Synthese und Struktur von Mo2NCl7

Synthesis and Structure of Mo₂NCl₇ The reaction of VN with MoCl₅ at 175 °C in a sealed glass ampoule yields the molybdenum(V) nitride chloride Mo₂NCl₇ in form of air sensitive black crystals with the triclinic space group P1¯ and a = 905.7(8); b = 975.4((6); c = 1283.4(8) pm, α = 103.13(4)°; β = 109.83(5)° und γ = 98.58(5)°. The crystal structure is built up from dinuclear units [Mo₂N₂Cl₇]^3— and [Mo₂Cl₇]³⁺, which are connected by asymmetric nitrido bridges to form endless chains. Within both dinuclear units the Mo atoms are bridged by three Cl atoms resulting in a Mo‐Mo distance of 349.2(3) pm in the unit [Mo₂N₂Cl₇]^3—. In case of [Mo₂Cl₇]³⁺, however, a shorter Mo‐Mo distance of 289.4(3) pm is observed, which can be interpreted by a single bond. Correspondingly a reduced magnetic moment of 0.95 B.M. per Mo atom is observed.     

Reactions of the Complexes ReNCl2(PMe2Ph)3, [ReNCl4]—, [OsO3N]—, and Cl3VNCl with Metal Halides

The nitrido complexes ReNCl₂(PMe₂Ph)₃ and [OsO₃N]^— have strong basic terminal nitrido ligands which can react with Lewis acidic metal halides to form nitrido bridges. The synthesis and structure of complexes with ReNCl₂(PMe₂Ph)₃ and nitrido bridges Re≡N‐M (M = B, Ga, Sn, Ti, Zr, V, Nb, Ta, Mo, Re, Pd, Au, and Zn) as well as of complexes with [OsO₃N]^— and nitrido bridges Os≡N‐M (M = Pd and Pt) are reported. Strong Lewis acids can also remove phosphine or chloro ligands from ReNCl₂(PMe₂Ph)₃. The resulting complex fragments subsequently combine to yield oligomeric complexes with nitrido bridges Re≡N‐Re. If the reaction with strong Lewis acids is carried out in a chlorinated solvent the solvent can be decomposed to form HCl which then protonates the nitrido ligand affording an imido complex. [ReNCl₄]^— is able to form nitrido bridges to electrophilic halides if a donor ligand is coordinated in trans position to the nitrido ligand to enhance its basicity sufficiently. The synthesis and structure of examples with nitrido bridges Re≡N‐M (M = Pd, Pt, Ta) are reported. The chloro imido complex Cl₃V≡N‐Cl can act as a nitride ion transfer reagent. Its reaction with MoCl₅ yields Mo₂NCl₈ whereas with MoCl₃ the nitride chlorides Mo₃N₂Cl₁₁ and MoNCl₃ are obtained. Cl₃VNCl can also act as an reactive intermediate by the reaction of VN with a halide as was shown by the reaction of MoCl₅ with VN yielding Mo₂NCl₇. The structures of these molybdenum nitride chlorides are discussed.     

Synthese und Kristallstruktur der Molybdännitrido‐Komplexe [MoNCl3(MeCN)]4 und [MoNCl2(bipy)]4

Syntheses and Crystal Structures of the Nitrido Complexes [MoNCl₃(MeCN)]₄ and [MoNCl₂(bipy)]₄ [MoNCl₃(MeCN)]₄ ( 1 ) is obtained by the reaction of MoCl₄(MeCN)₂ with Me₃SiN₃ in CH₂Cl₂ as a sparingly soluble and water sensitive red compound. It crystallizes as 1 · 3 CH₂Cl₂ in the triclinic space group P 1 with a = 889.7(1), b = 1004.8(1), c = 1270.4(2) pm; α = 71.69(1)°; β = 73.63(1)°; γ = 86.32(1)°, and Z = 1. It forms centrosymmetric tetranuclear complexes, in which the Mo atoms are connected by asymmetric and linear nitrido bridges with distances Mo–N of 167.5 and 214.3 pm. The acetonitrile molecules are coordinated with a long bond length Mo–N of 241 pm in trans position to the Mo–N triple bond. The reaction of 1 with 2,2′‐bipyridine in CH₂Cl₂/THF yields the tetranuclear molybdenum(V) complex [MoNCl₂(bipy)]₄ ( 2 ) as main product. It crystallizes in the tetragonal space group P4₂/n with a = 1637.5(2), c = 1018.3(2) pm, and Z = 2. In the tetranuclear complexes with the symmetry S₄ linear and asymmetric nitrido bridges connect the Mo atoms to form an almost planar eight membered Mo–N ring with distances Mo–N of 173 and 203 pm. The bipyridine molecules coordinate as chelates in cis and trans position to the Mo–N triple bond. In this case the trans influence causes different Mo–N distances of 219 and 232 pm.     

Synthese und Kristallstruktur von (PPh4)2[Mo2NCl9]2, einem μ-Nitridokomplex mit Molybdän(V), und -(VI)

Synthesis and Crystal Structure of (PPh₄)₂[Mo₂NCl₉]₂, a μ-Nitrido Complex with Molybdenum (V) and (VI) The title compound is formed as a by-product in the partial oxidation of Mo₂NCl₇ with chlorine in POCl₃ solution, when the reaction mixture is treated with PPh₄Cl. The crystals, which are sensitive to moisture, are black in reflectance and red in transmittance. A more effective synthesis is the direct reaction of PPh₄[MoNCl₄] with MoCl₅ in dichloro methane. (PPh₄)₂[Mo₂NCl₉]₂ was characterized by the i.r. spectrum and by a structural analysis with X-ray data. The compound crystallizes triclinic in the space group P1 with two formula units per unit cell (9225 independent observed reflexions, R = 0.058). The cell parameters are (20°C): a = 1144 pm, b = 1517 pm, c = 2000 pm, α = 79.8°, β = 80.1°, γ = 72.1°. (PPh₄)₂[Mo₂NCl₉]₂ consists of PPh₄⊕ cations and the anions [Mo₂NCl₉]₂^22?, which dimerize via chloro bridges with Mo? Cl bons lengths of 243 pm and 287 pm. In the [Mo₂NCl₉]₂^2? units the molybdenum atoms are linked by Mo^VI?N? Mo^V bridges (bond angles 179° and 174°, resp.) with Mo? N bond lengths of 167 pm and 212 pm.     

Synthese und Struktur von zwei- und dreikernigen Heterometallkomplexen mit Nitridobrücken zwischen Re und Mo

Synthesis and Structure of Two- and Threenuclear Heterometallic Complexes with Nitrido Bridges between Re and Mo The reaction of ReNCl₂(PMe₂Ph)₃ with MoCl₄(NCEt)₂ yields the heterometallic threenuclear complex [{(Me₂PhP)₃(EtCN)ClRe≡N–}₂MoCl₄][MoNCl₅]. The anion [MoNCl₅]^2– presumably results from a transfer of the nitrido ligand from the Re to the Mo atom. The air-sensitive compound is paramagnetic with μ_eff = 2.87 B. M. at room temperature. A reduction of the magnetic moment to 1.74 B.M at 20 K starts at 140 K. The complex crystallizes in the orthorhombic space group Pca2₁ with a = 2430(1), b = 1328(1), c = 2436.3(2) pm, Z = 4. With bond angles Re–N–Mo of 164° and 167° the nitrido bridges are almost linear. The distances Re–N of 169 and 170 pm can be interpreted with triple bonds. The Mo–N bond lengths of 210 and 211 pm correspond to single bonds. In the anion [MoNCl₅]^2– the distance Mo≡N is 167 pm. Hydrolysis of the threenuclear complex results in a cleavage of one of the nitrido bridges to yield (Me₂PhP)₃(EtCN)ClRe≡N–MoOCl₄. The compound is paramagnetic with μ_eff = 1.71 B.M. at room temperature. It crystallizes in the orthorhombic space group Pbca with a = 1718.5(4), b = 2037(1), c = 2041.1(7) pm, Z = 8. In the dinuclear complex the [MoOCl₄]^– unit is only weakly coordinated to the nitrido ligand with Mo–N = 246.5 pm, while the distance of the Re≡N bond of 168.1 pm is almost unchanged in comparison with a terminal bond. The bond angle Re≡N–Mo is 165.6°.     

[MoNCl3(THF)]4 – ein Nitrido-Komplex mit gefaltetem Mo4N4-Achtring

[MoNCl₃(THF)]₄ – a Nitrido Complex with a Folded Mo₄N₄ Eight-Membered Ring Red moisture sensitive single crystals of [MoNCl₃(THF)]₄ ( 1 ) prepared from saturated solutions of CH₂Cl₂ were characterized by a crystal structure determination. Space group P 4 2₁c, Z = 2, lattice dimensions at –80 °C: a = b = 1291.2(1), c = 1116.3(1) pm, R = 0.0581. In 1 the molybdenum atoms are linked by nearly linear Mo≡N–Mo bridges with MoN distances of 167 and 216 pm, which corresponds with triple and single bonds. In trans position to the Mo≡N bond the THF molecule is bonded by its oxygen atom. Along the diagonal axis Mo…Mo 1 is folded with an aperture angle of 140° thus forming a butterfly structure.     

Synthese und Struktur von (PPh4)3[Re2NCl10]

Synthesis and Crystal Structure of (PPh₄)₃[Re₂NCl₁₀] The rhenium(V) nitrido complex (PPh₄)₃[Re₂NCl₁₀] ( 1 ) is obtained from the reaction of (PPh₄)[ReNCl₄] with 1, 3‐dioxan‐(2‐ylmethyl)diphenyl phosphine in CH₂Cl₂/CH₃CN in form of orange red crystals with the composition 1 ·2CH₂Cl₂ crystallizing in the triclinic space group P1¯ with a = 1210.7(2), b = 1232.5(1), c = 2756.3(5) pm, α = 99.68(1)°, β = 100.24(1)°, γ = 98.59(1)° and Z = 2. The crystal structure contains two symmetry independent, centrosymmetrical complex anions [Re₂NCl₁₀]^3‐ with a symmetrical nitrido bridge Re=N=Re and distances Re(1) ‐ N(1) = 181.34(5) and Re(2) ‐ N(2) = 181.51(4) pm.     

Über Thallium(I)-chlorooxomolybdate: Synthese und Kristallstrukturen von Tl[MoOCl4(NCCH3)], Tl[Mo2O2Cl7] und Tl2[Mo4O4Cl14] und die Struktur von Tl2[MoCl6]

On Thallium(I)-oxochloromolybdates: Synthesis and Crystal Structures of Tl[MoOCl₄(NCCH₃)], Tl[Mo₂O₂Cl₇], and Tl₂[Mo₄O₄Cl₁₄] and the Structure of Tl₂[MoCl₆] Black crystals of Tl₂[MoCl₆] are formed in the reaction of TlCl with MoOCl₃ in a sealed evacuated glass ampoule at 350 °C. The crystal structure analysis shows that Tl₂[MoCl₆] (cubic, Fm 3¯m, a = 986.35(7) pm) adopts the K₂[PtCl₆] structure with a Mo–Cl bond length of 236.6 pm. Tl[MoOCl₄(NCCH₃)] was obtained by the reaction of TlCl with MoOCl₃ in acetonitrile in form of yellow, moisture sensitive crystals. The structure (orthorhombic, Cmcm, a = 746.0(1), b = 1463.8(3), c = 857.3(2) pm) is built of Tl⁺ cations and octahedral [MoOCl₄(NCCH₃)]^– anions in which the acetonitrile ligand is bound in trans position to the oxygen. The reaction of TlCl and MoOCl₃ in dichloromethane yields Tl[Mo₂O₂Cl₇] and Tl₂[Mo₄O₄Cl₁₄] as green moisture sensitive crystals. The structure of Tl[Mo₂O₂Cl₇] (orthorhombic, Pmmn, a = 694.3(1), b = 951.9(2), c = 904.7(1) pm) consists of Tl⁺ cations and dinuclear [Mo₂O₂Cl₇]^– anions, with two equidistant chlorine bridges of 248.2 and one longer chlorine bridge of 265.7 pm. The oxygen atoms are located in the trans positions of the longer chloro bridge. The structure of Tl₂[Mo₄O₄Cl₁₄] (triclinic, P1¯, a = 692.8(1), b = 919.6(1), c = 998.9(1) pm, α = 104.94(1)°, β = 90.31(1)°, γ = 108.14(1)°) is build of Tl⁺ cations and [Mo₄O₄Cl₁₄]^2– anions which form tetramers of distorted octahedral, edgesharing (MoOCl₅) units with chlorine atoms in the bridging positions. The oxygen atoms are located in the trans positions of the longest chlorine bridges.     

Synthese und Struktur der Nitrido‐Komplexe [(n‐Bu)4N]2[{(L)Cl4Re≡N}2PtCl2] (L = THF und H2O) und [(n‐Bu)4N]2[(H2O)Cl4Re≡N‐PtCl(μ‐Cl)]2

Synthesis and Crystal Structure of the Nitrido Complexes [(n‐Bu)₄N]₂[{(L)Cl₄Re≡N}₂PtCl₂] (L = THF und H₂O) and [(n‐Bu)₄N]₂[(H₂O)Cl₄Re≡N‐PtCl(μ‐Cl)]₂ The threenuclear complex [(n‐Bu)₄N]₂[{(THF)Cl₄Re≡N}_2—PtCl₂] ( 1a ) is obtained by the reaction of [(n‐Bu)₄N][ReNCl₄] with [PtCl₂(C₆H₅CN)₂] in THF/CH₂Cl₂. It forms red crystals with the composition 1a · 2 CH₂Cl₂ crystallizing in the tetragonal space group I4₁/a with a = 3186.7(2); c = 1311.2(1) pm and Z = 8. If the reaction of the educts is carried out without THF, however under exposure to air the compound [(n‐Bu)₄N]₂[{(H₂O)Cl₄Re≡N}₂PtCl₂] ( 1b ) is obtained as red trigonal crystals with the space group R3 and a = 3628.3(3), c = 1231.4(1) pm and Z = 9. In the centrosymmetric complex anions [{(L)Cl₄Re≡N}₂PtCl₂]^2— a linear PtCl₂moiety is connected in a trans arrangement with two complex fragments [(L)Cl₄Re≡N]^— via asymmetric nitrido bridges Re≡dqN‐Pt. For Pt^II such results a square‐planar coordination PtCl₂N₂. The linear nitrido bridges are characterized by distances Re‐N = 169.5 pm and Pt‐N = 188.8 pm ( 1a ), respectively, Re‐N = 165.6 pm and Pt‐N = 194.1 pm ( 1b ). By the reaction of [(n‐Bu)₄N][ReNCl₄] with PtCl₄ in CH₂Cl₂ platinum is reduced forming the heterometallic Re^VI/Pt^II complex, [(n‐Bu)₄N]₂[(H₂O)Cl₄Re≡N‐PtCl(μ‐Cl)]₂ ( 2 ). It crystallizes in the monoclinic space group C2/c with a = 2012.9(1); b = 1109.0(2); c = 2687.4(4) pm; β = 111.65(1)° and Z = 4. In the central unit ClPt(μ‐Cl)₂PtCl of the anionic complex [(H₂O)Cl₄Re≡N‐PtCl(μ‐Cl)]₂^2— with the symmetry C₂ the coordination of the Pt atoms is completed by two nitrido bridges Re≡N‐Pt to nitrido complex fragments [(H₂O)Cl₄Re≡N] ^— forming a square‐planar arrangement for the Pt atoms. The distances in the linear nitrido bridges are Re‐N = 165.9 pm and Pt‐N = 190.1 pm.     

Synthese und Struktur von [(Me2PhP)3Cl2ReN]2NbCl4 und [Re3N3Cl5(PMe2Ph)6][NbCl6]

Synthesis and Structure of [(Me₂PhP)₃Cl₂ReN]₂NbCl₄ and [Re₃N₃Cl₅(PMe₂Ph)₆][NbCl₆] The reaction of ReNCl₂(PMe₂Ph)₃ with NbCl₅ in toluene yields the trinuclear complexes [(Me₂PhP)₃Cl₂ReN]₂‐ NbCl₄ (1) and [Re₃N₃Cl₅(PMe₂Ph)₆][NbCl₆] ( 2 ). 1 forms triclinic crystals with the composition 1 · 2 C₇H₈ (P 1, a = 1074.5(1), b = 1289.1(2), c = 1299.3(2) pm, α = 85.25(2)°, β = 81.04(2)°, γ = 86.02(1)°, Z = 1). In the centrosymmetric compound 1 two complexes ReNCl₂(PMe₂Ph)₃ coordinate with their nitrido ligands a square planar, central unit NbCl₄ to form an almost linear arrangement Re≡N–Nb–N≡Re. The length of the Re–N triple bonds is 172,2 pm, and the Nb–N distances of 216.0 pm correspond to coordinative single bonds. 2 forms orthorhombic crystals with the space group P2₁2₁2₁ and a = 1286.0(1), b = 2109.2(4), c = 2436.2(3) pm, Z = 4. The three Re atoms are located at the corners of a triangle. They are connected by two asymmetric nitrido bridges and two asymmetric chloro bridges. The weakly bent nitrido bridges (Re–N–Re = 152° and 157°) are characterized by Re–N distances of 169 und 207 pm as well as 171 and 207 pm. Re1, in addition, binds a terminal nitrido ligand with Re1–N1 = 166 pm.     

(PPh4)2[MoN(N3)3Cl]2; Synthese,IR-Spektrum und Kristallstruktur

(PPh₄)₂[MoN(N₃)₃Cl]₂; Synthesis, IR Spectrum, and Crystal Structure The title compound is formed in the reaction of molybdenum (II) benzoate with trimethylsilyl azide and PPh₄Cl in dichloro methane forming dark red single crystals. A PPh₃Me⊕ salt of the ion [MoN(N₃)₃Cl]₂^2? is obtained from (PPh₃Me)₂MoNCl₄] treated with silver azide in CH₂Cl₂ suspension. The solvent CH₂Cl₂ participates in both reactions as oxidizing agent. (PPh₄)₂[MoN(N₃)₃Cl₂ is characterized by a structural analysis based upon X-ray data: space group P1 , Z = 1, a = 1050.7 pm; b = 1185.4 pm; c = 1190.8 pm; α = 98.90°; β = 106.87°; γ = 103.97° (4505 independent, observed reflexions, R = 0.039). The compound consists of PPh₄⊕ cations and centrosymmetric anions [MoN(N₃)₃Cl₂^2? in which the molybdenum atoms are bridged by the N_α atoms of two azide groups; the resulting Mo? N bond lengths are 208 pm and 260 pm. In trans position to the long Mo? N bond the terminal nitrido ligand is situated, the Mo?N distance of 164 pm corresponds to a triple bond. Two terminal azido ligands and the chloro ligand are filling up the coordination sphere of the molybdenum atoms to a coordination number of six. The i.r. spectrum is reported and assigned.     

(NH4)3[M2NCl10] (M = Nb,Ta): Synthese,Kristallstruktur und Phasenumwandlung

(NH₄)₃[M₂NCl₁₀] (M = Nb, Ta): Synthesis, Crystal Structure, and Phase Transition The nitrido complexes (NH₄)₃[Nb₂NCl₁₀], and (NH₄)₃[Ta₂NCl₁₀] are obtained in form of moisture-sensitive, tetragonal crystals by the reaction of the corresponding pentachlorides with NH₄Cl at 400 °C in sealed glass ampoules. Both compounds crystallize isotypically in two modifications, a low temperature form with the space group P4/mnc and a high temperature form with space group I4/mmm. In case of (NH₄)₃[Ta₂NCl₁₀] a continuous phase transition occurs between –70 °C and +60 °C. For the niobium compound this phase transition is not yet fully completed at 90 °C. The structure of (NH₄)₃[Nb₂NCl₁₀] was determined at several temperatures between –65 °C und +90 °C to carefully follow the continuous phase transition. For (NH₄)₃[Ta₂NCl₁₀] the structure of the low temperature form was determined at –70 °C, and of the high temperature form at +60 °C. The closely related crystal structures of the two modifications contain NH₄⁺ cations and [M₂NCl₁₀]^3– anions. The anions with the symmetry D_4h are characterized by a symmetrical nitrido bridge M=N=M with distances Nb–N = 184.5(1) pm at –65 °C or 183.8(2) pm at 90 °C, and Ta–N = 184.86(5) pm at –70 °C or 184.57(5) pm at 60 °C.     

Neue Phosphaniminato‐Komplexe von Molybdän und Wolfram. Die Kristallstrukturen von [(μ‐S2N2){MoCl4(NPPh3)}2], [Mo(NPPh3)4][BF4]2, [W(S)2(NPPh3)2] und [Ph3PNH2]+[SCN]–

New Phosphoraneiminato Complexes of Molybdenum and Tungsten. Crystal Structures of [(μ‐S₂N₂){MoCl₄(NPPh₃)}₂], [Mo(NPPh₃)₄][BF₄]₂, [W(S)₂(NPPh₃)₂], and [Ph₃PNH₂]⁺[SCN]^– The binuclear molybdenum(V)phosphoraneiminato complex [(μ‐S₂N₂){Mo^VCl₄(NPPh₃)}₂] ( 1 ) has been prepared by the reaction of the chlorothionitreno complex [Mo^VICl₄(NSCl)]₂ with Me₃SiNPPh₃ in dichloromethane forming green crystals. The temperature dependent magnetic susceptibility in the range of 2–30 K shows ideal behaviour according to the Curie law with a magnetic moment of 1.60 B.M. According to the crystal structure determination 1 forms centrosymmetric molecules in which the molybdenum atoms are connected by the nitrogen atoms of the S₂N₂ molecule. In trans‐position to it the nitrogen atoms of the phosphoraneiminato groups (NPPh₃^–) are coordinated with Mo–N bond lengths of 171(1) pm. The tetrakis(phosphoraneiminato) complex [Mo(NPPh₃)₄]‐ [BF₄]₂ ( 2 ) has been obtained as colourless crystal needles by the reaction of MoN(NPPh₃)₃ with boron trifluoride etherate in toluene solution. In the dication the molybdenum atom is tetrahedrally coordinated by the nitrogen atoms of the (NPPh₃^–) groups with Mo–N bond lengths of 179,8–181,0(3) pm. The dithio‐bis(phosphoraneiminato) tungsten complex [W(S)₂(NPPh₃)₂] ( 3 ) is formed as yellow crystals as well as [Ph₃PNH₂]⁺[SCN]^– ( 4 ) from the reaction of WN(NPPh₃)₃ with carbon disulfide in tetrahydrofurane in the presence of traces of water. 3 has a monomeric molecular structure with tetrahedrally coordinated tungsten atom with bond lengths W–S of 214.5(5) pm and W–N of 179(1) pm. In the structure of 4 the thiocyanate ions are associated by hydrogen bonds of the NH₂ group of the [Ph₃PNH₂]⁺ ion to give a zigzag chain. 1 : Space group Pbca, Z = 4, lattice constants at –80 °C: a = 1647.9(3), b = 1460.8(2), c = 1810.4(4) pm; R₁ = 0.0981. 2 : Space group P1, Z = 2, lattice constants at –80 °C: a = 1162.5(1), b = 1238.0(1), c = 2346.2(2) pm; α = 103.14(1)°, β = 90.13(1)°, γ = 97.66(1)°; R₁ = 0.0423. 3 : Space group Fdd2, Z = 8, lattice constants at –80 °C: a = 3310.1(4), b = 2059.7(2), c = 966,7(1) pm; R₁ = 0.0696. 4 : Space group P2₁2₁2₁, Z = 4, lattice constants at –80 °C: a = 1118.4(1), b = 1206.7(1), c = 1279.9(1) pm; R₁ = 0.0311.     

Synthese und Kristallstrukturen der Nitrido‐Chloro‐Molybdate [Mg(THF)4{NMoCl4(THF)}2] · 4 CH2Cl2 und [Li(12‐Krone‐4)(NMoCl4)]2 · 2 CH2Cl2

Syntheses and Crystal Structures of the Nitrido‐chloro‐molybdates [Mg(THF)₄{NMoCl₄(THF)}₂] · 4 CH₂Cl₂ and [Li(12‐Crown‐4)(NMoCl₄)]₂ · 2 CH₂Cl₂ Both the title compounds as well as [Li(12‐crown‐4)₂]⁺MoNCl₄^– were made from MoNCl₃ and the chlorides MgCl₂ and LiCl, respectively, in dichloromethane suspensions in the presence of tetrahydrofuran and 12‐crown‐4, respectively. They form orange‐red moisture‐sensitive crystals, which were characterized by their IR spectra and partly by crystal structure analyses. [Mg(THF)₄{NMoCl₄(THF)}₂] · 4 CH₂Cl₂ ( 1 ): space group C2/m, Z = 2, lattice dimensions at –50 °C: a = 1736.6(1), b = 1194.8(1), c = 1293.5(2) pm; β = 90.87(1)°; R₁ = 0.037. In 1 the magnesium ion is coordinated octahedrally by the oxygen atoms of the four THF molecules and in trans‐position by the nitrogen atoms of the two [N≡MoCl₄(THF)]^– ions. [Li(12‐crown‐4)(NMoCl₄)]₂ · 2 CH₂Cl₂ ( 2 ): space group P 1, Z = 1, lattice dimensions at –70 °C: a = 930.4(1), b = 957.9(1), c = 1264.6(1) pm; α = 68.91(1)°, β = 81.38(1)°, γ = 63.84(1)°; R₁ = 0.0643. 2 forms a centrosymmetric ion ensemble in the dimeric cation of which, i. e. [Li(12‐crown‐4)]₂²⁺, the lithium ions on the one hand are connected to the four oxygen atoms each of the crown ether molecules in a way not yet known; and in addition, each of the lithium ions enters into a intermolecular Li–O bond with neighboring crown ether molecules under formation of a Li₂O₂ four‐membered ring. The two N≡MoCl₄^– counterions are loosely coordinated to one oxygen atom each of the crown ether molecules with Mo–O distances of 320.2 pm.     

Dithiolylium‐Chlorooxomolybdate(V): Synthese und Kristallstruktur von (C3Cl3S2)[MoOCl4] und (C3Cl3S2)[Mo2O2Cl7]

Dithiolylium Chlorooxomolybdates(V): Synthesis and Crystal Structure of (C₃Cl₃S₂)[MoOCl₄] and (C₃Cl₃S₂)[Mo₂O₂Cl₇] The reaction of 3, 4, 5‐Trichlor‐1, 2‐dithiolylium chloride with MoOCl₃ in dichlormethane under solvothermal conditions at 65 °C simultaneously yields the green tetrachlorooxomolybdate(V) (C₃Cl₃S₂)[MoOCl₄] and the yellow‐brown heptachlorodioxodimolybdate(V) (C₃Cl₃S₂)[Mo₂O₂Cl₇]. The crystal structures of both compounds contain nearly planar (C₃Cl₃S₂)⁺ ions with a S—S bond length of 203 pm. The discrete [MoOCl₄]^— ion in the structure of (C₃Cl₃S₂)[MoOCl₄] has the shape of a square pyramid with the oxygen atom at the apex. The molybdenum atom is displaced by 58 pm from the basal plane towards the oxygen atom. The [Mo₂O₂Cl₇]^— ion in the structure of (C₃Cl₃S₂)[Mo₂O₂Cl₇] has the form of a face‐sharing double octahedron. It is formally composed of a [MoOCl₄]^— ion and a MoOCl₃ molecule connected by one symmetrical and two unsymmetrical chloro bridges. The molybdenum atoms placed in the centers of such connected octahedra are 357 pm apart, indicating no Mo—Mo bond.     

Das Addukt von BiCl3 mit Mo6Cl12: [BiCl]-Hanteln in der Struktur von [BiCl][Mo6Cl14]

The Adduct of BiCl₃ and Mo₆Cl₁₂: [BiCl] Dumbbells in the Structure of [BiCl][Mo₆Cl₁₄] MoCl₃ reacts under decomposition to MoCl₂ and Cl₂ with BiCl₃ in a sealed evacuated glass ampoule at 550 °C to form light red crystals of [BiCl][Mo₆Cl₁₄]. The crystal structure determination (monoclinic, C 2/c, a = 1268.1(4) pm, b = 1304.6(3) pm, c = 2571.9(8) pm, β = 91.79(3)°, Z = 8) shows that the structure is built of [(Mo₆Cl₈)Cl₆] units containing nearly regular octahedral Mo₆ clusters. These units are arranged in the motiv of a cubic closest packing. The octahedral interstices contain [BiCl] dumbbells with a Bi–Cl bond length of 249 pm. The coordination sphere of the Bi atom is completed by six weaker Bi–Cl-contacts of 275 to 308 pm length to a distorted monocapped trigonal prism. Neglecting the secondary Bi–Cl bonds, the title compound can be formulated as [(BiCl)²⁺][(Mo₆Cl₁₄)^2–].     

Synthese und Struktur der Nitrido‐Komplexe (PPh4)2[(O3Os≡N)2MCl2](M = Pd und Pt) und [{(Me2PhP)3Cl2Re≡N}2PdCl2]

Synthesis and Structure of the Nitrido Complexes (PPh₄)₂[(O₃Os≡N)₂ MCl₂] (M = Pd und Pt) and [{(Me₂PhP)₃Cl₂Re≡N}₂PdCl₂] The threenuclear complexes (PPh₄)₂[(O₃Os≡N)₂MCl₂] (M = Pd ( 1a ) and Pt ( 1b )) are obtained by the reaction of (PPh₄) [OsO₃N] with [MCl₂(NCC₆H₅)₂] (M = Pd and Pt) in form of orange red ( 1a ) or red brown ( 1b ) crystals. The compounds crystallize isotypically in the monoclinic space group P2₁/n with a = 1052.35(6), b = 1376.70(6), c = 1607.3(1) pm, β = 94.669(7)°, and Z = 2 for 1a and a = 1053.27(7), b = 1371.6(1), c = 1615.9(1) pm, β = 94.557(7)°, and Z = 2 for 1b . In the centrosymmetric complex anions [(O₃O≡N)₂MCl₂]^2— a linear MCl₂ moiety is connected in trans arrangement with two complexes [O₃Os≡N]^— via asymmetric nitrido bridges Os≡N‐M. For the M²⁺ cations such results a square‐planar coordination MCl₂N₂. The virtually linear nitrido bridges are characterized by distances Os‐N = 167.5 pm ( 1a ) and 164.2 pm ( 1b ) as well as Pd‐N = 196.2 pm and Pt‐N = 197.8 pm. The reaction of ReNCl₂(PMe₂Ph)₃ with PdCl₂(NCC₆H₅)₂ in CH₂Cl₂ yields red crystals of the heterometallic complex [{(Me₂PhP)₃Cl₂Re≡N}₂PdCl₂] ( 2 ). It crystallizes as 2 · 2 CH₂Cl₂ in the monoclinic space group C2/c with a = 2138.3(5); b = 1260.9(3); c = 2375.6(2) pm; β = 96.09(1)° and Z = 4. In the threenuclear complex [{(Me₂PhP)₃Cl₂Re≡N}₂PdCl₂] with the symmetry C_i the coordination of the Pd²⁺ cation of the central PdCl₂ unit is completed by two nitrido bridges Re≡N‐Pd to complexes (Me₂PhP)₃Cl₂Re≡N forming a square‐planar arrangement. The distances in the linear nitrido bridges are Re‐N = 170.2 pm and Pd‐N = 197.1 pm.     

Molybdännitridtrichlorid-di-n-butylether, [MoNCl3 · O(C4H9)2]4; Darstellung,IR-Spektrum und Kristallstruktur

Molybdenum-nitride-trichloride-di-n -butylether [MoNCls₃ · 0 (C₄H₉)₂]₄; Preparation, I.R. Spectrum, and Crystal Structure Phenyldiazonium tetrachloronitridomolybdate, C₆H₅N₂[MoNCl₄], was obtained in the form of orange-red crystals from phenyldiazonium chloride and molybdenum nitride chloride in POCl₃ suspension. In boiling di-n-butylether it decomposes to chlorobenzene and the title compound which is obtained in the form of dark red crystals, sensitive to moisture. [MoNCl₃ · O(C₄H₉)₂]₄ can also be obtained directly from MoNCl₃ and dibutylether. It crystallizes in the monoclinic space group P2₁/c with two tetrameric molecules per unit cell. The lattice constants are at ?49°C a = 1 283, b = 1 170, c = 1 922 and β = 94.11°. The crystal structure was determined with the aid of X-ray diffraction data and was refined to a residual index of R = 0.047 for 1951 observed reflexions. In the [MoNCl₃ · O(C₄H₉)₂]₄ molecule the Mo atoms form a square; they are linked with one another via the N atoms with alternating Mo? N distances of 165 and 215 pm, which indicate triple and single bonds, respectively. In the position trans to the shorter Mo?N bond, the ether molecule is bonded by its oxygen atom. The I.R. spectra of C₆H₅N₂[MoNCl₄], C₆H₅N₂[MoCl₆], and [MoNCl₃ · O(C₄H₉)₂]₄ are recorded.     

Synthese und Kristallstruktur von (PPh4)2[Mo2Cl10]

Synthesis and Crystal Structure of (PPh₄)₂[Mo₂Cl₁₀] The title compound is obtained in the reaction of [MoCl₄(Ph? C?C? Ph)]₂ with tetraphenylphosphonium chloride in dichloro methane, forming brown crystals. It is characterized by the i.r. spectrum and a crystal structure analysis by the aid of X-ray diffraction data. The complex crystallizes triclinic in the space group P1 with one formula unit per unit cell. The cell dimensions are a = 1122 pm, b = 1137 pm, c = 1283 pm; α = 63.4°, β = 69.1°, γ = 86.5°. The crystal structure determination (2959 observed, independent reflexions, R = 4.5%) shows the constants of the unit cell to consist of on centrosymmetric anion, two cations and one disordered molecule of dichloro methane. The distance Mo? Mo in the anion is 380 pm, which excludes direct magnetic interaction between the molybdenum atoms.     

Disulfidoverbrückte Halogenokomplexe von Molybdän(V) Kristallstrukturen von (PPh3Me)2[Cl4Mo(μ-S2)2MoCl4] · 2 CH2Cl2 und (PPh4)2[Br4Mo(μ-S2)2MoBr4] · 3 CH2Br2

Disulfido-Bridged Halo Complexes of Molybdenum (V). Crystal Sructures of (PPh₃Me)₂ [Cl₄Mo (μ-S₂)₂MoCl₄]. 2 CH₂Cl₂ and (PPh₄)₂[Br₄Mo(μ-S₂)₂MoBr₄]. 3CH₂Br₂ . Mo(S₂)Cl₃ is prepared by an improved method; the i.r. spectrum is reported. In dichloro methane solution it reacts with (PPh₃Me)Cl forming the complex (PPh₃Me)₂[Cl₄Mo(μ-S₂)₂MoCl₄] · 2 CH₂Cl₂. The bromo complex (PPh₄)₂[Br₄Mo(μ-S₂)₂MoBr₄] · 3 CH₂Br₂ is obtained by reaction of MoBr₄ with S₇NH and subsequent treatment of the reaction mixture with PPh₄Br in CH₂Br₂ solution. Both complexes are characterized by i.r. spectra and structural analyses by X-ray methods. (PPh₃Me)₂[Cl₄Mo(μ-S₂)₂MoCl₄] · 2 CH₂Cl₂ crystallizes monoclinic in the space group P2₁/c with two formula units per unit cell (5268 observed independent reflexions, R = 4.0%). The lattice dimensions are: a = 1097 pm, b = 1510 pm, c = 1591 pm, β = 104.4°. (PPh₄)₂[Br₄Mo(μ-S₂)₂MoBr₄] · 3 CH₂Br₂ crystallizes triclinic in the space group P&1macr; with two formula units per unit cell and the lattice constants a = 1328 pm, b = 1573 pm, c = 1719 pm, α = 95.8°, β = 96.3°, γ = 74.1°. Both compounds are of ionical structure with PPh₃Me^⊕ and PPh₄^⊕ cations, respectively, and anions [X₄MO(μ-S₂)₂MoX₄]^2? very similar to each other. The molybdenum atoms are bridged by two disulfido ligands and are bonded directly with a bond length of 286 pm. The terminal halogen atoms add up to coordination number nine at the molybdenum.