Abstract: Thin-layer chromatography is employed to separate enantiomers of the general formula, ##STR1## in which C* represents an asymmetric center and the substituents R.sup.1, R.sup.2, and R.sup.3 are such that they supply the structural element ##STR2## for .alpha.-amino- or .alpha.-iminocarboxylic acids, particularly the well-known .alpha.-amino- or .alpha.-iminocarboxylic or for derivatives of such carboxylic acids, either of which contains no free thiol groups. In the thin-layer chromatographic separation operation a TLC plate is used which is coated with silica gel hydrophobicized by a silane derivative and which is further impregnated with an ionic compound of a divalent transition metal and a chiral selector. The mobile phase employed is a ternary mixture of a water-miscible alkanol, such as methanol, water, and acetonitrile, or a quaternary mixture of the latter ternary mixture to which a water-miscible cyclic ether, such as tetrahydrofuran, has been added.