The synthesis of the salt [(tpm)Ru(H2O)3(p-CH3C6H4SO3)2l.5H2O, where tpm is the terdentate facial ligand tris(l-pyrazolyl)methane, is described. The salt was prepared as a possible precursor to a structurally stabilized but reactive cis-di-oxoruthenium(VI) oxidant. The crystal structure of the salt has been determined from three-dimensional X-ray data. It crystallizes in the triclinic space group P1 with two formula units in a cell of dimensions α = 10.780 (5) Å, b = 11.122 (8) Å, c = 14.489 (4) Å, α = 74.60 (5)°, β = 67.23 (4)°, and γ = 87.41 (5)°. The structure has been refined to a final value of R = 0.031 based on the intensities of 3390 reflections. The crystal structure proves that the complex is the fac isomer in which the terdentate ligand occupies three sites on one face of the coordination octahedron and the three water molecules occupy the opposite face. Electrochemical studies at activated glassy-carbon electrodes show the appearance of waves for Ru(III/II), Ru(IV/III), and Ru(V/IV) couples. Oxidation past Ru(IV) leads to an opening of one of the chelating arms of the tpm ligand and formation of a trans-dioxo complex of Ru(VI). © 1990, American Chemical Society. All rights reserved.
|Publication status||Published - 1 Jan 1990|