Darstellung und Schwingungsspektren von trans-[Pt(acac)2X2] (X  Cl,Br, I,SCN, SeCN,N3)

Preparation and Vibrational Spectra of trans-[Pt(acac)₂X₂] (X ? Cl, Br, I, SCN, SeCN, N₃) By electrolytical oxidation of [Pt(acac)₂] in presence of chloride or bromide, dissolved in dichlormethane, trans-[Pt(acac)₂X₂], X ? Cl, Br, are formed. On treatment of trans-[Pt(acac)₂I₂] with silver pseudohalides trans-[Pt(acac)₂X₂], X ? SCN, SeCN, N₃, are obtained. Beside the nearly persistent bands of coordinated acetylacetonate in the Raman spectra the intensive and sharp symmetric, in the IR spectra the corresponding antisymmetric stretching vibration of the X? Pt? X axis is observed. The observance of the rule of mutual exclusion proves the complexes to belong to point group D_2h. From the resonance Raman spectrum of trans-[Pt(acac)₂I₂] for v_s (Pt? I), A_g, the harmonic frequency ω₁ = 142.45 cm^?1 and the inharmonicity constant x₁₁ = 0.48 cm^?1 is calculated. In the Raman spectrum of trans-[Pt(acac)₂Cl₂] v_s (Pt? Cl) is splitted by the isotops ³⁵Cl/³⁷Cl into the triplet 340, 335, 330 cm^?1 giving the force constant f_PtCl = 2.01 N/cm.     

Alternativ-Liganden. III. Koordinatives verhalten von chelatliganden des typs me2XSi(Me2)CH2XMe2 (X  N und/oder P: Me  CH3)

Co-ordinative Properties of Chelating Ligands of the Type Me₂XSi(Me₂)CH₂XMe₂ (X ? N and/or P; Me ? CH₃) The reactions of the ligands L ? Me₂XSi(Me₂)CH₂XMe₂ (X ? N and/or P; Me ? CH₃) with M(CO)₆ and M(CO)₄norbor (norbor ? norbornadiene) (M ? Cr, Mo), respectively, yield derivatives of the types M(CO)₅L, M(CO)₄L, and M(CO)₄L₂, respectively. M(CO)₅L compounds are formed from the hexacarbonyls with Me₂NSiMe₂CH₂PMe₂, whereas the ligand Me₂NSiMe₂CH₂NMe₂ does not afford analogous derivatives under the same conditions. Even on substitution of the diene-ligand in M(CO)₄norbor by Me₂NSiMe₂CH₂PMe₂ the chelate complexes M(CO)₄NMe₂SiMe₂CH₂PMe₂ are not obtained, but the cis-disubstituted products M(CO)₄[PMe₂CH₂SiMe₂NMe₂]₂ with phosphorus acting as donor atom are produced. The ligands Me₂PSiMe₂CH₂XMe₂(X ? N, P) give the chelate complexes M(CO)₄PMe₂SiMe₂CH₂XMe₂ in high yields. The new compounds were identified by analytical and spectroscopic (PMR, IR, mass spectra) methods.     

Zur solvensfreien Darstellung von Tetramethylammoniumsalzen: Synthese und Charakterisierung von [N(CH3)4]2[C2O4], [N(CH3)4][CO3(CH3)], [N(CH3)4][NO2], [N(CH3)4][CO2H] und [N(CH3)4][O2C(CH2)2CO2(CH3)]

Solvent-free Synthesis of Tetramethylammonium Salts: Synthesis and Characterization of [N(CH₃)₄]₂[C₂O₄], [N(CH₃)₄][CO₃CH₃], [N(CH₃)₄][NO₂], [N(CH₃)₄][CO₂H], and [N(CH₃)₄][O₂C(CH₂)₂CO₂CH₃] A general procedure to synthesize tetramethylammonium salts is presented. Several tetramethylammonium salts were prepared in a crystalline state by solvent-free reaction of trimethylamine and different methyl compounds at mild conditions: [N(CH₃)₄]₂[C₂O₄] (cubic; a = 1 114.8(3) pm), [N(CH₃)₄][CO₃CH₃] (P2₁/n; a = 813.64(3), b = 953.36(3), c = 1 131.3(4) pm, β = 90.03(1)°), [N(CH₃)₄][NO₂] (Pmmn; a = 821.2(4), b = 746.5(3), c = 551.5(2) pm), [N(CH₃)₄][CO₂H] (Pmmn; a = 792.8(7), b = 791.7(3), c = 563.3(4) pm) and [N(CH₃)₄][O₂C(CH₂)₂CO₂CH₃] (P2₁; a = 731.1(2), b = 826.4(3), c = 1 025.2(3) pm, β = 110.1(1)°). The tetramethylammonium salts were characterized by IR-spectroscopy and X-ray diffraction. The crystal structures of the methylcarbonate and the nitrite are described.     

Silaethene. III. Versuche zur Darstellung und spektroskopischen Charakterisierung von H2SiCH2, D2SiCH2 und Me(H)SiCH2

Silaethenes. III. Preparation and Spectroscopic Characterization of H₂Si?CH₂, D₂Si?CH₂, and Me(H)Si?CH₂ H₂Si?CH₂ and D₂Si?CH₂ are formed together with ethene and propene by gas phase pyrolysis at low pressure (10^?2–10^?3 mbar) from the corresponding mono- or 1,3-disilacyclobutanes in good yield and are characterized by i.r. and mass spectroscopic methods. Formation of propene can be explained by following reactions of the silaethene intermediate using a “head-to-head” mechanism. H₂Si?CH₂ can be stored at ?196°C for several months and can be transferred by trap-to-trap distillation in a vacuum system. Similar results are obtained for .     

Zur Darstellung von Yttriumhydridhalogeniden YXHn (X  Cl,Br)

On the Preparation of Yttrium Hydride Halides YXH_n (X ? Cl, Br) The compounds YCl and YBr described in a previous paper as “monohalides” in reality are hydridehalides YClH_n and YBrH_n with the H-concentration in the range 0.7 ≤ n ≤ 1.0. Dehydrogenation experiments on YCIH_0.7 in all cases resulted in heterogeneous products consisting of YCl₃, Y and YClH_n. With increasing hydrogen content the c-lattice parameter decreases. Observed minimal c-lattice parameter is 2727.0(7) pm (for n ≈? 1), maximum c-lattice parameter is 2752.3(4) pm (for n ≈? 0.68). YBrH_n crystallizes in the ZrBr-structure type, YClH_n for 0.7 ≤ n ≤ 0.8 in the ZrBr-type, for 0.8 ≤ n ≤ 1.0 in the ZrCl-type. YXH_n (X ? Cl, Br) has a graphite like colour and in H atmosphere can be hydrogenated to the colourless compound YXH₂. YClH₂ and YBrH₂ are isotypic with TbBrD₂. A miscibility gap was found between YClH_1.0 and YClH_2.0.     

Kristallstruktur und Schwingungsspektrum von Tris-trichlorophosphazeno-carbenium-hexachloroantimont [C(N  PCl3)3]+SbCl6−

Crystal Structure and Vibrational Spectrum of Tris-trichlorophosphazeno-carbenium-hexachloroantimonate [C(N?PCl₃)₃]⁺SbCl₆^? [C(N?PCl₃)₃]SbCl₆ crystallizes in the space group P1 with the lattice constants a = 903 b = 1046, c = 1307 pm and α = 94.8, β = 88.3, γ = 103.8°. Using X- ray diffraction data, the crystal structure was determined and refined to a residual index of 0.027. The structure consists of octahedral SbCl₆^? ions and [C(N?PCl₃)₃]⁺ ions having approximately C_3h symmetry; the atoms C, N, P, and one Cl per PCl₃ group lie approximately in a plane. The i. R. and Raman spectrum was registered and assigned.     

Darstellung,Kristallstrukturen, Schwingungsspektren und Normalkoordinatenanalyse von [(Mo6Br)Y]2−; Ya  CN,NCS

Preparation, Crystal Structures, Vibrational Spectra, and Normal Coordinate Analysis of [(Mo₆Br )Y ]^2?; Y^a ? CN, NCS By treatment of [(Mo₆Br)Br^a₆]^2? with AgNO₃ in acetone and addition of KCN or KNCS the hexacyano and hexaisothiocyanato derivates [(Mo₆Br)Y]^2?, Y^a ? CN, NCS are formed. X-ray structure determinations of (Ph₄P)₂ [(Mo₆Br)(CN)^a₆]·4H₂ O ( 1 ) (triclinic, spacegroup P1, a = 11.63(3), b = 11.85(1), c = 14.23(5) Å, α = 71.8(1)°, β = 67.6(3)°, γ = 62.8(1)°, Z= 1) and (n-Bu₄N)₂[(Mo₆Br ⁱ₈)(NCS)^a₆] · 2Et₂O ( 2 ) (monoclinic, spacegroup P2₁/n, a = 11.483(3), b = 16.348(5), c = 20.059(6) Å, β= 95.44(3)°, Z = 2) have been performed. The via C coordinated cyano ligands of ( 1 ) reveal facial groups with (MoCN) angles of 168.0–171,5° and 174.1°–175.7°. In ( 2 ) the via N coordinated isothiocyanato groups at the apical positions show MoNC-angles of 164.4°, the equatorial angles are 172.7–173.5°. Using the molecular parameters of the X-ray determinations the 10 K IR and Raman spectra of the (n-Bu₄N) cluster salts are assigned by normal coordinate analyses based on a modified valence force field. The valence force constants are f_d(MoMo) = 1.41 (CN^a), 1.43 (NCS^a), f_d (MoBrⁱ) = 0.97 (CN^a), 0.96 (NCS^a), f_d(MoC) = 1.62, f_d(Mo-N) = 2.09 mdyne/Å.     

Synthese und Struktur von MII[AuF4]2 (MII  Cd,Hg)

Synthesis and Structure of M^II[AuF₄]₂ (M^II ? Cd, Hg) Cd[AuF₄]₂ and the isotypic compound Hg[AuF₄]₂, both are yellow, crystallize tetragonal in the space-group P4/mcc-D (No. 124) with a = 575.0/575.6 pm, c = 1034.8/1042.3 pm and Z = 2. The single-crystals were obtained by solid-state reactions in goldtubes.     

Darstellung und Kristallstrukturen von Ag[N(CN)2](PPh3)2, Cu[N(CN)2](PPh3)2 und Ag[N(CN)2](PPh3)3

Preparation and Crystal Structures of Ag[N(CN)₂](PPh₃)₂, Cu[N(CN)₂](PPh₃)₂, and Ag[N(CN)₂](PPh₃)₃ The coordination compounds Ag[N(CN)₂](PPh₃)₂ ( 1 ), Cu[N(CN)₂](PPh₃)₂ ( 2 ), and Ag[N(CN)₂](PPh₃)₃ ( 3 ) are obtained by the reaction of AgN(CN)₂ or CuN(CN)₂ with triphenylphosphane in CH₂Cl₂. X‐ray structure determinations were performed on single crystals of 1 , 2 , and 3 · C₆H₅Cl. The three compounds crystallize monoclinic in the space group P2₁/n with the following unit cell parameters. 1 : a = 1216.07(9), b = 1299.5(2), c = 2148.4(3) pm, β = 99.689(13)°, Z = 4; 2 : a = 1369.22(10), b = 1257.29(5), c = 1888.04(15) pm, β = 94.395(7)°, Z = 4; 3 · C₆H₅Cl: a = 1276.6(4), b = 1971.7(3), c = 2141.3(5) pm, β = 98.50(3)°, Z = 4. In all structures the metal atoms have a distorted tetrahedral coordination. The crystal structure of 3 · C₆H₅Cl shows monomeric molecular units with terminal coordinated dicyanamide. The crystal structure of 1 is built up by dinuclear units, which are bridged by dicyanamide ligands. However, the crystal structure of 2 corresponds to a onedimensional coordination polymer, bridged by dicyanamide anions.     

Darstellung von Nonahalogenodiplatinaten(IV), [Pt2X9]−, X  Cl,Br Spektroskopische Charakterisierung,Normalkoordinatenanalyse und Kristallstruktur von (PPN)[Pt2Br9]

Preparation of the Nonahalogenodiplatinates(IV), [Pt₂X₉]^?, X ? Cl, Br Spectroscopic Characterization, Normal Coordinate Analysis, and Crystal Structure of (PPN)[Pt₂Br₉] On heating the tetrabutylammonium salts (TBA)₂[PtX₆], with trifluoroacetic acid the nonahalogenodiplatinates(IV) (TBA)[Pt₂X₉], with X ? Cl, Br are formed. The X-ray structure determination on (PPN)[Pt₂Br₉] (orthorhombic, space group Pca2, Z = 4) shows for the anions pairs of face-sharing octahedra with nearly D_3h symmetry. The mean terminal and bridging Pt? Br bond lengths are determined to be 2.42 and 2.52 Å, respectively. The electrostatic interaction of the Pt atoms results in the Pt? Pt distance of 3.23 Å and an elongation as it has been forecasted by the MO scheme for d⁶ systems. Using the structural data a normal coordinate analysis based on a general valence force field for [Pt₂Br₉]^? has been performed, revealing a good agreement of the calculated frequencies with the bands observed in the IR and Raman spectra. The stronger bonding of the terminal as compared to the bridging ligands is shown by the valence force constants, f_a(Br₁) = 1,55 > f_d(Br_b) = 0,93 mdyn/ Å.     

Synthese,Strukturen und Reaktivität von [(2,4,6-Ph3C6H2)Te(μ2-O)X]2 (X  Br und I)

Synthesis, Structures, and Reactivity of [(2,4,6-Ph₃C₆H₂)Te(μ₂-O)X]₂ (X ? Br, I) [(2,4,6-Ph₃C₆H₂)Te]₂ reacts with iodine affording the aryltellurenic halide (2,4,6-Ph₃C₆H₂)TeI, which is oxidized by oxygen to yield [(2,4,6-Ph₃C₆H₂)Te(μ₂-O)I]₂. It crystallizes with two molecules of dichloromethane in the monoclinic space group P2₁/c with a unit cell of the dimensions a = 911.3(4); b = 1153.3(2); c = 2244.1(9) pm; β = 93.53(2)°, Z = 2). The analogues bromo compound [(2,4,6-Ph₃C₆H₂)Te(μ₂-O)Br]₂ is obtained by the reaction of [(2,4,6-Ph₃C₆H₂)Te(μ₂-O)I]₂ with NH₄Br. It crystallizes with two molecules of xylene in the monoclinic space group P2₁/n (a = 1067.5(5); b = 1018.4(4); c = 2486.5(8) pm; β = 101.71(2)°; Z = 2). Both compounds are built up by two (2,4,6-Ph₃C₆H₂)TeX units (X ? Br, I) which are linked by two oxgen bridges to form centrosymmetric molecules. The Te? O? Te angles are 102°. Distinct Te? O bond lengths have been found (191.4(2) and 208.6(2) pm in [(2,4,6-Ph₃C₆H₂)Te(μ₂-O)I]₂ and 189.8(4)/208.4(5 pm in the bromo compound).     

Über die Existenz von Verbindungen des Typs Hg2XA (X  Halogen,A  Anion ≠ Halogen) und Hg2XY (X und Y Halogen)

Existence of Hg₂XA (X ? Halide, A ? Anion ≠ Halide) and Hg₂XY Compounds (X and Y Halide) Investigations in molten mercuric bromide HgBr₂ [1, 2] and comparing considerations between mercuric and mercurous chemistry lead to the till now unknown or less investigated compounds Hg₂XA and Hg₂XY (X, Y halide; A anion ≠ halide). Using TGA and DTA measurements in order to improve the reaction conditions Hg₂XClO₄ salts could be synthesized, whereas the hydrogene sulfates Hg₂XHSO₄ are formed in concentrated sulfuric acid (crystalline, instable by solvent removing). Powder diagrams and spectrochemical investigations point our that the lattices of the isolated mixed halides Hg₂BrCl, Hg₂BrI, and Hg₂ClI contain not only the pure molecules Hg₂X₂ and Hg₂Y₂ but also the mixed molecules Hg₂XY. Final statements need X-ray investigations.     

Zweikernige Cobalt(III)-Komplexe mit unsymmetrischen Azidbrücken: [Co (N3)X2en]2 mit X  Cl,Br, NO3, N3

Binuclear Cobalt(III) Complexes Containing Asymmetric Azide Bridges: [Co(N₃)X₂en]₂; X ? Cl, Br, NO₃ or N₃ The preparation and the properties of the title compounds are described. According to their IR spectra asymmetric azide bridges are present in these complexes.     

Calcium-diazido-di-dimethylformamid,Ca(N3)2[OCHN(CH3)2]2 Darstellung und Kristallstruktur

Calcium-diazido-di-dimethylformamide, Ca(N₃)₂[OCHN(CH₃)₂]₂, Preparation and Crystal Structure The title compound was prepared by the reaction of Ca(N₃)₂ with OCHN(CH₃)₂ in aqueous solution. The crystals are orthorhombic, a = 968.5(3), b = 1 479.6(15), c = 1 945.3(17) pm, space group Cmca, Z = 8. The crystal structure was determined by single crystal X-ray diffraction techniques and refined to R = 0.061. Calcium atoms are surrounded by four terminal nitrogen atoms of azide groups and by two oxygen atoms of dimethylformamide (DMF). The polyhedra around Ca are octahedra which are linked via four azide groups to form Ca(N₃)₂ layers. The DMF molecules are located between these layers, and they are highly disordered.