反应详情

温度

2.5 °C

Commercially available 4-nitro-isoindole-1,3-dione (1) (25 g, 0.13 mol) was stirred in water (300 mL) at 0° C. Over a few minutes, an aqueous solution of sodium hydroxide (30% w/w, 35 g, 0.26 mol) was added. The mixture was stirred for 1.5 h at 0-5° C. The cold solution was acidified with concentrated HCl (22 mL, 0.26 mol) and the product precipitated as a white solid. After allowing to stand overnight in a refrigerator, the mixture was filtered to afford the title compound (26.3 g, 96%) as a white solid: 1H NMR (300 MHz, DMSO) δ 8.2 (s, 1H), 8.15 (d, 1H), 7.93 (d, 1H), 7.88-7.65 (m, 2H); ESIMS m/z 211 ([M+H]+), m/z 209 ([M−H]−).

1. waitOver a few minutes
2. customthe product precipitated as a white solid
3. waitto stand overnight in a refrigerator
4. filtrationthe mixture was filtered