Cyclopentadienyl-ruthenium and osmium chemistry. XL X-ray crystal structures of MBr(PPh₃)₂(η-C₅H₅).CH₂CI₂(M = Ru, Os)

Abstract

<jats:p>The crystal and molecular structures of MBr (PPh3)2(η-C5H5).CH2Cl2 (M = Ru and Os) have been determined. A revised synthesis of the bromo osmium complex is given. The coordination geometry about the metal atom is based on a distorted octahedron with one face being occupied by the cyclopentadienyl group [average Ru -C(Cp) 2.214(3), Os-C(Cp) 2.177(3)Ǻ] and the other by the bromide [ Ru -Br 2.5683(8), Os-Br 2.5438(9)Ǻ] and the two phosphorus atoms [ Ru -P 2.323(2), 2.329(1); Os-P 2.290(2), 2.297(2)Ǻ]. Structural parameters are compared with those of the corresponding chloro complexes and differ only minimally. Crystals of MBr (PPh3)2(η-C5H5).CH2Cl2 are triclinic, space group Pī , with unit cell dimensions ( Ru [Os]): a 14.374(5) [14.276(4)], b 14.057(4) [13.959(3)], c 10.012(5) [9.903(3)]Ǻ, α 99.43(3) [99.79(2)], β 105.60(3) [105.74(2)], γ 100.42(3) [100.39(2)]°, V 1868(1) [1817.7(9)] Ǻ3, Z 2. The structures were refined by a full-matrix least-squares procedure to R 0.050 [0.036] for 7365 [5108] reflections with I ≥ 3σ(I).</jats:p>