反应详情

Treat a solution of 2-(2-bromo-4-fluoro-5-nitrophenyl)acetic acid (30.0 g, 0.11 mol) in acetic anhydride (30 mL) with 1-methylimidazole (4.5 g, 55 mmol), stir at RT for 2 h, treat with water, stir for 5 min, and extract with EtOAc. Wash the combined organics with water, saturated. Na2CO3, then brine, dry over Na2SO4, concentrate and purify via silica gel chromatography (EtOAc/petroleum ether) to afford the title compound (12 g, 40% yield). 1H NMR (400 MHz, DMSO-d6): δ 8.19 (d, J=8.0 Hz, 1H), 8.02 (d, J=10.8 Hz, 1H), 4.09 (s, 2H), 2.23 (s, 3H).

1. stirringstir for 5 min
2. extractionextract with EtOAc
3. washWash the combined organics with water
4. dry with materialNa2CO3, then brine, dry over Na2SO4
5. concentrationconcentrate
6. custompurify via silica gel chromatography (EtOAc/petroleum ether)