Synthesis and spectral characterization of cobalt(III) complexes of N-(o-carboxyphenyl)iminodiacetic acid

Abstract

The complexes [Co(cpida)(N–N)]·nH₂O [H₃cpida =N-(o-carboxyphenyl)iminodiacetic acid, N–N = ethylenediamine, 1,2-diaminopropane, or 1,3-diaminopropane] have been synthesized from trans-[Co(N–N)₂Cl₂]⁺ as well as by direct oxidation procedures. The dinitro complex Na₂[Co(cpida)(NO₂)₂] has been synthesized from Na₃[Co(NO₂)₄(CO₃)]. They have been characterized by u.v.–visible, i.r., and ¹H n.m.r. spectroscopy. The amine spectral pattern and the acetate splitting in the ¹H n.m.r. offers valuable information about the geometry of the ligand around the metal ion.