Process for the preparation of donepezil hydrochloride
AssigneeAlembic Limited
InventorsRavi Ponnaiah, Ashok Prasad, Dineshkumar Ramabhai Panchasara, Gajanan Jijaba Chavan, Bhavesh Hareshbhai Prajapati, Ilesh Mahendrabhai Patel
Life of this patent
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Abstract
The present invention relates to novel process for preparing Donepezil hydrochloride of formula (I)
Claims10
A process for preparation of Donepezil hydrochloride of formula (I)
- comprising a step of condensing bromide salt of formula (IV) with indanone of formula (V)
- to obtain condensed bromide salt of formula (VI).
A process for preparation of Donepezil hydrochloride of formula (I)
- comprising steps of:
- (a) condensing pyridine-4-carboxaldehyde of formula (II) with benzyl bromide of formula (III) to obtain bromide salt of formula (IV)
- (b) condensing bromide salt of formula (IV) in situ with indanone of formula (v) to obtain condensed bromide salt of formula (VI)
A process for preparation of Donepezil hydrochloride of formula (I)
- comprising a step of reducing condensed bromide salt of formula (VI) to obtain Di-Ene intermediate of formula (VII).
A process for preparation of Donepezil hydrochloride of formula (I)
- comprising a step of reducing Di-Ene intermediate of formula (VII) to obtain donepezil free base of formula (VIII).
A novel Di-Ene intermediate of formula (VII)
Use of novel intermediate of formula (VII) for the preparation of Donepezil hydrochloride of formula (I)
A process for preparation of Donepezil hydrochloride of formula (I)
- comprising purification of Di-ene intermediate of formula (VII)
- comprising crystallizing crude Di-ene from a mixture of ethyl acetate, acetone, D M Water and ammonia.
Dependencies are inferred from the claim text.