Multiple bonds between main group elements and transition metals, 155. (Hexamethylphosphoramide) methyl(oxo) bis(η-peroxo)rhenium(VII), the first example of an anhydrous rhenium peroxo complex: crystal structure and catalytic properties

Methyl(oxo)bis(η²-peroxo)rhenium(VII)1, the active species of the system CH₃ReO₃/H₂O₂ in the catalytic oxidation of different organic and organometallic compounds, is stabilized by a water molecule attached to the rhenium center. This water molecule can be removed and substituted by hexamethylphosphoramide (HMPA) to yield (hexamethylphosphoramide)methyl(oxo)bis(η²-peroxo rhenium(VII) (3). The synthesis, crystal structure (X-ray difraction study), and catalytic properties of which compound are reported. Crystal data are as follows: monoclinic, space group P2₁/n, A = 900.76(7) pm, B = 1229.80(11) pm, C = 1318.57(11) pm, β = 90.251(7)°, R_w = 0.034 for 1878 reflections. The catalytic properties of compound 3 in the oxidation of olefins with H₂O₂ are similar to those of 1.