ATIPAMEZHOLE HYDROCHLORIDE CRYSTALLIZATION METHOD

摘要

The present invention provides a method of isolating atipamezole hydrochloride as a crystalline salt. The method comprises hydrogenation under catalyst of compound of formula (H) in aqueous solution comprising hydrochloric acid, concentrating the solution by distillation, cooling the concentrated solution and recovering the crystallized atipamezole hydrochloride. The product can be recovered directly from aqueous solution without the need to isolate atipamezole base.