Preparation and crystal and molecular structure of [MoO(SCH2CH2PPh2)2]

Abstract

The title complex has been prepared by reaction of [MoO₂(acac)₂](acac = pentane-2,4-dionate) with an excess of Ph₂PCH₂CH₂SH in methanol or toluene. The oxo-group can be protonated with anhydrous HBF₄ in benzene to give [Mo(OH₂)(SCH₂CH₂PPh₂)₂][BF₄]₂ but does not undergo condensation-type reactions with hydrazines even under forcing conditions. The complex [MoO(SCH₂CH₂PPh₂)₂] crystallises in the orthorhombic space group P2₁2₁2₁ with four molecules in a unit cell of dimensions a= 10.263(3), b= 10.246(1), and c= 26.657(5)Å. The structure has been solved using 2 179 symmetry-independent reflections with I > 2.58σ(I) collected by counter techniques using Cu-K_α radiation. Refinement by full-matrix least squares, using anisotropic temperature factors for all non-carbon and non-hydrogen atoms, gives a final R factor of 0.063. The co-ordination polyhedron is intermediate between trigonal-bipyramidal and square-pyramidal geometries. The bond distances to Mo are Mo–O 1.733(9), Mo–S(av.) 2.360(4), and Mo–P(av.) 2.484(4)Å.