23499-01-6

General procedure for the synthesis of 1-(4-nitrophenyl)-piperidin-4-one from p-fluoronitrobenzene: To acetonitrile (20 mL) were added 4-piperidinone hydrochloride (2.17 g, 16.0 mmol), triethylamine (3.9 mL), and potassium carbonate (2.9 g, 21.0 mmol) sequentially. After stirring for 20 minutes at room temperature, 1-fluoro-4-nitrobenzene (1 g, 7.09 mmol) was added and the reaction mixture was heated to reflux for 12 hours. After completion of the reaction, it was cooled to room temperature, filtered and the filtrate was concentrated under reduced pressure to obtain the crude product. The crude product was dissolved in water and extracted with ethyl acetate, the organic phase was dried over anhydrous sodium sulfate and the solvent was evaporated under reduced pressure to give 1-(4-nitrophenyl)-piperidin-4-one (0.6 g, 38% yield).

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