Analyzing Ru(III)–dmso and Ru(III)–dms motifs in compounds used in the synthesis of the antimetastatic agents

The chemistry of Ru(III) complexes containing dmso as a ligand has become an interesting area in the cancer treatment field. Because of this, structural knowledge and chemistry of the moiety Ru(III)–dmso have become important to cancer research. The crystal structures of the compounds mer-[RuCl3(dms)3] (1) and mer-[RuCl3(dms)2(dmso)]:mer-[RuCl3(dms)3] (2) were determined by X-ray crystallography and a speciation of the presence of intramolecular hydrogen bond in these structures has been studied. Compound (1) crystallizes in the orthorhombic space group, Pna21; a = 16.591(8) Å, b = 8.724(2) Å, c = 10.547(3) Å; Z = 12 and (2) crystallizes in the space group, P21/C; a = 11.9930(2) Å, b = 7.9390(2)  Å, c = 15.8700(3) Å, β = 93.266(1)°, Z = 2. From the X-ray structures solved in this work, were possible to suggest an interpretation for the broad lines observed in the EPR spectra of the Ru(III) compounds explored here. Also, the exchange interactions detected by EPR spectroscopy in solid state and in solution, confirm the presence of van der Waals interactions such as C–H…Cl in the compounds (1), (2) and (3). The use of techniques such as IR, UV–vis, 1H NMR and EPR Spectroscopy and Cyclic Voltammetry were applied in this work to analyze the behavior of these metallocompounds.