THE SYNTHESES AND CRYSTAL-STRUCTURES OF CIS-[BIS(DIPHENYLPHOSPHINO)METHANE][1,2-BIS(DIPHENYLPHOSPHINO)ETHANE]DICARBONYLMOLYBDENUM(0) AND CIS-[1,2-BIS(DIPHENYLPHOSPHINO)ETHANE][CIS-1,2-BIS(DIPHENYLPHOSPHINO)ETHYLENE]DICARBONYLMOLYBDENUM(0)

The title compounds, Mo(CO)2(Ph2PCH2PPh2)(Ph2PCH2CH2PPh2), Mo(CO)2(dppm)(dppe) 1, and Mo(CO)2(Ph2PCH2CH2PPh2)(Ph2PCH = CHPPh2), Mo(CO)2(dppe)(cis-vpp) 2, were prepared from Mo(CO)6 and the corresponding bidentate diphosphine ligands in n-decane under nitrogen atmosphere. Crystals of 1 are monoclinic, space group P2(1)/c, with a = 19.072(3), b = 11.348(3), c = 23.57(1) angstrom, beta = 99.64(3)-degrees, Z = 4, and the final residual R(F) = 0.044 for 4810 observed reflections; data of 2 are triclinic, space group P 1, with a = 12.091(3), b = 12.186(8), c = 18.934(5) angstrom, alpha = 96.93(4), beta = 108.15(2), gamma = 107.08(4)-degrees, Z = 2, and the final residual R(F) = 0.058 for 4570 observed reflections. The distortion of compound 1 is more pronounced than that of compound 2. The two Mo-P lengths in the same bidentate chelate ligand for both compounds are different. Among them, the two larger Mo-P bond lengths for compound 2 are similar, but significantly different for 1.