反应详情

Sulfuric acid (1 mL, 18.76 mmol) was added to a suspension of 6-nitro-1H-indole-2-carboxylic acid (0.5 g, 2.425 mmol) in methanol (5 mL). The mixture was heated to reflux for 2 h. The reaction mixture was cooled to RT, poured into ice/water, neutralized with sodium bicarbonate, and extracted with ethyl acetate. The organic extracts were combined, dried over sodium sulfate, and concentrated to give the title compound (0.433 g, 81%) as a yellow solid. 1H NMR (400 MHz, CDCl3): δ ppm 9.31 (s, 1H), 8.41 (s, 1H), 8.05 (dd, 1H), 7.79 (d, 1H), 7.29 (s, 1H), 3.70-4.24 (m, 3H). MS: m/z 221 (M+1).

1. temperatureThe mixture was heated
2. temperatureto reflux for 2 h
3. extractionextracted with ethyl acetate
4. dry with materialdried over sodium sulfate
5. concentrationconcentrated