Isolation,reactions and x-ray structure of tetraethylammonium dihydridotetracarbonylrhenate

The isolation and characterization of the novel hydridic compound [Net₄][H₂Re(CO)₄], obtained from the reaction of Re₂(CO)₁₀ with methanolic KOH, are described. Its reactions with I₂, strong acids, and ethanol are reported. The salt gives triclinic crystals, investigated by X-ray analysis, with cell constants a = 14.493(6), b = 7.564(3), c = 7.930(3) Å, α = 72.97(4)°, β = 81,73(4)°, γ = 96.63(4)°; space group P$\text{1}$. The structure was solved by conventional Patterson and Fourier methods and refined by least-squares up to a final R values of 0.071, for 1586 independent counter data. The anion exhibits a distorted octahedral geometry, with the two hydrido ligands in cis position between themselves. The mean values of the ReC and CO distances are 1.89 and 1.21 Å. The carbonyl groups are significantly bent towards the hydrido ligands.