Some cyclic tetra-amine complexes of cobalt

Abstract

The synthesis of the three isomeric forms of the cyclic tetra-amine 5,12-dimethyl-7, 14-diphenyl-1,4,8,11-tetra-azacyclotetradecane (ø2teta, ø2tetb and ø2tetc), and some of their respective cobalt (III) complexes are described. Electronic, infra-red and proton magnetic resonance spectra of these complexes are reported. Properties of the cobalt (III) derivatives of ø2teta and ø2tetc indicate that these compounds are trans disubstituted octahedral with the macrocycle in planar tetra-dentate coordination, while properties of cobalt (III) derivatives of ø2tetb are indicative of a cis disubstituted octahedral structure with the macro-cycle in folded coordination. The possible isomeric forms of the macrocyclic ligands due to restricted inversion about the asymmetric secondary amine groups are also discussed.