To 4-((E)-2-dimethylamino vinyl) nicotinonitrile (253 g) was added ammonium formate (810 g) followed by acetic acid (300 mL) in a 4 L reaction vessel. The reaction mixture was heated to reflux at 115°C for 20 hours. Upon completion of the reaction, it was cooled to room temperature, diluted with the addition of water (5 L) and extracted several times with dichloromethane (0.5 L x 10). After combining the organic phases, the pH of the aqueous phase was adjusted with sodium hydroxide (160 g) to 10. Subsequently, the aqueous phase was extracted with methyl tert-butyl ether, and the organic phase was separated and dried with anhydrous sodium sulfate. The solvent was removed by concentration under reduced pressure, and after drying, 2,7-naphthyridin-1-amine (59 g) was obtained with a molecular weight of 145.16 g/mol (M+H measured value of 146), and the NMR spectrum was consistent with the target product.