IMPROVED PROCESS FOR THE PREPARATION OF ENTACAPONE

摘要

The invention disclosed in this application relates to an improved process for the preparation of Entacapone. In one embodiment the process involves: (i) reacting a 3-alkoxy-4-hydroxy-5-nitrobenzadehyde with N,N-diethylaminocyanoacetamide in the presence of a mild acid catalyst and a solvent, to provide a 3-O-alkylated Entacapone, and treating the 3-O-alkylated Entacapone with an acid catalyst in the presence of an organic base to provide Entacapone.