Different binding modes of dimethylglyoxime (dmg-H₂) towards Ru(II) ion: Synthesis and structural characterization of [Ru^IICl₂( dmg-H₂)(DMSO)₂] and synthesis of [Ru^IICl(dmg-H₂)₂(DMSO)]Cl and [Ru^II(dmg-H)₂(DMSO)₂]

17-22The reaction of the ligand dimethylglyoxime (dmg-H2) with cis-RuCI2(DMSO)4 in 2:1 molar ratio in dichlorornethane-methanol mixture results in the formation of a mixture of two complexes of compositions, [RuCl2(dmg-H2)(DMSO)2] (1) and [RuCI(dmg-H2)2(DMSO)]Cl (2). These two complexes have been separated by column chromatography and characterized. The molecular structure of [RuCl2 (dmg- H2)(DMSO)2 (1) has been established by single crystal X-ray study. When the same reaction is conducted in DMF at 100° the ligand deprotonates with the formation of another complex, [Ru(dmg-H)2(DMSO)2] (3). The geometry of these complexes (1-3) has been established on the basis of IR, 1H and 13C {1H} NMR spectral data