反应详情

温度

-20 °C

A solution of 2-o-tolylacetic acid (3.54 g, 23.6 mmol) in DCM (12 mL) was added to a pre-cooled mixture of concentrated sulfuric acid (10 mL, 188 mmol) and 90% nitric acid (1 mL, 22.4 mmol) at −20° C. The reaction mixture was stirred at −20° C. for 30 minutes, then slowly warmed to room temperature and stirred overnight. The reaction mixture was poured into ice-water. The white solid was collected by filtration, rinsed with water, and concentrated. The solid was triturated with ether and filtered to obtain Intermediate 80A (2.4 g, 42%) as a white solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 12.62 (1H, br. s.), 8.13 (1H, d, J=2.51 Hz), 8.04 (1H, dd, J=8.28, 2.51 Hz), 7.47 (1H, d, J=8.53 Hz), 3.80 (2H, s), 2.34 (3H, s).

1. temperatureslowly warmed to room temperature
2. stirringstirred overnight
3. filtrationThe white solid was collected by filtration
4. washrinsed with water
5. concentrationconcentrated
6. customThe solid was triturated with ether
7. filtrationfiltered