- A PROCESS FOR PREPARATION OF INTERMEDIATES OF DONEPEZIL HYDROCHLORIDE
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The present invention provides a process for the preparation of key intermediate for the synthesis 5,6-dimethoxy-2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1-indanone hydrochloride (donepezil hydrochloride). The present invention particularly provides a process for the preparation of 5,6-dimethoxy-2-(4-pyridylmethylene)-1-indanone comprising condensation of 5,6-dimethoxy-1-indanone with 4- pyridinecarboxaldehyde using an alkali metal hydroxide as a mild base in the presence of demineralized water as a solvent at a temperature in the range of 15°C to 45°C to yield 5,6-dimethoxy-2-(4-pyridylmethylene)-1-indanone, which is subsequently benzylated using benzyl bromide in the presence of solvent at a reflux temperature to yield 1-benzyl-4-[(5,6-dimethoxy-1-indanone-2-yl)methylene]pyridinium bromide.
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Page/Page column 17-18
(2012/10/18)
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- A PROCESS FOR THE PREPARATION OF DONEPEZIL HYDROCHLORIDE
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The present invention relates to novel process for preparing Donepezil hydrochloride of formula (I)
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Page/Page column 14-15
(2010/08/05)
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