1.03 g (4.74 mmol) of 3-oxo-N-(3-phenyl-2-propene-1-yl)butyramide, 723 mg (4.78 mmol) of 3-nitrobenzaldehyde and 0.2 ml (2.02 mmol) of piperidine were heated under reflux in the presence of a catalytic amount of p-toluenesulfonic acid in 30 ml of benzene overnight while water was removed. Ethyl acetate was added to the reaction mixture. After washing with 2 N hydrochloric acid and then with a saturated aqueous sodium hydrogencarbonate solution, the organic layer was dried over anhydrous sodium sulfate. After the concentration under reduced pressure, the residue was purified by the silica gel chromatography (hexane/ethyl acetate=2/1) to obtain the title compound.
