Mixed-ligand cobalt(III) complexes with 1,2 cyclohexanedione dioxime (CDOH₂) as the primary ligand

Mixed-ligand cobalt(III) complexes with 1,2 cyclohexanedione dioxime as the primary ligand with substituted pyridine derivatives as secondary ligands and iodo(I-) as axial ligand have been prepared in an ethanolic medium. The complexes were characterized using infrared, UV/Vis, and conductivity measurements. The complexes are all dark brown in colour and have sharp melting points. The infrared data revealed the coordination of the cobalt(III) ion through the azomethine nitrogen (vC=N) of the CDOH₂ and the pyridine ring derivatives. The electronic spectral results gave absorption bands in the visible region assigned to ^lA_1g → ¹T_1g and ¹A_1g → ¹T_2g transiton. This is similar to that reported for low spin six coordinated cobalt(III) ions in the literature. The complexes are all nonelectrolytes in organic solvents.