LANTHANIDE ION-INDUCED HYDROLYZES OF ALKYL ESTERS AND AMIDES OF ALPHA-AMINO-ACIDS

Lanthanide ion-induced hydrolyses of methyl esters, ethyl esters, and amides of a-amino acids were systematically studied. In the hydrolysis of the alkyl esters, all the lanthanide ions are effective and the ca talytic activities decrease in the order Ce(III), Nd(III)>Sm(III)>Eu(I II)>Gd(III), Ce(IV)>Pr(III)>Dy(III), Tb(III), Er(III), Ho(III), Tm(III )>La(III), Lu(III), Yb(III). For the hydrolysis of the amides, however , the Ce(IV) ion is overwhelmingly more active than other lanthanide(I II) and non-lanthanide ions. The results are interpreted in terms of t he difference in the rate-limiting step for these two reactions. (C) 1 998 John Wiley & Sons, Ltd.