Preparation and characterization of cobalt(III) complexes with sarcosine and some tetradentate ligands of the edda type

Meridional geometrical isomers of cobalt(III) complexes with sarcosine (N-methylglycine) and tetradentate ligands edda (ethylenediamine-N, N ' -diacetate ion), eddp (ethylenediamine-N, N ' -di-3-propionate ion) and 1,3-pdda (1, 3-propylenediamine-N,N ' -diacetate ion) have been prepared. The edda and eddp cobalt(III) complexes were made by the reaction of sarcosine and sodium ethylenediamine-N, N ' -diacetato(carbonato)cobaltate(III), and sodium uns-cis-(ethylenediamine-N,, N ' -di-3-propionato)(carbonato)cobaltate(III) dihydrate, respectively. The previously synthesized pdda-cobalt(III) complex with sarcosine was obtained by a new route by direct synthesis of cobalt(II) chloride hexahydrate with sarcosine and 1,3-pdda in the presents of lead(IV) oxide. Complexes were isolated chromatographically and characterized by elemental analysis, electron absorption spectra, infrared spectra and H-1 NMR spectroscopy.