Synthesis, characterization, DNA binding and cleavage studies of Ru(II) complexes containing oxime ligands

The Ru(II) precursors, [RuHCl(CO)(EPh₃)₃] (E = P or As) when reacted with some well known monoxime and dioxime ligands in ethanolic solution afforded the new complexes of the types [RuCl(CO)(EPh₃) ₂L1], [RuH(CO)(EPh₃)₂L2] and [RuCl(CO)(EPh ₃)₂L3] ((H₁L1) = diacetylmonoxime, (H ₁L2) = dimethylglyoxime and (H₂L3) = benzoiloxime). The ligands coordinated in a bidentate chelate mode forming a five membered chelate ring. The molecular structures of two of the complexes have been determined by single crystal X-ray diffraction study. The structural determination confirms the deprotonation of the oxime function. Examination of all the complexes by cyclic voltammetry showed the occurrence of some quasi-reversible redox reactions owing to changes in the oxidation state of the central metal atoms. Structural assignments are supported by combination of IR, UV-Vis, ¹H NMR and elemental analyses. In addition, the DNA binding properties and cleavage efficiency of new complexes have been tested.