ASYMMETRIC-SYNTHESIS OF NEW CHIRAL EUROPIUM N,N'-DISUCCINATE COMPLEXES - SHIFT-REAGENTS FOR AQUEOUS-SOLUTIONS AND APPLICATION IN THE ENANTIOMERIC EXCESS DETERMINATION OF AMINO-ACIDS

The synthesis of new chiral N,N'-disuccinate ligands (R,R)-8, (R,R)-9, and (S,S)-10 from (5R)- or (SS)-(menthyloxy)-2(5H)-furanone is described. These ligands, after complexation with EuCl3.6H(2)O, are highly suitable as chiral shift reagents for the enantiomeric excess determination of amino acids and alpha-alkylated amino acids in aqueous solutions. Resolution experiments using various amino acids and their derivatives and a study of the pH dependency of the induced diastereomeric shift differences are included.