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]

Abstract

The reaction of the ligand dimethylglyoxime (dmg-H₂) with <i>cis</i>-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] (<strong>1</strong>) and [RuCI(dmg-H₂)₂(DMSO)]Cl (<strong>2</strong>). These two complexes have been separated by column chromatography and characterized. The molecular structure of [RuCl₂ (dmg- H₂)(DMSO)₂ (<strong>1</strong>) 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] (<strong>3</strong>). The geometry of these complexes (<strong>1-3</strong>) has been established on the basis of IR, ¹H and ¹³C {¹H} NMR spectral data.