反应详情

A mixture of 5-bromo-3-(methylcarbamoyl)-6-(N-methylmethylsulfonamido)benzofuran-2-carboxylic acid (1 g, 2.47 mmol), HOBT (500 mg, 3.70 mmol) and EDCI (946 mg, 4.94 mmol) in DMF (20 mL) was stirred at room temperature under N2 for 2 h. Et3N (1.25 g, 12.34 mmol) and N,O-dimethylhydroxylamine hydrochloride (1.03 g, 12.34 mmol) were added, then the mixture was stirred for 18 h. The mixture was concentrated, diluted with water, extracted with EA, the organic layers were washed with Na2CO3 (a.q.), brine, dried over Na2SO4, concentrated. The residue was purified by column chromatography (DCM:EA=20:1) to get product 5-bromo-N2-methoxy-N2,N3-dimethyl-6-(N-methylmethylsulfonamido)benzofuran-2,3-dicarboxamide (0.68 g, yield: 62%). 1H-NMR (CDCl3, 400 MHz) δ 8.83 (s, 1H), 8.74 (s, 1H), 7.72 (s, 1H), 3.89 (s, 3H), 3.42 (s, 3H), 3.34 (s, 3H), 3.08 (s, 3H), 2.98 (d, J=4.8 Hz, 3H). MS (M+H)+: 448/450.

1. stirringthe mixture was stirred for 18 h
2. concentrationThe mixture was concentrated
3. additiondiluted with water
4. extractionextracted with EA
5. washthe organic layers were washed with Na2CO3 (a.q.), brine
6. dry with materialdried over Na2SO4
7. concentrationconcentrated
8. customThe residue was purified by column chromatography (DCM:EA=20:1)