Improved preparation method of captopril

• Main Authors: ZENG WEI, LIU YUTING, FU LIN, DAI XIANPENG
• Format: Patent
• Language: Chinese; English
• Published: 03.04.2020
• Subjects: CHEMISTRY; HETEROCYCLIC COMPOUNDS; METALLURGY; ORGANIC CHEMISTRY

The invention discloses an improved preparation method of captopril. The method comprises the following steps: adding free acid and water, stirring and dissolving at 40-60 DEG C under the protection of nitrogen, dropwisely adding hydrochloric acid, and keeping the temperature to react for 1-3 h; adding medicinal carbon, and decolorizing the obtained solution for 0.5-1.0 h; carrying out pressure filtration by using nitrogen to make the decolorized solution enter a crystallizing tank, pressurizing the crystallizing tank by using nitrogen, and slowly carrying out cooling crystallization; and performing suction filtration and drying to obtain the captopril. Compared with existing preparation methods, the method of the invention has the advantages of simplicity, mild reaction conditions, easiness in process control, few side reactions, easiness in separation and purification, obtaining of the final product with a high purity, low cost, high yield, few three wastes, small pollution and suitableness for industrial p