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US 2006/0041140 A1Published application
Preparation of intermediates for acetyl cholinesterase inhibitors
AssigneeHetero Drugs Limited
InventorsReddy Parthasardhi, Reddy Rathnakar, Reddy Raji, Reddy Muralidhara
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Abstract
A simple, industrial process for the preparation of the intermediates of acetyl cholinesterase inhibitors is provided. Thus, for example, 5,6-dimethoxy-2-(4-pyridyl)methyl-1-indanone is hydrogenated using platinum oxide catalyst in the presence of hydrochloric acid under a pressure of 2 bars to give 4-[(5,6-dimethoxy-1-indanon)-2-yl]methylpiperidine hydrochloride, which is then converted to donepezil hydrochloride, an acetyl cholinesterase inhibitor.
Claims13
1) A process for the preparation of the compound of the general formula I or a salt thereof:
- wherein R represents, the same as or different from each other, a hydrogen atom or a lower alkoxy group, n represents an integer of 1 to 4 and Y represents H or F, which comprises hydrogenating the compound of the general formula II:
- wherein R, n and Y have the same meaning as defined above, with hydrogen using platinum oxide, palladium-carbon, raney nickel or ruthenium oxide catalyst in the presence of an acid under a hydrogen pressure of 1 to 10 bars and optionally converting the compound of the formula I to the salt.
Dependencies are inferred from the claim text.