Cobalt(III) complexes of a conjugated tetradentate ligand and their interaction with imidazole

Abstract

The reaction of 2,3-butanedionemonoxime with 1,2-diaminobenzene results in the formation of a neutral conjugated tetradentate ligand, 3,8-dimethyl-5,6-benzo-4, 7-diazadeca-3,7-diene-2,9-dione dioxime (H₂Me₂bzo), which reacts with CoX₂ (X = Cl, Br, I, SCN, SeCN) to form [Co(HMe₂bzo)X₂]<em>. </em>This complex in turn reacts with imidazole to form [Co(HMe₂bzo)(Im)(X)] (I). On the other hand, direct interaction of CoX₂ H₂Me₂bzo and imidazole results in the formation of [Co(Me₂bzo)(Im)₂]X (II) (X =Cl, Hr, I, SCN, SeCN, NO₃, ClO₄). All compounds are diamagnetic and are characterised by electronic, IR, ¹H and ¹³C NMR spectra.