95482-46-5Relevant academic research and scientific papers
Syntheses and molecular structures of Os2X2(PhCONH)4 (X = Cl, Br) compounds
Chakravarty, Akhil R.,Cotton, F. Albert,Tocher, Derek A.
, p. 1334 - 1338 (2008/10/08)
The compound Os2Cl2(PhCONH)4 (1) was prepared by reacting Os2Cl2(O2CCH3)4 with benzamide at 140°C. The dibromo analogue (2) was obtained by adding a tetraalkyl bromide salt to a solution of 1 in Me2SO. Both compounds are dark green in color, soluble in Me2SO, but only sparingly soluble or insoluble in other common organic solvents. Both compounds are indefinitely stable in air. The molecular structures of both the compounds, which are isomorphous, were obtained by X-ray crystallography. They crystallize in the triclinic space group P1 with 2 molecules per unit cell. The molecules have a center of inversion, and thus the asymmetric unit consists of half of each of two dinulcear molecules at 0, 0, 0 and 1/2, 1/2, 1/2. The unit cell dimensions are as follows: Os2Cl2(PhCONH)4, a = 10.840 (6) A?, b = 14.381 (7) A?, c = 10.682 (7) A?, α = 110.91 (4)°, β = 105.80 (6)°, γ = 68.10 (6)°, V = 1424 (1) A?3; Os2Br2(PhCONH)4, a = 10.918 (7) A?, b = 14.663 (6) A?, c = 10.497 (8) A?, α = 108.18 (3)°, β = 106.13 (7)°, γ = 68.65 (6)°, V = 1461 (1) A?3. The structures of 1 and 2 were refined to R = 0.074 (Rw - 0.083) and R = 0.074 (Rw = 0.086), respectively. The mean Os≡Os distances in 1 and 2 are 2.367 [2] and 2.384 [2] A?, respectively. The mean Os-Cl and Os-Br distances are 2.490 [9] and 2.611 [5] A?, respectively. The electronic spectra of these compounds show low-energy bands at 762 and 643 nm in CH2Cl2. Os2Cl2(PhCONH)4 has a magnetic moment of 1.76 μB at 25°C and undergoes one-electron reduction at -0.07 V vs. SCE in Me2SO.
