Cluster chemistry LV. Stereochemistry of group 15 ligand-substituted derivatives of M3(CO)12 (M = Ru, Os). A. X-Ray structures of six complexes M3(CO)11(L) (M = Ru, L = PPh(OMe)2, P(OCH2CF3)3, P(OCH2)3CEt and AsPh3; M = Os, L = PPh3 and PPh(OMe)2)

Article abstract of DOI:10.1016/0022-328X(88)80280-8

X-ray crystal structures of six complexes M3(CO)11(L) (M = Ru, L = PPh(OMe)2, P(OCH2CF3)3, P(OCH2)3CEt and AsPh3; M = Os, L = PPh3 and PPh(OMe)2) have been determined.Consideration of these results, together with other published data, allowed several conclusions to be drawn concerning the effect of substituting one CO group in M3(CO)12 (M = Ru, Os) by a P- or As-donor ligand.The most important are that L occupies an equatorial site, the M-M separation cis to L increases with increasing cone angle of L, while the CO_eq ligand cis to L on the same metal atom is more tightly bound.Distortions of the M3L12 molecule from D_3h to D3 geometry appear to be related to the ?-donor properties of L.The reactions between Ru3(CO)12 and P(OCH2CF3)3, and between Os3(CO)12 and PPh3 or PPh(OMe)2, to give M3(CO)_12-n(L)_n (n = 1-3), are described.Crystal data: Ru3(CO)11, monoclinic, P2₁/c, a 9.647(3), b 20.529(7), c 14.692(5) Angstroem, β 119.93(2) deg, U 2522(1) Angstroem³, Z = 4, N₀ (observed data, with I>3?(I)) = 5829, R = 0.035, R' = 0.037; Ru3(CO)11, triclinic, P1, a 12.920(1), b 11.530(2), c 10.189(1) Angstroem, α 85.93(1), β 86.57(1), γ 70.66(1) deg, U 1427(1) Angstroem³, Z = 2, N₀ = 4061, R = 0.038, R' = 0.054; Ru3(CO)11, monoclinic, P2₁/c, a 13.57(1), b 14.779(1), c 12.362(3) Angstroem, β 98.34(4) deg, U 2453(1) Angstroem³, Z = 4, N_o= 5950, R = 0.039, R' = 0.054; Ru3(CO)11(AsPh3), monoclinic, C2/c, a 22.496(6), b 16.348(4), c 17.345(5) Angstroem, β 103.65(2) deg, U 6198(3) Angstroem³, Z = 8, N_o= 6071, R = 0.032, R' = 0.028; Os3(CO011(PPh3), monoclinic, C2/c, a 22.196(5), b 16.265(3), c 17.370(5) Angstroem, β 103.86(2) deg, U 6088(33) Angstroem³, Z = 8, N_o= 4125, R = 0.031, R' = 0.033; Os3(CO)11, monoclinic, P2₁/c, a 10.817(3), b 14.993(4), c 16.174(3) Angstroem, β 101.87(2) deg, U 2567(1) Angstroem, Z = 4, N_o = 5506, R = 0.047, R' = 0.057.