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.     

Trigonal-planare CuX3-Gruppen in Cu2Mo6X14, X = Cl,Br, I

Trigonal Planar CuX₃-Groups in Cu₂Mo₆X₁₄, X = Cl, Br, I Cu₂Mo₆Cl₁₄ (I), Cu₂Mo₆Br₁₄ (II) and Cu₂Mo₆I₁₄ (III) were synthesized by thermal treatment of corresponding mixtures of copper(I) and molybdenum(II) halides. The crystal structures were determined by single crystal X-ray analyses. I and II show isotypism, cubic, Pn3 (no. 201, sec. setting), Z = 4, I: a = 12.772(3) Å, II: a = 13.350(2) Å. III shows a new structural type, orthorhombic, Pbca (No. 61), Z = 4, a = 16.058(3) Å, b = 10.643(2) Å, c = 16.963(3) Å. Trigonal planar CuX₃ units were found in I? III. Structural behaviour relations are discussed, especially with regard to ionic conductivity.     

CsPdCl3 – eine Verbindung mit [Pd2Cl6]-Baugruppen und anorganischem Kation

CsPdCl₃ – A Compound with Isolated [Pd₂Cl₆] Groups and an Inorganic Cation The crystal structure of CsPdCl₃ has been characterized by X-ray powder diffraction methods. Meanwhile it was possible to isolate single crystals and to confirm the structure by single crystal X-ray investigations. CsPdCl₃ crystallizes orthorhombic in space group Ibam (No. 72) with a = 13.724(1), b = 10.579(1), c = 8.499(1) Å, and Z = 8. CsPdCl₃ is a compound with a dinuclear [Pd₂Cl₆]^2– group and a cesium cation. Formerly such groups are only found in combination with large “organic” cations so far.     

Synthese,Eigenschaften und Struktur von oktamerem Titanimidchlorid [Ti(NSiMe3)Cl2]8

Synthesis, Properties, and Structure of Octameric Titanium Imide Chloride [Ti(NSiMe₃)Cl₂]₈ The reaction of TiCl₄ with N(SiMe₃)₃ in sealed glas-tubes yields the titanium imide chloride [Ti(NSiMe₃)Cl₂]₈ ( 1 ). It crystallizes in the space group C2/c with a = 2 704.5(4), b = 1 303.9(1), c = 2 205.4(2) pm, β = 112.78(1)°, Z = 4. In 1 six Ti atoms are linked together by chloro and trimethylsilylimido bridges to form a ring structure. Two TiCl₂-groups are bound in addition to the ring by two imido bridges. Upon annealing at 250°C 1 transformes to the isomeric polymer [Ti(NSiMe₃)Cl₂]_n. Above 250°C 1 decomposes under separation of Me₃SiCl affording TiNCl.     

Darstellung,Kristallstrukturen und Schwingungsspektren von [(Mo6X)Y]2–; Xi = Cl,Br; Ya = NO3, NO2

Synthesis, Crystal Structures, and Vibrational Spectra of [(Mo₆X)Y]^2–; Xⁱ = Cl, Br; Y^a = NO₃, NO₂ By treatment of [(Mo₆X)Y]^2–; Xⁱ = Y^a = Cl, Br with AgNO₃ or AgNO₂ by strictly exclusion of oxygene in acetone the hexanitrato and hexanitrito cluster anions [(Mo₆X)Y]^2–, Y^a = NO₂, NO₃ are formed. X-ray structure determinations of (Ph₄As)₂[(Mo₆Cl)(NO₃)] · 2 Me₂CO ( 1 ) (monoclinic, space group P2₁/n, a = 12.696(3), b = 21.526(1), c = 14.275(5) Å, β = 115.02(2)°, Z = 2), (n-Bu₄N)₂[(Mo₆Br)(NO₃)] · 2 CH₂Cl₂ ( 2 ) (monoclinic, space group P2₁/n, a = 14.390(5), b = 11.216(5), c = 21.179(5)Å, β = 96.475(5)°, Z = 2) and (Ph₄P)₂[(Mo₆Cl)(NO₂)] (3) (monoclinic, space group P2₁/n, a = 11.823(5), b = 13.415(5), c = 19.286(5) Å, β = 105.090(5)°, Z = 2) reveal the coordination of the ligands via O atoms with (Mo–O) bond lengths of 2.11–2.13 Å, and (MoON) angles of 122–131°. The vibrational spectra of the nitrato compounds show the typical innerligand vibrations ν_as(NO₂) (∼ 1500), ν_s(NO₂) (∼ 1270) and ν(NO) (∼ 980 cm^–1). The stretching vibrations ν(N=O) at 1460–1490 cm^–1 and ν(N–O) in the range of 950–1000 cm^–1 are characteristic for nitrito ligands coordinated via O atoms.     

Isotype Strukturen einiger Hexaamminmetall(II)-halogenide von 3d-Metallen: [V(NH3)6]I2, [Cr(NH3)6]I2, [Mn(NH3)6]Cl2, [Fe(NH3)6]Cl2, [Fe(NH3)6]Br2, [Co(NH3)6]Br2 und [Ni(NH3)6]Cl2

The Structures of some Hexaammine Metal(II) Halides of 3 d Metals: [V(NH₃)₆]I₂, [Cr(NH₃)₆]I₂, [Mn(NH₃)₆]Cl₂, [Fe(NH₃)₆]Cl₂, [Fe(NH₃)₆]Br₂, [Co(NH₃)₆]Br₂ and [Ni(NH₃)₆]Cl₂ Crystals of yellow [V(NH₃)₆]I₂ and green [Cr(NH₃)₆]I₂ were obtained by the reaction of VI₂ and CrI₂ with liquid ammonia at room temperature. Colourless crystals of [Mn(NH₃)₆]Cl₂ were obtained from Mn and NH₄Cl in supercritical ammonia. Colourless transparent crystals of [Fe(NH₃)₆]Cl₂ and [Fe(NH₃)₆]Br₂ were obtained by the reaction of FeCl₂ and FeBr₂ with supercritical ammonia at 400°C. Under the same conditions orange crystals of [Co(NH₃)₆]Br₂ were obtained from [Co₂(NH₂)₃(NH₃)₆]Br₃. Purple crystals of [Ni(NH₃)₆]Cl₂ were obtained by the reaction of NiCl₂ · 6H₂O and NH₄Cl with aqueous NH₃ solution. The structures of the isotypic compounds (Fm3 m, Z = 4) were determined from single crystal diffractometer data (see “Inhaltsübersicht”). All compounds crystallize in the K₂[PtCl₆] structure type. In these compounds the metal ions have high-spin configuration. The orientation of the dynamically disordered hydrogen atoms of the ammonia ligands is discussed.     

Darstellung und Einkristall-Strukturanalyse von Hexachloro-μ-dichloro-bis[N-(trimethylsilyl)imidazol]dititan-Chloroform (1/2) [Ti2Cl8(C6H12N2Si)2] · 2 CHCl3

Synthesis and Crystal Structure Determination of Hexachloro-μ-dichloro-bis[N-(trimethylsilyl)imidazol]dititanium Chloroform (1/2) Hexachloro-μ-dichloro-bis[N-(trimethylsilyl)-imidazol]dititanium chloroform (1/2) 1 has been prepared by the reaction of titanium tetrachloride with N-trimethylsilylimidazole (NTMSI) in chloroform solution as orange crystals. The structure consists of two distorted TiCl₅N octahedrons, which are connected by two chlorine atoms via common edges to a centrosymmetric dimer [Ti₂Cl₈(NTMSI)₂] · 2 CHCl₃. The N-trimethylsilylimidazole ligands each are located at one axial position of each octahedron, whereas the equatorial positions are occupied by the chloro ligands. The results presented are discussed assuming a gradual formation of an 1 : 1 and 1 : 2 adduct.     

Tl4Pd3Cl10 – eine Verbindung mit neuartiger [(PdCl2Cl2/2)4]4–‐Baugruppe

Tl₄Pd₃Cl₁₀ – A Compound with a New [(PdCl₂Cl_2/2)₄]^4– Group Single crystals of Tl₄Pd₃Cl₁₀ can be obtained by hydrothermal synthesis. They show tetragonal symmetry with lattice parameters a = 15.956(1) Å and c = 14.146(1) Å, Z = 8 and space group I42d (No. 122). The atomic arrangement of Tl₄Pd₃Cl₁₀ is explored by X‐ray crystal structure analysis. Tl₄Pd₃Cl₁₀ is the first example of a new structural type with a hitherto not isolated tetramer [(PdCl₂Cl_2/2)₄]^4– group.     

Elektronenmikroskopische Untersuchungen zur Realstruktur von La2CeTaO6Cl3 und dessen thermischem Abbauprodukt La2CeCe TaO6Cl3−x

High Resolution Electron Microscopy Investigations of La₂CeTaO₆Cl₃ and its Thermal Decomposition Product La₂Ce Ce TaO₆Cl_3?x The thermal decomposition of the hexagonal La₂CeTaO₆Cl₃ led to a mixed-valent product La₂CeCe TaO₆Cl_3?x with a complicated monoclinic structure. The detailed inspection shows two subunits A and B, which form the monoclinic unit cell by a ABAB sequence. The subunit A is almost identical to the hexagonal cell of the starting material while subunit B has additional Ln- and Cl-positions. For this reason, the main structure features of the monoclinic compound and the starting material are related, which is clearly seen in the electron microscopy investigations. As might be expected from the relationship between the subunits A and B one can observe defects in the monoclinic compound arising from the various possibilities of combining these building elements. We also found structure defects in the hexagonal starting material, which are caused by the presence of the subunit B.     

Das prismatische Te62+-Ion in der Struktur von Te6(NbOCl4)2

The Prismatic Te₆²⁺ Ion in the Structure of Te₆(NbOCl₄)₂ Te₆(NbOCl₄)₂ is obtained from Te, TeCl₄ and NbOCl₃ at 200°C. It crystallizes triclinic, space group P1 (a = 915,5(4) pm, b = 1655,3(6) pm, c = 3134,4(9) pm, α = 42,62(2)°, β = 117,12(6)°, γ = 138,24(8)°). The crystal structure analysis shows, that the structure is built of one-dimensional polymeric [NbOCl₄^?] chains in which the monomers are linked via linear O? Nb? O-bridges and from discrete Te₆²⁺ polycations that are also arranged in strands, but without significant interactions. The structure is closley related but not isotypic to the previously reported tungsten containing analogue Te₆(WOCl₄)₂ (monoclinic, P2₁/c). A comparison of the two structures shows that rotations of the cationic strands relative to the anionic strands lead to different cation-anion interactions.     

Reaktionen von [B12H12–n(OH)n]2–, n = 1, 2 mit Säuredichloriden und Kristallstruktur von Cs2[1,2-B12H10(ox)] · CH3OH

Reactions of [B₁₂H_12–n(OH)_n]^2–, n = 1, 2 with Acid Dichlorides and Crystal Structure of Cs₂[1,2-B₁₂H₁₀(ox)] · CH₃OH By treatment of [B₁₂H₁₁(OH)]^2– with organic and inorganic acid dichlorides in acetonitrile the bridged dicluster compounds [B₁₂H₁₁(ox)B₁₂H₁₁)]^4– ( 1 ), [B₁₂H₁₁(p-OOCC₆H₄COO)B₁₂H₁₁]^4– ( 2 ), [B₁₂H₁₁(m-OOCC₆H₄COO)B₁₂H₁₁]^4– ( 3 ), [B₁₂H₁₁(SO₃)B₁₂H₁₁]^4– ( 4 ), [B₁₂H₁₁(SO₄)B₁₂H₁₁]^4– ( 5 ) are obtained in good yields. The dihydroxododecaborates [1,2-B₁₂H₁₀(OH)₂]^2– and [1,7-B₁₂H₁₀(OH)₂]^2– afford clusters with an anellated ring: [1,2-B₁₂H₁₀(ox)]^2– ( 6 ), [1,2-B₁₂H₁₀(SO₄)]^2– ( 7 ) and [1,7-B₁₂H₁₀(OOC(CH₂)₈COO)]^2– ( 8 ). Isomerically pure [1,7-B₁₂H₁₀(OH)₂]^2– ( 9 ) is formed by reaction of (H₃O)₂[B₁₂H₁₂] with ethylene glycol. All new compounds are characterized by vibrational, ¹¹B, ¹³C and ¹H NMR spectra. The crystal structure of Cs₂[1,2-B₁₂H₁₀(ox)] · CH₃OH (monoclinic, space group P 2₁/c, a = 9.616(2), b = 10.817(1), c = 15.875(6) Å, β = 95.84(8)°, Z = 4) reveals a distortion of the B₁₂ icosahedron caused by the anellated six-membered heteroring.     

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.     

Clusteraufbau durch Photolyse von R3PAuN3. VIII. Synthese und Kristallstruktur von [(Ph3PAu)5Mo(CO)4]PF6 · CH2Cl2 und (Ph3PAu)3Co(CO)3

Cluster Synthesis by Photolysis of R₃PAuN₃. VIII. Synthesis and Crystal Structure of [(Ph₃PAu)₅Mo(CO)₄]PF₆ · CH₂Cl₂ and (Ph₃PAu)₃Co(CO)₃ Photolysis of a mixture of Ph₂PAuN₃ and Mo(CO)₆ in THF yields [(Ph₃PAu)₅Mo(CO)₄]⁺ (1), which can be crystallized from CH₂Cl₂/diisopropylether as orange 1 · PF₆ · CH₂Cl₂ with the space group P2₁/c and a = 1681.4(5), b = 2215.6(12), c = 2761.5(9) pm, β = 91.54(3)°, Z = 4. The Au₅Mo center of cluster 1 forms a capped trigonal bipyramid with the Mo atom in equatorial position and almost equal Mo? Au distances between 279.9(5) and 284.6(7) pm to all five Au atoms. The Au? Au distances range from 272.2(4) to 301.3(4) pm. The Mo(CO)₄ group causes three v(C0) at 1975, 1915 and 1890cm^?1. Reaction of Ph₃PAuCo(CO)₄ with Ph₃PAuPF₆ affords the known cluster cation [(Ph₃PAu)₄Co(CO)₃]⁺ in high yield. It can be degraded with C1^? to the neutral cluster (Ph₃PAu)₃Co(CO)₃ (2). 2 forms air stable, yellow crystals with the space group P2₁/n and a = 1359.4(4), b = 2041.0(5), c = 1853.2(6)pm, β = 91.47(1)°, Z = 4. The Au₃Co core of 2 has a tetrahedral structure with distances Co? Au between 250.4(1) and 254.0(2) pm and Au? Au between 279.5(1) and 285.1(1) pm. v(C0) are observed at 1963, 1905 and 1891 cm^?1. Reaction of 2 with [(Ph₃PAu)₄Co(CO)₃]⁺ yields the condensed cluster [(Ph₃PAu)₆AuCo₂(CO)₆]⁺.     

[Mg3Cl5(Et2O)6]+: Darstellung,Strukturbestimmung und ab-initio-Untersuchungen

[Mg₃Cl₅(Et₂O)₆]⁺: Synthesis, Structure, and Ab-Initio Calculations The cation [Mg₃Cl₅(Et₂O)₆]⁺ of a chlorogallat has been prepared in a reaction of Ga₂Cl₄ with MgCp and was characterized by a X-ray single-crystal structure analysis. For understanding of the conditions of formation of neutral and charged magnesium chlorids and of the processes in the complex reaction system ab-initio calculations were performed.     

Über die Reaktion von Tellur mit Wolframhalogeniden: Synthese und Struktur von Te7WOCl5, einer Verbindung mit einem polymeren Tellur-Kation

On the Reaction of Tellurium with Tungsten Halides: Synthesis and Crystal Structure of Te₇WOCl₅, a Compound with a Polymer Tellurium Cation The reaction of tellurium with WOCl₄ in the presence of a large excess of WCl₆ in a sealed evacuated glass ampoule at 150°C yields beside the main product Te₈(WCl₆)₂ a small amount of Te₇WOCl₅. The crystal structure determination (orthorhombic space group Pcca, lattice parameters at 173 K: a = 2 596.5(9) pm, b = 810.0(3) pm, c = 775.7(2) pm) shows that Te₇WOCl₅ is built of one-dimensional band shaped polymeric tellurium cations, one-dimensional associated pyramidal WOCl₄^? anions and of isolated Cl^? anions. Te₇WOCl₅ can thus be formulated as [Te₇²⁺]_n [WOCl₄^?]_n (Cl^?). The structure is closely related but not isotypic to the bromine containing analogue Te₇WOBr₅. The difference between the two structures lies in different directions of the polar [WOX₄^?]_n chains (X = Cl, Br). The strongly elongated thermal ellipsoid of one tellurium atom is shown to be caused by thermal vibration by determing the crystal structure of Te₇WOCl₅ at three different temperatures (223, 173 and 123 K). All displacement parameters of all atoms can be extrapolated to zero for 0 K.     

Darstellung,Kristallstruktur und spektroskopische Eigenschaften der Clusteranionen [(Mo6Br)X]2− mit Xa = F,Cl, Br,I

Synthesis, Crystal Structure and Spectroscopic Properties of the Cluster Anions [(Mo₆Br )X ]^2? with X^a = F, Cl, Br, I The tetrabutylammonium (TBA), tetraphenylphosphonium (TPP) and tetraphenylarsonium (TPAs) salts of the octa-μ₃-bromo-hexahalogeno-octahedro-hexamolybdate(2?) anions [(Mo₆Br)X]^2? (X^a = F, Cl, Br, I) are synthesized from solutions of the free acids H₂[(Mo₆Br)X] · 8 H₂O with X^a = Cl, Br, I. The crystal structures show systematic stretchings in the Mo? Mo bond length and a slight compression of the Brⁱ₈ cube in the F^a to I^a series. The cations do not change much. The i.r. and Raman spectra show at 10 K almost constant frequencies of the (Mo₆Brⁱ₈) cluster vibrations, whereas all modes with X^a ligand contribution are characteristically shifted. The most important bands are assigned by polarization measurements and the force constants are derived from normal coordinate analysis. The ⁹⁵Mo nmr signals are shifted to lower field with increasing electronegativity of the X^a ligands. The fluorine compound shows a sharp ¹⁹F nmr singlet at ?184.5 ppm.     

Ein oktaedrischer Niobcluster mit sechs terminalen Azidgruppen: Die Struktur von Rb4[Nb6Br12(N3)6](H2O)2

An Octahedral Niobium Cluster containing Six Terminal Azide Groups: The Structure of Rb₄[Nb₆Br₁₂(N₃)₆](H₂O)₂ Six terminal halide ligands of [Nb₆Br₁₂Br₆]^4? can be substituted in solution by azide ions. Single-crystals of Rb₄[Nb₆Br₁₂(N₃)₆](H₂O)₂ were obtained during the evaporation of the water/methanol solvent, and structurally characterized by X-ray methods: Space group P2₁/c, Z = 2, a = 970.8(5) pm, b = 1525.4(7) pm, c = 1280.0(7) pm, β = 97.15(6)°. The [Nb₆Br₁₂(N₃)₆]^4? ions contain six terminal azide groups at the corners of the octahedral niobium cluster (d _Nb–N = 227 pm). The [Nb₆Br₁₂(N₃)₆]^4? ions are interconnected by Rb⁺ and H₂O. Crystals of Rb₄[Nb₆Br₁₂(N₃)₆](H₂O)₂ are explosive towards heat or mechanic pressure.     

(Bzl4P)2[Bi2I8] – ein Iodobismutat mit fünffach koordiniertem Bi3+‐Ion

(Bzl₄P)₂[Bi₂I₈] – an Iodobismuthate with Penta‐coordinated Bi³⁺ Ions (Bzl₄P)₂[Bi₂I₈] ( 1 , Bzl = –CH₂–C₆H₅) is the first iodobismuthate showing square pyramidal coordination of the Bi³⁺ ion. The anion structure of 1 is compared with that of (Ph₄P)₂[Bi₂I₈(thf)₂] ( 2 ), in which the vacant coordination sites in 1 are occupied by THF ligands. (Bzl₄P)₂[Bi₂I₈] ( 1 ): Space group P1 (No. 2), a = 1300.6(6), b = 1316.8(6), c = 2157.0(9) pm, α = 78.66(3), β = 87.17(3), γ = 60.62(3)°, V = 3151(2)_.10⁶ pm³; (Ph₄P)₂[Bi₂I₈(thf)₂] ( 2 ): Space group P1 (No. 2), a = 1146.5(1), b = 1181.2(1), c = 1249.2(1) pm, α = 92.28(1), β = 105.71(1), γ = 95.67(1)°, V = 1616.6(2)_.10⁶ pm³.     

[ReIII(thiourea-S)6]Cl3 · 4 H2O and [ReIII(N-methylthiourea-S)6]Cl3 as Precursors to other ReIII Complexes: a Kinetic Study in Aqueous Media. Crystal Structure of [ReIII(N-methylthiourea-S)6](PF6)3 · H2O

Capability of [Re^III(tu-S)₆]Cl₃, where tu = thiourea, as a precursor to other Re^III complexes by ligand substitution in aqueous medium is studied. For the decomposition of [Re(tu-S)₆]Cl₃, experiments suggest pseudo first order kinetics and observed rate constants vary from 1.3 × 10^–2 to 9.6 × 10^–2 min^–1 in the pH range 2.80–5.04. Experiments in presence of incoming ligand (ethylendiaminetetraacetic acid or diethylentriaminepentaacetic acid) show that ligand substitution is significantly slower than decomposition of the precursor, even when pH and temperature are modified. Similar results were obtained working with [Re^III(Metu-S)₆]Cl₃, where Metu = N-methylthiourea. Molecular structure of [Re^III(Metu-S)₆](PF₆)₃ · H₂O was determined by single crystal X-ray diffractometry. The coordination polyhedron around the Re ion is a distorted octahedron. The six methylthiourea ligands are bonded to the metal through the sulfur atoms [bond lengths range from 2.409(2) to 2.451(2) Å].     

Synthesis of a new salt containing polyoxometallate anion and M?Cu?S cluster cation [MS4Cu4(γ-MePy)8][M6O19] (M = Mo,W). Crystal structure of [WS4Cu4(γ-MePy)8] [W6O19]

Reactions of (NH₄)₂MS₄, AgBr and CuBr in γ-methylpyridine produced one new compound, [MS₄Cu₄(γ-MePy)8][M₆O₁₉] (1, M = W; 2 , M = Mo), of which 1 was characterized by single crystal X-ray analysis. The crystal data: orthorhombic, Pbcn, a = 15.434(4), b = 16.732(2), c = 28.657(7) Å, V = 7400.8(8) ų, Z = 4 , R = 0.072 for 3121 independent data. The compound is the first example which contains both polyoxotungstate anion and heteropolynuclear cluster cation. In the structure of the cation four edges of the tetrahedral WS^2?₄ core are coordinated by four copper atoms, giving a WS₄Cu₄ aggregate of approximate D_2h symmetry. The differences between the reaction of Cu⁺ with MS^2?₄ and that of Ag+ with MS^2?₄ in pyridine and its derivatives are discussed.