Patent ID: 7501519

Claim:
A method for producing biperiden by reacting exo-l-(bicyclo[2.2.1]hept-5-en-2-yl)-3-piperidino-l-propanone with a phenylmagnesium compound, characterized in that the production of the exo-1-(bicyclo(2.2.1]hept-5-en-2-yl)-3-piperidino-l-propanone comprises the following steps: a) conversion of exo-l-(bicyclo[2.2.1]hept-5-en-2-yl)-ethanone into an exo silyl enol ether IV in which R 3 may be identical or different and is alkyl or cycloalkyl, and b) reaction of the exo silyl enol ether with an N-methylenepiperidinium compound.