US Patent 7446203 Preparation of intermediates for acetycholinesterase inhibitors

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.