Phosphine (PH3) complexes of ruthenium, osmium and iridium as precursors of terminal phosphido (PH2) complexes and the crystal structure of 2-PH2)Cl(CO)(PPh3)2>2.(C2H2Cl4)4

Article abstract of DOI:10.1016/0022-328X(88)80421-2

Stable phosphine complexes MHCl(PH3)(CO)(PPh3)2 (M = Os, 1a, M = Ru, 1b) and IrHXCl(PH3)(PPh3)2 (X = H, 2, X = Cl, 3) have been prepared by substitution of phosphine for a labile triphenylphosphine in tris(triphenylphosphine) precursors.Strong acids (e.g. aqueous HClO4 in CH3CN) cleave the hydride-metal bonds in 1a, 1b to give ClO4 (9a, 9b) as a mixture of isomeric complexes.The ligands Cl^-, PMe3, and CO can be substituted for the labile acetonitrile in 9a to give OsCl2(PH3)(CO)2(PPh3)2 (12) ClO4 (10) and ClO4 (11), respectively.Base deprotonates 10 and 11 to give stable isolable terminal phosphido complexes OsCl(PH2)L(CO)(PPh3)2 (L = CO, 14, L = PMe3, 15), but when 9a is deprotonated, acetonitrile is also lost and a dimeric complex 2-PH2)Cl(CO)(PPh3)2>2 (13) is formed.The colourless crystals of 13 are triclinic with space group P1, a 14.101(4), b 15.091(5), c 11.708(5) Angstroem, α 96.68(3), β 91.71(3), γ 63.92(2) deg, Z = 1, V = 2222.0 Angstroem³.The final refinement gave R = 0.0589, R_w = 0.0603 for 4865 observed reflections.Phosphine oxidatively adds to Os(CO)2(PPh2)3 to give the stable hydride-phosphido-complex, OsH(PH2)(CO)2(PPh3)2 (19).