STRUCTURE OF AN IRIDIUM BIS(PHOSPHINE)DIENE COMPLEX, A CATALYST FOR HOMOGENEOUS HYDROGENATION

(eta(4)-1,5-Cyclooctadiene)bis(triphenylphosphine)iridium(I) hexafluorophosphate, [Ir(C8H12)-(PPh3)2][PF6], C44H42F6IrP3.0.5CH2Cl2, M(r) = 1012.4, monoclinic, P2(1)/c, a = 11.666 (1), b = 18.885 (3), c = 19.492 (2) angstrom, beta = 97.07 (1)-degrees, V = 4261.7 angstrom 3, Z = 4, D(x) = 1.58 g cm-3, lambda(Mo K-alpha) = 0.71069 angstrom, mu = 33.5 cm-1, F(000) = 2012, T = 295 K, R = 0.050, wR = 0.070 for 5438 observed reflections with \F2\ > 2-sigma(F2). The geometry at iridium is approximately square planar, but the iridium-phosphorus bond lengths are significantly different: Ir-P1 2.367 (2), Ir-P2 2.326 (3) angstrom, P1-Ir-P2 = 94.3 (1), M1-Ir-P1 = 90.5, M1-Ir-M2 = 83.3, M2-Ir-P2 = 93.2-degrees (M1 and M2 are the mid-points of the C1-C2 and C5-C6 bonds).