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 descri bed. These ligands, after complexation with EuCl3.6H(2)O, are highly s uitable as chiral shift reagents for the enantiomeric excess determina tion of amino acids and alpha-alkylated amino acids in aqueous solutio ns. Resolution experiments using various amino acids and their derivat ives and a study of the pH dependency of the induced diastereomeric sh ift differences are included.