Crystal structure of di-µ-carbonyl-heptacarbonyltris[(dimethyl)phenylphosphine]-triangulo-tri-iron, [Fe3(CO)9(PMe2Ph)3]

Abstract

Crystals of [Fe₃(CO)₉(PMe₂Ph)₃] are orthorhombic, space group Pbca, with a= 16·76, b= 18·75, c= 23·43 Å, Z= 8. The structure was refined by least-squares with isotropic temperature factors to a final R of 11·4% for 1394 independent reflections. The molecule retains the skeleton of Fe₃(CO)₁₂, the isosceles triangle of iron atoms having its shortest (2·540 Å) side bridged by two carbonyl groups whilst the two longer (2·688 Å) sides are unbridged. The three phosphine molecules, one attached to each iron atom, occupy co-ordination positions which place all three phosphorus atoms coplanar with the triangle of iron atoms.