Potassium Carbonate → Methyl 5-bromo-3-methylbenzofuran-2-carboxylate

To a solution (200 mL) of 1-(5-bromo-2-hydroxyphenyl)ethanone (25.0 g) in N,N-dimethylformamide were added potassium carbonate (24.0 g) and methyl bromoacetate (11.5 mL) at room temperature, and the mixture was stirred at room temperature for 15 hr. The reaction mixture was filtered, 1,8-diazabicyclo[5.4.0]undec-7-ene (23.2 mL) was added to the filtrate, and the mixture was stirred at 100° C. for 3 hr. The reaction mixture was allowed to cool to room temperature, and ice water was added. The precipitate was washed with ethanol-water to give the title object compound (16.8 g, 52%) as a pale-red solid.