反应详情

A beaker containing 15 mL of 90% fuming nitric acid was cooled in an ice-water bath. 2.1 g (12 mmoles) 4-ethylisatin was added in small portions over a five-minute period. The resultant red-orange solution was stirred while in the ice-water bath for 5 minutes, then warmed to room temperature and stirred for another 10 minutes. A yellow solid precipitated immediately when this solution was poured over crushed ice. 1.4 g (52% yield) 5-nitro-4-ethylisatin was obtained. NMR(CDCl3): 1.29(t,3H, J=7.5 Hz), 3.11(q,2H,J=7.5 Hz), 7.11 (d,1H,J=8.7 Hz), 8.27 (d,1H,J=8.7 Hz), 9.46(bs,1H). MS(m/z): 220(M+).

1. temperaturewas cooled in an ice-water bath
2. customA yellow solid precipitated immediately when this solution
3. additionwas poured
4. customover crushed ice