Patent ID: 8809581
Filing Date: 2014-08-19
Classification: C07C

Abstract:
1. A method of making 6-aminocaproic acid as an active pharmaceutical ingredient, consisting essentially of: performing a hydrolysis procedure to have ε-caprolactam react with sodium hydroxide or potassium hydroxide to generate a first reaction mixture and then subsequently performing a modification procedure to have a solubility regulating agent react with the first reaction mixture to form a second reaction mixture including aqueous inorganic salt and aminocaproic acid intermediate; performing a separation procedure to have the intermediate separated from the second reaction mixture to use an organic solvent to extract the aminocaproic acid intermediate from the second reaction mixture by having the aminocaproic acid intermediate dissolve in the organic solvent to isolate the aminocaproic acid intermediate from aqueous inorganic salt; and performing a hydrogenation procedure to have the aminocaproic acid intermediate hydrogenated to form a 6-aminocaproic acid product; wherein the solubility regulating agent is selected from the group consisting of the following: benzyl bromide, 2-chlorobenzyl chloroformate, 4-nitrobenzyl chloroformate, benzyl chloroformate, benzyl (4-nitrophenyl) carbonate, and N-(benzyloxycarbonyloxy)succinimide; and aminocaproic acid intermediate is selected from the group consisting of the following: 6-dibenzylamino-hexanoic acid, 6-(2-chloro-benzyloxycarbonylamino)-hexanoic acid, 6-(4-nitro-benzyloxycarbonylamino)-hexanoic acid, and 6-benzyloxycarbonylamino-hexanoic acid.