A mixture of ethyl 2-ethyl-4-hydroxy-1-benzofuran-6-carboxylate (0.80 g, 3.4 mmol), 4-fluorophenyl methyl sulfone (0.60 g, 3.4 mmol) and Cs2CO3 (1.12 g, 3.4 mmol) in DMF (40 mL) was heated to 100° C. overnight. The reaction was monitored by TLC (petroleum ether/EtOAc 4:1). The mixture was poured into water (50 mL) and extracted with EtOAc (90 mL×3). The organic layer was washed with brine (50 mL×2), dried over Na2SO4 and concentrated. The product was purified via column chromatography on silica gel eluted with petroleum ether/EtOAc (20:1) to afford the desired compound (0.80 g, 60%) as a colorless oil.
