Ammonia → Donepezil Hydrochloride

Participants

Reaction Conditions

Reaction Steps

Donepezil oxalate (purified, example 2), 5 gms, was dissolved in water 50 ml under heating at 50° C. Stirring was continued for 1 hour with gradual cooling. At room temperature, dichloromethane 50 ml was added and stirred for 10 mins. Liquid Ammonia 5 ml was added slowly with stirring. The dichloromethane layer was separated and 50 ml water was added to it. Analytical grade concentrated hydrochloric acid 1.5 ml was slowly added and stirred for 10 mins. Dichloromethane was distilled off under vacuum at 45° C. to obtain Donepezil hydrochloride in water, which was kept for lyophilyzation for 24 hours at −35° C. to give Donepezil hydrochloride amorphous with a yield of 3.9 gms (95%).

Provenance & Evidence