General procedure for the synthesis of 1-amino-2-cyano naphthalene from 1-nitronaphthalene and ethyl cyanoacetate: In a dry 2L reactor, 139.8 g (1.236 mol) of ethyl cyanoacetate, 29.5 g (0.453 mol) of potassium cyanide, 46.2 g (0.824 mol) of potassium hydroxide, and 920 mL of dimethylformamide were added, and dissolved with stirring at 10 °C. Stirring was continued for 20 minutes under nitrogen protection. Subsequently, the reaction mixture was heated to 60°C and the reaction was stirred for 4 hours. Upon completion of the reaction, the reaction solvent was concentrated and 600 mL of 10% aqueous sodium hydroxide solution was added and stirred under reflux conditions for 1 hour. The reaction mixture was filtered and purified by column chromatography using dichloromethane and heptane as eluents to give 50 g (yield: 60%) of the target product labeled as [Intermediate 1-a].
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