Reaction of MoOCl3 with Me3SiN3 m THF followed by addition of tertiary phosphine oxides, RPO3(R3=Ph3, Ph2Et, Ph2Me), gives [MoCl2(NH)O(OPR3)2]. The crystal and molecular structure of the compound has been determined by x-ray diffraction methods. The complex crystallises in the monoclinic space group P21 /a with four molecules in a unit cell having dimensions a=15.667(8) Å, b=20.135(9) Å, c=9.726(7) Å and β=95.01(1) Å. A total of 3510 reflections were collected by counter techniques using MoKα radiation. The structure was refined on 2597 reflections with I > 2.58 σ (I) by full matrix least squares, using anisotropic temperature factors for all nonhydrogen atoms, to give a final R factor of 0.082. The overall configuration of the distorted octahedral complex is trans-dichloro-cis-bis[ethyl(diphenyl)phosphineoxide]cis-(oxo) imido with the molybdenum formally in the oxidation state (VI). The imido hydrogen has been located, and the Mo-N-H system is nonlinear. © 1979 Verlag Chemie, GmbH.
