Hydrochloric Acid → Donepezil Hydrochloride

HRID 1454360

Reaction equation

HRID 1454360 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[C:5]2[CH2:14][CH:13]([CH2:15][CH:16]3[CH2:21][CH2:20][N:19]([CH2:22][C:23]4[CH:24]=[CH:25][CH:26]=[CH:27][CH:28]=4)[CH2:18][CH2:17]3)[C:11](=[O:12])[C:6]2=[CH:7][C:8]=1[O:9][CH3:10].[ClH:29]>C(O)C>[CH3:1][O:2][C:3]1[CH:4]=[C:5]2[CH2:14][CH:13]([CH2:15][CH:16]3[CH2:17][CH2:18][N:19]([CH2:22][C:23]4[CH:28]=[CH:27][CH:26]=[CH:25][CH:24]=4)[CH2:20][CH2:21]3)[C:11](=[O:12])[C:6]2=[CH:7][C:8]=1[O:9][CH3:10].[ClH:29]

Participants

4

Reactant 2

HCID 313Hydrochloric AcidHCID 3152Donepezil

Product 1

HCID 5741Donepezil HydrochlorideYield 95.3%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Conditions

Temperature
9 °C

Procedure

50 g of donepezil was dissolved by stirring in 240 g of ethanol under heating, followed by adding 15.1 g of concentrated hydrochloric acid thereto at the internal temperature of 30° C. Then, it was cooled and continued stirring while keeping the internal temperature at about 25° C. Crystals started precipitating about 1 hour after the concentrated hydrochloric acid was poured into the mixture. After the precipitation started, the mixture was stirred at the internal temperature of 25° C. for 17 hours and then cooled to the internal temperature of 9° C. The crystals were collected by filtration and dried about 3 hours after the cooling was started, to give 52.25 g of polymorphic crystal (III) of donepezil hydrochloride (yield: 95.3%).

Workup

  1. temperatureunder heating
  2. customat the internal temperature of 30° C
  3. temperatureThen, it was cooled
  4. customat about 25° C
  5. customCrystals started precipitating about 1 hour after the concentrated hydrochloric acid
  6. additionwas poured into the mixture
  7. customAfter the precipitation
  8. stirringthe mixture was stirred at the internal temperature of 25° C. for 17 hours
  9. filtrationThe crystals were collected by filtration
  10. customdried about 3 hours after the cooling

Sources & evidence

ORD record
ord-03340c938c664c9abbd4b96929af37bd
Source dataset
uspto-grants-2009_01
Patent number
US07479563B2

Linked notes

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