T. Rübenstahl

Die Kristallstrukturen der silylierten Phosphanimine Me3SiNPPh3 und Me3SiNPPh2 - C2H4 - PPh2NSiMe3 / Crystal Structures of the Silylated Phosphanimines Me3SiNPPh3 und Me3SiNPPh2 - C2H4 - PPh2NSiMe3

The crystal structures of two silylated phosphanimines have been determined. Me3SiNPPh3: Space group P 1̃, Z = 2, structure refinement with 2907 observed unique reflections with Fo > 5 σ(Fo), R = 0.052. Lattice dimensions at 19 °C: a = 876.6(1), b = 1125.8(1), c = 1151.2(1) pm, α = 61.71(1)°, β = 88.08(1)°, γ = 87.18(1)°. The compound forms monomeric molecules with a SiNP bond angle of 140.2° and bond lengths PN of 154.2 pm and SiN of 168.6 pm which correspond with PN double and SiN single bonds. Me3SiNPPh2 - C2H4 -PPh2N SiMe3: Space group P31, Z = 3, structure refinement with 4251 independent reflections, R = 0.061 for 3587 reflections with I > 2σ(I). Lattice dimensions at - 80 °C: a = b = 1591.4(1), c = 1165.8(1) pm. The compound forms monomeric molecules with a c/s-conformation of the PNSiMe3 groups. Bond angles and bond lengths (average) are SiNP = 140.8°, PN = 153.8 pm, SiN = 165.6 pm.

Die isoelektronischen Molekülkomplexe TiCl3(NPPh3) und TiCl3(OSiPh3) / The Isoelectronic Molecular Complexes TiCl3(NPPh3) and TiCl3(OSiPh3)

Abstract TiCl3(NPPh3) and TiCl3(OSiPh3) have been prepared from titanium tetrachloride and Me3SiNPPh3 and HOSiPh3, respectively. Both complexes were characterized by IR spectroscopy and by crystal structure determinations. TiCl3(NPPh3): Space group R3̄̅, Z = 6, structure analysis with 959 observed unique reflections, R = 0.039. Lattice dimensions at -68°C: a = b = 1370.5(7), c = 1845.9(9) pm. TiCl3(OSiPh3): Space group P21/c, Z = 8, structure analysis with 4549 observed unique reflections, R = 0.049. Lattice dimensions at 19°C: a = 2127.7(2), b = 947.2(1), c = 2136.8(1) pm, β = 105.081(5)°. Both complexes form monomeric molecules in which the titanium atom is tetrahedrally coordinated by three chlorine atoms, the nitrogen atom of the phosphorone iminato ligand and the oxygen atom of the silyloxy group, respectively. The bond lengths TiN of 171.9(4) pm and TiO of 171.0(3) (in average) correspond to double bonds.