THE PREPARATION AND CHARACTERISATION OF SALTS OF cis-BIS(2,2′-BIPYRIDINE)-CHLORO(DIMETHYLSULFOXIDE)-RUTHENIUM(II) AND THE CRYSTAL STRUCTURE OF THE PERCHLORATE DIHYDRATE. PRECURSORS FOR DNA-BINDING RUTHENIUM(II) COMPLEXES

The preparation and characterisation of salts of the complex cation cis-bis(2,2′-bipyridine)-chloro(dimethylsulfoxide-S)ruthenium(IIII), [Ru(bpy)2Cl(dmso)]+, is reported. The complex was prepared by the reaction of 2,2′-bipyridine with RuCl3 · 3H2O in dimethylsulfoxide. The value of this complex arises from its ability to react with suitable bidentate ligands particularly those that could act as DNA intercalators. The structure of [Ru(bpy)2Cl(dmso)][ClO4] · 2H2O has been determined by single crystal X-ray diffraction. The complex crystallises in space group PI with a = 8.205(3), b = 10.448(4), c = 16.769(6) Å; α = 78.99(3)°, γ = 77.47(3)°, γ = 72.20(3)°, Z=2. The structure was refined by least-squares methods using 4070 observed reflections with 196 variable parameters (final R = 0.039).