Acetophenone (25 mmol), methylamine hydrochloride (27.5 mmol), formaldehyde (35 mmol) and concentrated hydrochloric acid (0.125 mmol) were mixed in ethanol (12.5 mL). The mixture was placed in a sealed container and heated for 20 hours for the reaction. After completion of the reaction, it was cooled to room temperature. The solvent was removed by distillation under reduced pressure, followed by addition of ethyl acetate (25 mL) and continued stirring for 4 hours. The crude product was collected by filtration, washed with ethyl acetate and finally purified by recrystallization from isopropanol to afford the target product 3-(methylamino)-1-phenylpropan-1-one hydrochloride (Product 2a). Yield: 60-70%.
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