.     

Synthese und Kristallstruktur des Nitridokomplexes [Na-15-Krone-5]2[MoNF4]2 · 2 CH3CN

Synthesis and Crystal Structure of the Nitrido Complex [Na-15-crown-5]₂[MoNF₄]₂ · 2 CH₃CN The title compound is synthesized by the reaction of [MoCl₄(NSCl)]₂ with excess NaF in boiling acetonitrile in the presence of the crown ether 15-crown-5. [Na-15-crown-5]₂[MoNF₄]₂ · 2 CH₃CN forms yellow crystals, which were characterized by an X-ray structure determination. Space group P1 , Z = 1. Lattice dimensions at ?90°C: a = 855.5, b = 1 069.9, C = 1 143.5 pm, α = 105.71°, β = 95.29°, γ = 102.25° (4 096 independent observed reflexions, R = 0.039). Short Na…?F contacts of 234 pm with the four axial fluoro ligands of the dimeric anion [MoNF₄]₂^2? allow formulation of a triple ion. The centrosymmetric anion is dimerized by bent fluoro bridges with Mo? F distances of 198 and 245 pm. The long Mo? F distances of the MoF₂Mo ring are in transposition to the nitrido ligands, the bond lengths of which (165 pm) correspond to triple bonds.     

Kristallstruktur des Molybdändioxiddichlorid-Phosphoroxidtrichlorid-Addukts MoO2Cl2 · POCl3

Crystal Structure of the Molybdenum Dioxide Dichloride — Phosphorus Oxide Trichloride Adduct MoO₂Cl₂ · POCl₃ The crystal structure of MoO₂Cl₂ · POCl₃ was determined by X-ray methods (R = 0.046; 2497 independent reflexions). MoO₂Cl₂ · POCl₃ crystallizes monoclinic in the space group P2₁/c with Z = 8. It forms nearly linear chains in which the Mo atoms are linked together via weakly bent and asymmetric oxo bridges (Mo? O = 172 and 218 pm). The Mo atoms are surrounded in a distorted octahedral coordination by one O and two Cl atoms (Mo? Cl = 230–232 pm) as terminal ligands and by the POCl₃ molecule and the bridging O atoms as well. The POCl₃ molecule (Mo? O = 233 pm) is located in trans position to the terminal oxo ligand (Mo? O = 166 pm).     

Zur Kenntnis der Hydrate des Typs MX2 · 1 H2O mit M = Sr,Ba und X = Cl,Br, I. Kristallstrukturen des Strontiumchlorid-Monohydrats,SrCl2 · 1 H2O,und des Strontiumbromid-Monohydrats,SrBr2 · 1 H2O

On Hydrates of the Type MX₂ · 1 H₂O with M = Sr, Ba and X = Cl, Br, I. Crystal Structures of Strontium Chloride Monohydrate, SrCl₂ · 1 H₂O, and Strontium Bromide Monohydrate, SrBr₂ · 1 H₂O The structures of SrCl₂ · 1 H₂O, orthorhombic, Pnma, a = 1088.1(1), b = 416.2(1), c = 886.4(1) pm, Z = 4, d_c = 2.92 Mg m^?3, R = 0.052 for 755 reflections, and of SrBr₂ · 1 H₂O, orthorhombic, Pnma, a = 1146.4(1), b = 429,5(1), c = 922.9(1) pm, Z = 4, d_c = 3.88 Mg m^?3, R = 0.056 for 762 reflections have been determined from a Patterson synthesis and refined by Fourier and Least Squares methods. The structure consists of [SrX₂ = H₂O]_n-layers normal to [100] and Sr? H₂O? Sr? H₂O-chains parallel [010]. The Sr? O distances are 265.1(3) pm, SrCl₂ · 1 H₂O, and 265.9(4) pm, SrBr₂ · 1 H₂O. The shortest Sr? Cl and Sr? Br distances (298.9(1) and 315.3(1) pm) are within the layers. The environment of oxygen and strontium is a distorted tricapped trigonal prism. The orientation of the water molecules has been determined from vibrational spectroscopic measurements. The hydrogen atoms H₁ and H₂ form bifurcated hydrogen bonds of different strength to neighbouring halide ions. The corresponding O···X distances are 331.9(4) and 320.2(4) pm, SrCl₂ · 1 H₂O, and 340.8(4) and 333.8(4) pm, SrBr₂ · 1 H₂O. The other O? X distances are between 310.3(5) and 323.7(5) pm, SrCl₂ · 1 H₂O, and 323.5(5) and 333.2(6) pm, SrBr₂ · 1 H₂O.     

Phosphaniminato-Komplexe von Titan(IV) und Titan(III). Die Kristallstrukturen von [TiCl2(OMe)(NPPh3)]2, [TiBr2(NPPh3)]2 · 3 C7H8 sowie von [Ph3PNH2]Br · CH2Cl2

Phosphorane Iminato Complexes of Titanium(IV) and Titanium(III). The Crystal Structures of [TiCl₂(OMe)(NPPh₃)]₂, [TiBr₂(NPPh₃)]₂ · 3C₇H₈, and [Ph₃PNH₂]Br · CH₂Cl₂ TiCl₃(NPPh₃) reacts with a solution of methyllithium in diethyl ether in the presence of lithiummethylate forming yellow [TiCl₂(OMe)(NPPh₃)]₂. On reaction with benzyl magnesium bromide TiCl₃(NPPh₃) in diethyl ether is converted into green [TiBr₂(NPPh₃)]₂ under reduction and ligand exchange. [TiBr₂(NPPh₃)]₂ crystallizes from toluene with three molecules C₇H₈. [Ph₃PNH₂]Br · CH₂Cl₂ originates as a side product of this reaction. The products are characterized by their i.r. spectra and by crystal structure analyses. [TiCl₂(OMe)(NPPh₃)]₂ . Space group P1 , Z = 2, structure solution with 2909 independent reflections, R = 0.063. Lattice dimensions at 20°C: a = 1005.1, b = 1044.5, c = 1068.6 pm, α = 66.98°, β = 89.35°, γ = 80.24°. The compound forms centrosymmetric dimeric molecules with μ₂-OMe bridges and five-fold coordinated titanium atoms. The (NPPh₃^?) ligand is terminally connected with a Ti = N distance of 174.8 pm and with a TiNP bond angle of 165.3°. [TiBr₂(NPPh₃)]₂ · 3 C₇H₈ . Space group P1 , Z = 2, structure solution with 5548 independent reflections, R = 0.053. Lattice dimensions at ?70°C: a = 983.3, b = 1162.7, c = 1376.5 pm, α = 100.53°, β = 110.30°, γ = 105.24°. The compound forms centrosymmetric dimeric molecules with μ₂-NPPh₃ bridges and tetrahedral coordination at the titanium atoms. With 195.9 pm the Ti–N bonds correspond with single bonds. The Ti …? Ti distance of 260.0 pm is exceptionally short. [Ph₃PNH₂]Br · CH₂Cl₂ . Space group P1 , Z = 1, structure solution with 3091 independent reflections, R = 0.049. Lattice dimensions at 20°C: a = 909.4, b = 1004.4, c = 1158.5 pm, α = 108.09°, β = 94.67°, γ = 91.92°. The bromide ions are bonded to a one-dimensional infinite network via hydrogen bridge bonds of the cation and of the dichloromethane.     

Dichloracetylen als stabiler Komplexligand Die Kristallstruktur von PPh4[WCl5(C2Cl2)] · 0,5 CCl4

Dichloro Acetylene as Complex Ligand. Crystal Structure of PPh₄[WCl₅(C₂Cl₂)] · 0.5 CCl₄ Tungsten hexachloride and dichloro acetylenediethyletherate react in boiling CCl₄ in presence of C₂Cl₄ as reducing agent forming [Et₂O · WCl₄(C₂Cl₂)]. In vacuo the complex looses ether giving the dichloro acetylene complex [WCl₄(C₂Cl₂)]₂ which is dimeric with chloro bridges. Both complexes react with tetraphenylphosphonium chloride to form PPh₄[WCl₅(C₂Cl₂)] which is equally prepared by ligand exchange of PPh₄[WCl₅(C₂I₂)] with silver chloride. All dichloro acetylene complexes are red to brown crystalline solids sensitive to moisture, and are thermally and mechanically very stable compared with the highly explosive dichloro acetylene. The compounds are characterized by their i.r. spectra; [Et₂O · WCl₄(C₂Cl₂)] was additionally investigated by ¹³C-nmr spectroscopy. PPh₄[WCl₅(C₂Cl₂)] · 0.5 CCl₄ formes dark brown crystals; according to the structural investigation by X-ray diffraction methods the compound crystallizes orthorhombic in the space group Pbca with 8 formula units per unit cell (1317 observed, independent reflexions, R = 0.049). The cell dimensions are a = 1702 pm, b = 1675 pm and c = 2228 pm. The compound consists of [WCl₅(C₂Cl₂)]? anions and PPh₄⊕ cations including CCl₄ molecules without bonding interactions. The tungsten atoms are seven-coordinated by five chlorine atoms and two carbon atoms. The dichloro acetylene ligand is bonded symmetrically side-on and has a C? C bond length of 128 pm. The W? C distances are 201 pm, the four equatorial Cl atoms have W? Cl bond lengths of 234 pm whereas the chlorine atom in trans-position to the W? C₂ group is situated in a distance of 244 pm.     

Zur Reaktion von Makrozyklen mit Lanthanoiden. II. Die Strukturen von [K(thf)3]2[(C22H28N4)2Sm2] · 4THF und [(C22H22N4)Co] · DME

On the Reaction of Macrocycles with Lanthanoids. II. The Crystal Structures of [K(thf)₃]₂[(C₂₂H₂₈N₄)₂Sm₂] · 4 THF and [(C₂₂H₂₂N₄)Co] · DME In a complicated redox reaction [(TMTAA)K₂] and [SmI₂(thf)₂] form the polynuclear metal complex [K(thf)₃]₂[(TMTAT)₂Sm₂]. This complex crystallizes with four molecules THF per formula unit and its structure was determined by single crystal X-ray investigation (spacegroup P2₁/c (No. 14), z = 4, a = 998.0(2) pm, = b = 2618.3(6) pm, c = 1619.4(3) pm, β = 96.52(2)°). In the dimeric unit [(TMTAT)₂Sm₂]^2? the Sm³⁺ ions are bonded to the four N atoms of the macrocyclic ligand and one C₆H₄ ring of the second ligand is attached η⁶ like to one metal ion. Additionally two [K(thf)₃]⁺ fragments are bonded to this central unit, and therefor coordination number seven results for the K⁺ ion. [TMTAA]^2? is not reduced by [Cp₂Co] in a similar reaction. The monomeric paramagnetic complex [(TMTAA)Co] (μ_eff = 2,76 μ_B) is formed instead. The structure reveils a square planar coordination of the Co atom by the four N atoms of the TMTAA ligand (spacegroup C2/c (No. 15), z = 4, a = 1945.1(4) pm, b = 1165.6(2) pm, c = 1144.7(2) pm, β = 116.38(1)°).     

Phosphaniminato-Komplexe des Schwefels. Synthese und Kristallstrukturen von [O3SS(NPPh3)2] · CH3CN, [SO(NPPh3)2] und [SCl(NPMe3)2]Cl

Phosphorane Iminato Complexes of Sulfur. Syntheses and Crystal Structures of [O₃SS(NPPh₃)₂] · CH₃CN, [SO(NPPh₃)₂], and [SCl(NPMe₃)₂]Cl The title compounds have been prepared by the reaction of Me₃SiNPPh₃ with SO₂ and SOCl₂, respectively, and by the reaction of Me₃SiNPMe₃ with S₂Cl₂. They form colourless, moisture sensitive crystals, which were characterized by IR spectroscopy and by crystal structure determinations. [O₃SS((NPPh₃)₂)] · CH₃CN : Space group Pca2₁, Z = 4, structure solution with 4016 observed unique reflections, R = 0.050. Lattice dimensions at ?60°C: a = 1865.1, b = 1168.4, c = 1569.0 pm. The compound has a zwitterionic structure with a S? S bond length of 218.2 pm and bond lengths S? N of 161.2 and P? N of 160.1 pm. [SO(NPPh₃)₂] : Space group P2₁/c, Z = 4, structure solution with 2854 observed unique reflections, R = 0.113. Lattice dimensions at ?50°C: a = 1173.1, b = 1585.6, c = 1619.2 pm, b? = 98.13°. The compound forms monomeric molecules, in which the positions of S and N atoms are disordered in two positions. The bond lengths are S? N 166 pm and P? N 163 pm in average. [SCl(NPMe₃)₂]Cl : Space group P1 , Z = 2, structure solution with 2416 observed unique reflections, R = 0.038. Lattice dimensions at 20°C: a = 613.2, b = 1030.3, c = 1111.4 pm, α = 88.48°, b? = 88.01°, γ = 83.10°. The compound forms ions [SCl(NPMe₃)₂]⁺ and Cl^?. In the cation the sulfur atom is ?-tetrahedrally coordinated with a long S? Cl distance of 246.9 pm and bond lengths S? N of 155.3 pm and P? N of 164.3 pm in average.     

CPh3⊕[Ph3CNWCl4(μ-F)WNCl2(μ-F)Cl4WNCPh3]⊖; Synthese und Kristallstruktur eines dreikernigen Nitrido-Nitren-Komplexes des Wolframs

CPh₃^⊕[Ph₃CNWCl₄(μ-F)WNCl₂(μ-F)Cl₄WNCPh₃]^?; Synthesis and Crystal Structure of a Trinuclear Nitrido Nitrene Complex of Tungsten Dark red crystals of the title compound are formed in the reaction of triphenyl carbonium tetrafluoro borate with AsPh₄[WNCl₄] in dichloro methane. They are characterized by a structural analysis by the aid of X-ray diffractional data as well as by it's IR spectrum. The complex crystallizes in the space group P_mmm with two formula units per unit cell. The cell dimensions are a = 2307, b = 1330 and c = 968 pm. Intensity measurements were carried out with 2 255 reflexions. Because of a disorder of the phenyl groups the structural parameters could only be refined to a final R-value of 9.3%. The structure consists of triphenyl carbonium cations and trinuclear anions [WNF₂Cl₂(Cl₄WNCPh₃)₂]^?. The anion can be regarded as a distorded trigonal-bipyramidal ion [WNF₂Cl₂]^?, coordinating to two molecules of Cl₄W?N? CPh₃ in trans-position to the nitrene ligands via W? F…?W bonds with different bond lengths.     

Phosphaniminato‐Komplexe des Hafniums. Die Kristallstrukturen von [Hf(NPPh3)4] · 3 THF und [Hf(NPPh3)2Cl2(HNPPh3)2]

Phosphoraneiminato Complexes of Hafnium. Crystal Structures of [Hf(NPPh₃)₄] · 3 THF and [Hf(NPPh₃)₂Cl₂(HNPPh₃)₂] The phosphoraneiminato complexes [Hf(NPPh₃)₄] · 3 THF ( 1 · 3 THF) and [Hf(NPPh₃)₂Cl₂(HNPPh₃)₂] ( 2 ) have been prepared as colourless, moisture sensitive single crystals by reactions of hafnium tetrachloride with [CsNPPh₃]₄ · 2 toluene in tetrahydrofurane solutions by application of different ratios of the educts. Both complexes are characterized by IR spectroscopy and X‐ray crystal structure determinations. 1 · 3 THF: space group P 1, Z = 4, lattice dimensions at 193 K: a = 2007.6(1); b = 2064.2(1); c = 2115.9(1) pm; α = 109.193(4)°; β = 111.285(4)°; γ = 96.879(4)°; R₁ = 0.0506. 1 forms monomeric molecules with tetrahedral coordination of the nitrogen‐atoms of the (NPPh₃^–)‐groups towards the Hafnium atom. The HfN distances of 200.9 pm in average correspond with double bonds. 2 : space group P 1, Z = 4, lattice dimensions at 193 K: a = 1444.0(1); b = 1928.1(1); c = 2455.8(2) pm; α = 67.273(8)°; β = 87.445(8)°; γ = 87.082(8)°; R₁ = 0.0312. 2 has a monomeric molecular structure with octahedral coordination of the hafnium atom. The chlorine atoms are in trans position to one another, whereas the nitrogen atoms of the phosphoraneiminato groups (NPPh₃^–) are in trans position towards the nitrogen atoms ot the phosphorane imine molecules (HNPPh₃). The HfN bond lengths of the (NPPh₃^–) groups of 199.7 pm in average correspond with double bonds, whereas the HfN distances of the HNPPh₃ molecules with bond lengths of 230.2 pm in average are of donor‐acceptor type.     

Die Bildung von PPh4[WOCl4 · THF] und PPh4Cl · 4As4S3 aus W(CO)6 und PPh4[As2SCl5] sowie ihre Kristallstrukturen

Formation of PPh₄[WOCl₄ · THF] and PPh₄Cl · 4As₄S₃ from W(CO)₆ and PPh₄[As₂SCl₅] and their Crystal Structures When W(CO)₆ and PPh₄[As₂SCl₅] are irradiated with UV light in tetrahydrofurane, PPh₄[WOCl₄ · THF], PPh₄ Cl· 4As₄S₃ and PPh₄[Cl₂H] are obtained. X-ray crystal structure determinations were performed. PPh₄[WOCl₄ · THF], monoclinic, space group P2₁/c, Z = 4, a = 1207.5(2), b = 1003.7(2), c = 2642.0(5) pm, β = 114.71(1)°, R = 0.049% for 2824 reflexions; PPh₄⁺ and [WOCl₄. THF]^? ions are present, the WOCl₄ group having the shape of a tetragonal Pyramid with a short W ? O bond (169 pm) and the THF molecule being weakly associated (W? O 236 pm). PPh₄Cl · 4AsS₃, tetragonal, I4₁/a, Z = 4, a = 1742.3(3), c = 1664.5(4) pm, R = 0.066% for 1350 reflexions; it consists of separate PPh₄⁺ and Cl^? ions and As₄S₃ molecules.     

Addukte schwefelhaltiger Heteroaromaten mit SbCl3 Untersuchungen zur Bildung und Kristallstruktur von 2,2′-Dithienyl · 2 SbCl3 und Benzo[b]thiophen · 2 SbCl3

Adducts of Sulfur-containing Hetero Aromates with SbCl₃: Studies on Formation and Crystal Structure of 2,2′-Dithienyl · 2 SbCl₃ and Benzo[b]thiophene · 2 SbCl₃ Whereas the system 2,2′-dithienyl—SbCl₃ because of irreversible thermal decomposition reactions could not be studied by DTA, this method applied to the system benzo[b]thiophene—SbCl₃ yielded a quasibinary behaviour and the existence of a compound benzo[b]thiophene · 2SbCl_3. melting congruently at 71.2°C. Crystals of this adduct and that of analogue composition 2,2′-dithienyl · 2SbCl₃ were obtained from solution. Their structures were determined by X-ray diffraction as those of bπ-v complexes. They are compared with other Menshutkin complexes. The π…?Sb interactions are indicated by distances between the planes of the planar hetero aromates and the Sb atoms located in a transoid way above both single rings of 316 (dithienyl adduct) and 325 pm (benzothiophene adduct). There is no particular coordinative bond formation by the S atoms. The intermolecular linking in the SbCl₃ partial structures is described.     

AsPh4[W2Cl4(N3S2)3] · CCl4; Synthese und Kristallstruktur

AsPh₄[W₂Cl₄(N₃S₂)₃] · CCl₄; Synthesis and Crystal Structure The title compound was obtained in form of black crystals along with other products by the reaction of H₂S and AsPh₄[WCl₄(N₃S₂)] in dichloromethane and subsequent addition of CCl₄. Its crystal structure was determined by X-ray diffraction (3036 observed reflexions, R = 0.051). Crystal data: triclinic, space group P¯1, Z = 2, a = 1369, b = 1398, c = 1441 pm, α = 64.8, β = 68.02 and γ = 58.1°. The compound consists of AsPh₄^⊕ ions, CCl₄ molecules and [W₂Cl₄(N₃S₂)₃]^? ions. In the latter, one tungsten atom is member of one planar WN₃S₂ ring while the second tungsten atom belongs to two such rings forming a nearly planar S₂N₃WN₃S₂ unit. Two nitrogen atoms of this unit are linked to the other tungsten atom forming a WN₂W ring. Two chloro ligands at each tungsten atom complete the coordination sphere to coordination numbers of six.     

Metallderivate von Molekülverbindungen. III. Molekül- und Kristallstruktur des Lithium-bis (trimethylsilyl)-phosphids · DME und des Lithium-dihydrogenphosphids · DME

Metal Derivatives of Molecular Compounds. III. Molecular and Crystal Structure of Lithium bis(trimethylsilyl)phosphide · DME and of Lithium dihydrogenphosphide · DME Lithium bis(trimethylsilyl)phosphide · DME 1 prepared from tris(trimethylsilyl)-phosphine and lithium methanide [2, 4] in 1,2-dimethoxyethane

1 1,2-Dimethoxyethan (DME); Tetrahydrofuran (THF); Bis[2-(dimethylamino)ethyl]methyl-amin (PMDETA).

, crystallizes in the orthorhombic space group Pnnn {a = 881.1(9); b = 1308.5(9); c = 1563.4(9) pm at ?120 ± 3°C; Z = 4 formula units}, lithium dihydrogenphosphide · DME 2 [10] prepared from phosphine and lithium- n -butanide in the same solvent, in P2 ₁ 2 ₁ 2 ₁ {a = 671.8(1); b = 878.6(1); c = 1332.2(2) pm at ?120 ± 3°C; Z = 4 formula units}. X-ray structure determinations (R _w = 0.036/0.045) show the bis(trimethylsilyl) derivative 1 to be dimeric with a planar P? Li? P? Li ring (P? Li 256 pm; Li? P? Li 76°; P? Li? P 104°), and the dihydrogenphosphide 2 to be polymeric with a linear Li? P? Li fragment (P? Li 254 to 260 pm; Li? P? Li 177°; P? Li? P 118°). The shortened P? Si distance (221 pm) of compound 1 and the structure of the PH ₂ group in 2 are discussed in detail. Lithium obtains its preferred coordination number 4 by a chelation with one molecule of 1,2-dimethoxyethane (Li? O 202 to 204 pm).     

Mo2O3Cl4(Pyridin)4 · CH2Cl2 Synthese,IR-Spektrum und Kristallstruktur

Mo₂O₃Cl₄(Pyridine)₄ · CH₂Cl₂. Synthesis, IR Spectrum, and Crystal Structure Reduction of MoO₂Cl₂(pyridine)₂ with triphenylphosphane in toluene and recrystallisation from CH₂Cl₂ yields brown crystal needles of the complex Mo₂O₃Cl₄(pyridine)₄ · CH₂Cl₂. The compound crystallizes monoclinic in the space group P2₁/c with four formula units per unit cell of the dimensions a = 1 234.6 pm; b = 1 593 pm, c = 1 522.3 pm and β = 105.66° A structural investigation by X-ray methods (3 276 independent observed reflexions, R = 0.033) reveals the molecule with two molybdenum atoms in a distorted octahedral coordination linked by an almost linear Mo? O? Mo bridge with bond distances of 167 and 168 pm, respectively. The chlorine atoms are located in trans-position to the oxygen atoms which have different trans effects: The Mo? Cl bond opposite the bridge (length 242 pm) is 8 pm shorter than the bond in trans position to the terminal oxo ligands. The pyridine nitrogen atoms are in trans position to each other and complete the coordination of the molybdenum atoms. The i.r. spectrum of the compound is reported.     

Synthese und Molekülstruktur von Barium-bis[N,N′-bis(trimethylsilyl)benzamidinat] · DME · THF

Synthesis and Molecular Structure of Barium Bis[N,N′-bis(trimethylsilyl)benzamidinate] ° DME ° THF Barium bis[N,N′-bis(trimethylsilyl)benzamidinate] · thf · dme crystallizes in the monoclinic space group P2₁/n with a = 1 122.0(2), b = 2 190.7(4), c = 1 840.2(3) pm, β = 98.04(1)° and Z = 4 containing a metal center in a distorted monocapped trigonal prismatic surrounding. The barium dibenzamidinate moiety is sent with an angle of 120°, although this leads to different Ba? N distances of 273 and 282 pm originating from the interligand repulsion of the trimethylsilyl groups and the dme substituent. The 1,3-diazaallyl fragment with C? N bond lengths of 132 pm shows a delocalisation of the anionic charge.     

Zur Darstellung und Kristallstruktur von CrSO4 · 3 H2O

Preparation and Crystal Structure of CrSO₄ · 3 H₂O Evaporating a solution of Cr²⁺ in dilute sulphuric acid at 70°C light blue crystals of CrSO₄ · 3 H₂O were grown. Its x-ray powder diffraction pattern is quite similar to that of CuSO₄ · 3 H₂O. The crystal structure refinement of CrSO₄ · 3 H₂O (space group Ce, a = 5.7056(8) Å, b = 13.211(2) Å, c = 7.485(1) Å, β = 96.73(1)°, Z = 4) from single crystal data, using the parameters of the copper compound as starting values, results in a final R-value of R = 3.8%. The surrounding of the Cr²⁺ ion can be described as a strongly elongated octahedron. The basal plane of the CrO₆-octahedron consists of three hydrate oxygen atoms and one sulphate oxygen atom. The two more distant axial oxygen atoms also belong to sulphate groups. Thus they are forming chains of alterning CrO₆-octahedra and SO₄-tetrahedra along [110] and [1–10] linked via common corners. These chains are connected via sulphate groups and by bridging hydrogen bonds to a 3-dimensional network.     

Synthesis,Spectroscopy and Crystal Structures of Chiral Organic Ammonium Tetrathiometalates Showing N‐H···S and C‐H···S Interactions

The reaction of ammonium tetrathiometalate (NH₄)₂[MS₄] (M = W or Mo) with the R(+) or S(?) forms of the organic amine α‐methylbenzylamine [PhCH(CH₃)NH₂] results in the formation of the corresponding non‐centrosymmetric bis(α‐methylbenzylammonium) tetrathiometalate complexes [PhCH(CH₃)NH₃]₂[MS₄] (R‐ammonium M = W 1 ; R‐ammonium M = Mo 2 ; S‐ammonium M = W 3 , S‐ammonium M = Mo 4 ) which were characterized by elemental analysis, IR, Raman, UV‐Vis and CD spectra, X‐ray powder diffractometry and single crystal X‐ray crystallography. Compounds 1 ‐ 4 crystallize in the chiral space group P2₁ and constitute the first examples of structurally characterized chiral organic ammonium group VI tetrathiometalates. The structures of 1 ‐ 4 consist of two crystallographically independent chiral organic ammonium cations and a tetrahedral tetrathiometalate dianion. The N‐H···S and C‐H···S interactions between the anions and cations organise them such that the organic ammonium ions always point towards the S atoms of [MS₄]^2?.