Identification and characterization of the trans(O 5) and trans(O 5O 6) isomers of hexadentate rhodium(III) complex of 1,3-propanediamine- N,N′-diacetic- N,N′-di-3-propionic acid

Abstract

Rhodium(III) complexes with the hexadentate ligand, 1,3-propanediamine- N,N′-diacetate- N,N′-di-3-propionate ion (1,3-pddadp) have been prepared, chromatographically separated and isolated into two geometrical isomers with respect to the NO chelate ring size ( trans(O 5) and trans(O 5O 6)). The 1H and 13C NMR and electronic absorption spectra were used to characterize the Rh(III) complexes. The 13C NMR spectra for two isomers of the corresponding [Co(1,3-pddadp)] - complex of known geometry ( trans(O 5O 6) and trans(O 6)) are also reported. The related edta-type complexes of known structure were used as references for assignment of complexes studied.