Phosphaniminato-Komplexe des Iods. Synthese und Kristallstrukturen von Ph3PNIO2 und Ph3PNSiMe3 · I2

Phosphoraneiminato Complexes of Iodine. Syntheses and Crystal Structures of Ph₃PNIO₂ and Ph₃PNSiMe₃ · I₂ Ph₃PNIO₂ has been prepared as yellow crystals by the reaction of Ph₃PNSiMe₃ with I₂O₅ in boiling acetonitrile, whereas the molecular complex Ph₃PNSiMe₃ · I₂ is formed as brown crystals by the reaction of Ph₃PNSiMe₃ with iodine in acetonitrile solution. Both complexes were characterized by crystal structure determinations. Ph₃PNIO₂: Space group P2₁/n, Z = 4, 2 858 observed unique reflections, R = 0.039. Lattice dimensions at 19°C: a = 972.8(2), b = 1 743.4(3), c = 1 073.7(2) pm, β = 115.46(3)°. The compound forms monomeric molecules with pyramidal geometry at the iodine atom. The bond angle PNI (126.9°) is unusually small; the PN bond length of 159.2 pm corresponds with a double bond. Ph₃PNSiMe₃ · I₂: Space group P1 , Z = 2, 3 560 observed unique reflections, R = 0.033. Lattice dimensions at 19°C: a = 941.2(2), b = 1 041.7(2), c = 1 287.4(3) pm, α = 78.34(1)°, β = 72.00(2)°, γ = 86.08(2)°. The compound forms monomeric molecules, in which the I₂ molecule and the nitrogen atom of the phosphoraneimine molecule realize a linear N? I? I axis with a bond length N? I of 243.2 pm.