Ethyl p-bromophenylacetate (972.4 mg, 4 mmol), paraformaldehyde (240 mg, 8 mmol) and Bu4NCl (22 mg, 0.08 mmol) were used as raw materials, which were dissolved in DMF (10 mL), followed by the addition of K2CO3 (1.32 g, 9.6 mmol). The reaction mixture was heated and stirred at 60°C for 2 hours. After completion of the reaction, the mixture was cooled to room temperature, diluted with EtOAc (30 mL) and washed sequentially with water (20 mL × 3) and brine. The organic phase was dried with Na2SO4, filtered and concentrated under reduced pressure. The residue was purified by rapid column chromatography on silica gel to afford ethyl 2-(4-bromophenyl)acrylate as a white solid (0.74 g, 73% yield). Mass spectrometry analysis: calculated value 255 (MH+), measured value 255 (MH+).
