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 .     

Synthese und Kristallstrukturen der silylierten Tris-Phosphanimine R?C(CH2PPh2NSiMe3)3 mit R  H und CH3

Synthesis and Crystal Structures of the Silylated λ⁵-Phosphazenes R? C(CH₂PPh₂NSiMe₃)₃ with R = H and CH₃ The title compounds are obtained by Staudinger reaction from the corresponding tripodal phosphanes R? C(CH₂PPh₂)₃ and trimethylsilylazide. Both complexes are characterized by their IR and NMR spectra and by crystal structure analyses. H? C(CH₂PPh₂NSiMe₃)₃ ( 1 ): Space group P2₁/c, Z = 4, structure determination with 7833 independent reflections, R = 0.055. Lattice dimensions at ?50°C: a = 1399.5, b = 2311.4, c = 1678.9 pm, β = 112.92°. CH₃? C(CH₂PPh₂NSiMe₃)₃ ( 2 ): Space group P1 , Z = 2, structure determination with 9251 independent reflections, R = 0.057. Lattice dimensions at ?50°C: a = 1276.5, b = 1386.9, c = 1790.2 pm; α = 85.55°, β = 69.39°, γ = 62.99°. 1 and 2 form monomeric molecules which are distinguished by their conformation.     

Über die Kristallstrukturen von CH3PF2H+AsF6− und CH3PF2H+SbF6− und eine einfache Darstellung von CH3PF2

On the Crystal Structures of CH₃PF₂H⁺AsF₆^? and CH₃PF₂H⁺SbF₆^? and a simple Method for Preparation of CH₃PF₂ A simple method for preparation of CH₃PF₂ from CH₃PCl₂ is reported. The phosphonium salts CH₃PF₂H⁺MF₆^? are obtained by the reaction of CH₃PCl₂ with superacidic systems HF/MF₅ (M = As, Sb). CH₃PF₂H⁺SbF₆^? crystallizes in the space group P1 with a = 548.4(4) pm, b = 695.5(8) pm, c = 960.2(9) pm, α = 94.68(5)°, β = 97.19(6)°, γ = 94.41(6)° and Z = 2. CH₃PF₂H⁺SbF₆^? crystallizes in P1 with a = 554.3(3), b = 724.2(4), c = 970.4(5), α = 94.73(4)°, β = 96.14(5)°, γ = 95.30(4)°.     

Darstellung der Dichlormethyleniminium-Salze Cl2CNClH+ MF6− und Cl2CNClCH3+ MF6− (M = As,Sb) und Kristallstruktur von Dichlormethyleniminiumhexachloroantimonat Cl2CNH2+SbCl6−

Synthesis of the Dichloromethyleneiminium Salts Cl₂C?NClH⁺MF₆^? and Cl₂C?NClCH₃⁺ MF₆^? (M = As, Sb) and Crystal Structure of Dichloromethyleneiminium-hyxachloroantimonate Cl₂C?NH₂⁺SbCl₆^? The N-chloro-dichloromethyleneiminium salts Cl₂C=NCIH⁺MF₆^? (M = As, Sb) are prepared by protonationof trichloromethyleneimine in the superacide system HF/MF5 at 195 K. The synthesis of the N-chloro-N-methyl-dichloromethyleneiminium salts Cl₂C?NClCH₃⁺MF₆^? (M = As, Sb) is proceeded by methylation of perchloromethylenimine by CH₃OSO⁺MF₆^? in SO₂ also at low temperature. All salts are characterized by vibrational and NMR spectra. The dichloromethyleneiminiumhexachloroantimonate crystallizes in the space group P2₁/c with a = 971.3(4)pm, b = 1134.0(4)pm, c = 2154.2(7)pm β = 102.04(3)° and Z = 8.     

Neuartige Synthese eines Lanthanoidtrialkyls – Charakterisierung und Kristallstruktur von Yb(CH2tBu)3(thf)2

Novel Synthesis of a Lanthanide Trialkyl – Characterization and Crystal Structure of Yb(CH₂ t Bu)₃(thf)₂ The solvated ytterbium alkyl Yb(CH₂tBu)₃(thf)₂ ( 1 ) was obtained in moderate yield from the reaction of ytterbium metal with neopentyl iodide. Ruby‐red air‐sensitive crystals of 1 were characterized by melting point, elemental analysis, IR, NMR, and UV/Vis spectroscopy and by X‐ray crystallography. In the solid state the ytterbium atom shows a trigonal bipyramidal coordination with the neopentyl groups and the THF ligands occupying equatorial and axial positions, respectively.     

Synthese und Kristallstrukturen von DyPt8P2 und Mg10−xPt9P7

Synthesis and Crystal Structures of DyPt₈P₂ and Mg_10?xPt₉P₇ Single crystals of DyPt₈P₂ (a = 9.260(2), b = 4.005(1), c = 9.633(2) Å, β = 102.64(3)°) were grown by heating the elements in a melt of NaCl/KCl at 1100 °C. The phosphide crystallizes in a new type of structure (I2/m; Z = 2) which consists of fragments in the shape of a cubic close packing built up by three fourths of the platinum atoms. The Dy atoms are coordinated by twelve Pt and four P atoms forming a distorted hexagonal prism which is fourfold capped by Pt atoms. Needles of Mg_10?xPt₉P₇ (a = 18.121(4), b = 23.316(5), c = 3.848(1) Å) were obtained by reaction of the elements in molten lead at 1000 °C. The main feature of the new type of structure (Pbam; Z = 4) is an oval ring of pentagonal prisms formed by each six Pt and four P atoms. The prisms are linked with each other via common faces and they are centered by Mg atoms. Another Mg atoms are located in holes of the three‐dimensional [Pt₉P₇] network. It is remarkable, that one of the ten different crystallographic sites of the Mg atoms is occupied incompletely inducing the composition Mg_10?xPt₉P₇ with x = 0.86.     

Synthese und Strukturuntersuchung von Zn3Ta2O8

Zn₃Ta₂O₈ was prepared by high temperature solid state reaction (CO₂-Lasertechnique). X-ray investigations of single crystals yield monoclinic symmetry (a=9.499;b=8.411;c=8.881 Å; =116.03°, space group C _2h ⁶ —C2/c). There is no relationship between Zn₃Ta₂O₈ and Zn₃Nb₂O₈. Zn₃Ta₂O₈ shows a characteristic structure type with octahedral coordination of Ta⁵⁺ and tetrahedral coordination of Zn²⁺.

     

Synthese und Kristallstruktur von iso‐Butylimidogalliummethyl, [CH3Ga–NCH2CH(CH3)2]6

Synthesis and X‐Ray Structure Determination of iso ‐Butylimido Galliummethyl, [CH₃Ga–NCH₂CH(CH₃)₂]₆ The thermal decomposition of [Me₂Ga–N(ⁱBu)SnMe₃]₂ (prepared by the reaction of [Me₂SnNⁱBu]₃ with GaMe₃ in a 1:3 molar ratio) in an evacuated, sealed tube at 160°C forms [MeGaNⁱBu]₆ in high yield and SnMe₄. Mass, ¹H and ¹³C NMR as well as some IR and Raman spectroscopic data are given and the crystal structure of this cage molecule with a hexagonal prismatic Ga₆N₆ skeleton has been determined.