Electrochemical Synthesis, X-ray Single Crystal, IR Spectroscopic, and Quantum Chemical Investigation of Molybdenum and Tungsten Hexamethoxides

The anodic oxidation of molybdenum metal in MeOH at both low anodic and cathodic current density (0.025
A/cm2) and electrolyte temperatures kept below 20 °C provides an efficient approach to Mo(OMe)6 (I). W(OMe)6
(II) can be obtained from the electrolytes, prepared via anodic dissolution of tungsten, by fractional crystallization.
The symmetrically independent units in the structures of I and II, being isomorphous, follow the C1 (slightly
distorted D2d) symmetry. Theoretical calculations performed for a free molecule of I indicate that this low symmetry
may be the result of the packing of the molecules in the crystal structure and also an inherent property imposed
by the bonding in this compound. Crystal data for I:  Mo(OMe)6 at 22 °C, a = 7.0976(13), b = 6.6103(12), and
c = 12.286(2) Å, β = 90.068(3)°, V = 576.41(18) Å3, monoclinic P2/n, Z = 2. Crystal data for II:  W(OMe)6
at 22 °C, a = 7.1164(19), b = 6.6414(18), and c = 12.304(3) Å, β = 90.047(5)°, V = 581.5(3) Å3, monoclinic
P2/n, Z = 2.