79865-89-7

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79865-89-7

Using 4-fluorobenzaldehyde (12.4 g, 0.1 mol) and 60% aqueous ethylamine (50 mL, 0.67 mol) as raw materials, the reaction was carried out in a 100 mL autoclave with a stir bar, sealed, and then placed in an oil bath at 130 °C with electromagnetic stirring for 15 h. The mixture was extracted with ethyl acetate three times (50 mL each) and washed with 10% hydrochloric acid twice (50 mL each). After completion of the reaction, the mixture was extracted with ethyl acetate three times (50 mL each time), the organic phases were combined and washed with 10% hydrochloric acid twice (50 mL each time). Subsequently, the pH of the aqueous phase was adjusted to 9 with 10% sodium carbonate solution, and the mixture was again extracted with ethyl acetate three times (30 mL each time), the organic phases were combined and dried with anhydrous sodium sulfate. After drying, the solvent was removed by rotary evaporator to obtain the crude product. The crude product was purified by silica gel column chromatography (200-300 mesh) with dichloromethane as eluent to give 4-(ethylamino)benzaldehyde as a light yellow solid (4 g, 30% yield). The product was analyzed by high resolution mass spectrometry (EI) and the calculated value of C9H11NO was 149.0841 and the measured value of [M + H]+ was 149.0840.