Nalmefene hydrochloride → Nalmefene hydrochloride dihydrate

Participants

Reaction Conditions

Reaction Steps

Crude Nalmefene hydrochloride (7.67 Kg, assay 93.9%) and water (8.6 liter) were charged into a suitable reactor. The suspension was heated up to 80° C. until the substrate completely dissolved. Vacuum was then applied to remove organic solvents. The resulting solution was then filtered through a 0.65 μm cartridge and then diluted with water (2.1 liter) used to rinse the reactor and pipelines. The solution was cooled down to 50° C. and 7 g of Nalmefene hydrochloride dihydrate seeding material was added. The mixture was cooled down to 0-5° C. in one hour under efficient stirring and then maintained under stirring for one additional hour. The solid was filtered and washed with acetone. The wet product was dried at 25° C. under vacuum to provide Nalmefene hydrochloride dihydrate (5.4 Kg; yield 73%) with a chemical purity of 99.89% (HPLC).

Provenance & Evidence