Patent ID: 7612237

Claim:
A process for preparing enantiomerically enriched compounds of general formula (I) in which R 1 , R 2 , R 3 , R 4 , R 5 are each independently (C 1 -C 8 )-alkyl, HO—(C 1 -C 8 )-alkyl, (C 2 -C 8 )-alkoxyalkyl, (C 6 -C 18 )-aryl, (C 7 - 19 )-aralkyl, (C 3 -C 18 )-heteroaryl, (C 4 -C 19 )-heteroaralkyl, (C 1 -C 8 )-alkyl-(C 6 -C 18 )-aryl, (C 1 -C 8 )-alkyl-(C 3 -C 18 )-heteroaryl, (C 3 -C 8 )-cycloalkyl, (C 1 -C 8 )-alkyl-(C 3 -C 8 )-cycloalkyl, (C 3 -C 8 )-cycloalkyl-(C 1 -C 8 )-alkyl, or R 4 and R 5 and/or R 2 and R 3 together form a (C 2 -C 8 )-alkylene bridge, where R 1 , R 2 , R 3 , R 4 may additionally be H and with the proviso that R 1 is not phenyl when R 4 and/or R 5 =H, said process comprising: a) reacting epoxycarboxamides of general formula (II) in which R 1 , R 4 , R 5 are each as defined above, with ammonia or amines of the general formula (III) in which R 2 , R 3 are each as defined above; wherein enantiomerically enriched compounds of general formula (I) are prepared using enantiomerically enriched compounds of formula (II); or as a second step b) enantioselectively crystallizing the salts of racemic diastereomerically enriched compounds of formula (I) using a chiral organic acid; and wherein one or more of the following conditions apply: i) R 1 is a (C 1 -C 8 )-alkyl; ii) R 4 is H; iii) R 5 is a (C 1 -C 8 )-alkyl-(C 3 -C 8 )-cycloalkyl; iv) R 5 is cyclopropyl.