Optical Inversion of the cis(NO2), trans(N), cis(O)- bis(Aminocarboxylato)dinitroco baltate(III)Ion

Institute of Chemistry, Faculty of Sciences, University of Beograd, P.O. Box 550, 11001 Beograd, Yugoslavia

The inversion kinetics of optical isomers of $cis$(NO₂), trans(N), $cis$(O)-dinitrobis (aminocarboxylato)cobaltate(III) ions, containing various $\propto$- and $\beta$-amino acid residues (glycine, S- aminobutyric acid, S-lencine and $\beta$-alanine) have been studied. The inversion process was followed polarimetrically in sodium nitrate solution, between 55 and 95^°(1- 0.15). It was established that the inversion of the $cis$(NO₂), $trans$(N), $cis$(O) optical isomer of the dinitro $bis$($\beta$-alaninato)cobaltate(III) ion. in which alanine forms six-membered aminocarboxylato ligand rings. In addition, it was assumed that the $cis$-(NO₂), $trans$(N), $cis$(O) optical isomers of dinitrohis(aminocarboxylato)cobaltate(III) complexes containing $\propto$- and $\beta$ aminocarboxylato residues, respectively, rearrange via an intramolecular mechanism which involves the bond rupture between one end of the amino­carboxylato ligand and the central ion.