Patent ID: 6518456
Filing Date: 2003-02-11
Classification: C07C

Abstract:
A process for the preparation of 1-(aminomethyl)cyclohexyl-acetic acid in pure form, which comprises the following steps:a) hydrolysis of 2-aza-spiro[4.5]decan-3-one with diluted aqueous HCl and recovery of the resulting 1-(aminomethyl)cyclohexyl-acetic acid hydrochloride by filtration and washing on the filter with acetone; b) removal of the residual hydrochloric acid from the product obtained in a) by digestion in acetone, filtration and drying; c) treatment of an aqueous solution of the product obtained in b) with bases to reach the isoelectric point (pH 7.1-7.2), filtration of the resulting 1-(aminomethyl)cyclohexyl-acetic acid and washing on the filter with aqueous ethanol; d) crystallization of 1-(aminomethyl)cyclohexyl-acetic acid obtained in c) from deionized water; or, alternatively to d) e) digestion in the hot of 1-(aminomethyl)cyclohexyl-acetic acid obtained in c) in ethanol/diisopropyl ether or methanol/diisopropyl ether and filtration in the cold.