CARBON-13 AND PROTON MAGNETIC RESONANCE AND CIRCULAR DICHROISM STUDIES OF VARIOUS COMPLEXES OF COBALT(III) WITH ETHYLENEDIAMINE-N, N′-DIACETATE-N, N′-DI-3-PROPIONATE

Abstract

Two nitro, two aqua and a dinitro complex of ethylenediamine-N-N′-diacetato-N,N′-di-3-propionatocobaltate have been isolated. The four quinquedentate complexes have been resolved optically and their electronic absorption and CD spectra measured. Pmr spectra at 250 MHz have also been measured for the quinquedentate complexes as well as for the dinitro complex. Those of the quinquedentate complexes are quite complicated and difficult to interpret. ¹³C magnetic resonance spectra have been measured for all of these complexes and also for the sexidentate, trans(O₅) and trans(O₅O₆) isomers of [Co(EDDDA)]⁻. The ¹³C spectra are much less complex and indicate that this technique can be useful as a tool for the study of stereochemistry of metal complexes with ligands containing several carbon atoms.