2-chloroethyl (5-bromo-2-(4-fluorophenyl)-3-(methylcarbamoyl)benzofuran-6-yl)carbamate (1.00 g, 2.10 mmol) was added to a mixture of KI (0.40 g, 2.10 mmol) and K2CO3 (0.75 g, 6.30 mmol) in DMF (20 mL) and the mixture was stirred under N2 protection at 110° C. for 2 hours. After concentrated in vacuo, the resulting residue was washed with water and EtOAc to provide 5-bromo-2-(4-fluorophenyl)-N-methyl-6-(2-oxooxazolidin-3-yl)benzofuran-3-carboxamide (408 mg, yield: 45%). 1H-NMR (CDCl3, 400 MHz) δ 7.58 (s, 1H), 7.51 (m, 2H), 7.19 (s, 1H), 7.11˜7.13 (d, J=8.0 Hz, 1H), 6.83˜6.88 (m, 1H), 4.37˜7.41 (m, 2H), 4.12˜4.14 (m, 2H), 3.00 (d, J=4.8 Hz, 3H). MS (M+H)+: 433/435.
