Preparation and spectral characterization of some mixed-ligand cobalt(III) complexes of the form [Co(L-pyala)(A)], a = L-histidinate, L- or D-aspartate, or iminodiacetate

Article abstract of DOI:10.1021/ic50206a048

Mixed-ligand cobalt(III) complexes of the form [Co(L-Pyala)(A)], where A = L-histidinate, L- or D-aspartate, or iminodiacetate and L-Pyala^- = L-H₂NCH(CH₂C₅H₄N)CO₂ ^-, were prepared from Co(III) and Co(II) reactants. Isolated isomers of each complex were assigned structures on the basis of their visible and circular dichroism spectra. The observed distribution of isomers suggests that in these complexes, as well as in previously reported Co(Pyala)₂⁺ complexes, amino groups avoid being trans to each other; pyridyl groups also avoid being trans to each other but prefer to be trans to an amino group.