Scheme 2. Reaction scheme for agomelatine synthesis. (7-methoxy-1-naphthyl)acetonitrile reacts with hydrogen with Raney nickel as the catalyst in ammonia and ethanol to form the hydrogenated amine main product (intermediate) . The disubstituted compound is formed as the main impurity, and the amine group of the intermediate can also be ethylated giving impurity . Note that reactions are not balanced.