Process for the preparation of trans 4-amino-cyclohexyl acetic acid ethyl ester HCl

摘要

The invention relates to a process for the preparation of trans 4-amino-cyclohexil ethyl acetate HCl wherein d) hydrogenating 4-nitrophenyl acetic acid in a protic solvent at a temperature between 40-500C in the presence of Pd/C under 0.1-0.6 bar overpressure, and e) further hydrogenating the 4-aminophenyl acetic acid obtained in situ in step a) at a temperature between 50-60 0C under 1-4 bar overpressures, then f) heating to reflux the 4-aminocyclohexil acetic acid obtained in step b) for 1-3 hours in hydrochloric ethanol, and if desired after removing the solvent acetonitrile was added to the residue obtained and distilled off.