PROCESS FOR THE PREPARATION OF OPTICALLY ACTIVE PIPERAZINE-2-CARBOXYLIC ACID DERIVATIVES

摘要

Optically active piperazine-2-carboxylic acid derivatives of the general formula: <IMG> wherein R1 and R X is hydroxyl alkoxy or a (substituted) amino group, are prepared by asymmetric hydrogenation of the corresponding 1,4,5,6-tetrahydropyrazines, catalyzed by optically active rhodium, ruthenium or iridium complexes. The compounds of the formula I are intermediates for the preparation of pharmaceutically active ingredients, for example HIV protease inhibitors.