Hydrochloric Acid → Donepezil Hydrochloride

Participants

Reaction Steps

After completing the hydrogenation, the catalyst was removed from the reaction solution followed by concentration. To the concentrated residue, 700 ml of ethanol was added to obtain a solution. Subsequently, the solution was crystallized under stirring. Precipitated crystals were filtered out, and then dried to obtain 74.9 g of donepezil. The obtained donepezil (74.8 g) was dissolved in 598 ml of ethanol. To the mixture, 22.5 g of concentrated hydrochloric acid was added under stirring, and the mixture was converted into its hydrochloride. The precipitated crystals were filtered out, and then dried to obtain 78.7 g of donepezil hydrochloride. The values of 1H-NMR of donepezil hydrochloride were consistent with those of Example 3.

Provenance & Evidence