[Br:1][C:2]1[C:3]([NH:16][S:17]([CH3:20])(=[O:19])=[O:18])=[CH:4][C:5]2[O:9][C:8]([I:10])=[C:7]([C:11]([NH:13][CH3:14])=[O:12])[C:6]=2[CH:15]=1.[C:21]([O-])([O-])=O.[K+].[K+].CI>CN(C=O)C>[Br:1][C:2]1[C:3]([N:16]([CH3:21])[S:17]([CH3:20])(=[O:18])=[O:19])=[CH:4][C:5]2[O:9][C:8]([I:10])=[C:7]([C:11]([NH:13][CH3:14])=[O:12])[C:6]=2[CH:15]=1To a suspension of 5-bromo-2-iodo-N-methyl-6-(methylsulfonamido)benzofuran-3-carboxamide (177 mg, 90% purity, 0.34 mmol) and K2CO3 (140 mg, 1.01 mmol) in DMF (3 mL) was added dropwise CH3I (79 mg, 0.68 mol) at 0° C. under N2, and then the mixture was stirred at 80° C. for 1 hour. After concentrated in vacuum, the residue was suspended in H2O and extracted with DCM. The residue was purified by column chromatography (eluted with DCM: EtOAc from 10:1 to 2:1) to give 5-bromo-2-iodo-N-methyl-6-(N-methylmethylsulfonamido)benzofuran-3-carboxamide (150 mg, yield: 90%). 1H-NMR (CDCl3, 400 MHz) δ 8.38 (s, 1H), 7.66 (s, 1H), 6.27 (s, 1H), 3.32 (s, 3H), 3.08 (d, J=4.8 Hz, 3H), 2.89 (s, 3H). MS (M+H)+: 487/489.
Wird geladen…
