反应详情

温度

50 °C

To ice-water bath cooled, conc. H2SO4 (10 mL) was added 2-amino-5-trifluoromethylpyridine (1.70 g, 10.5 mmol). The resulting solution was heated to 50° C. and 69-71% HNO3 (1.7 mL, 2.6 mmol) was added dropwise over 10 min with stirring. The resulting solution was stirred at 80° C. for 46 h, then allowed to cool to room temperature, poured into ice-water (100 mL) and basified to pH 9 with 40% aq NaOH. The resulting mixture was extracted with EtOAc (5×40 mL). The EtOAc solution was dried (MgSO4), and evaporated to give 1.33 g (61%) of 50 as a yellow powder, mp 191°-3° C. 1H NMR (CDCl3), 6.140 (bs, 1H), 7.916 (bs, 1H), 8.590 (s, 1H), 8.670 (s, 1H).

1. temperatureTo ice-water bath cooled
2. stirringThe resulting solution was stirred at 80° C. for 46 h
3. temperatureto cool to room temperature
4. extractionThe resulting mixture was extracted with EtOAc (5×40 mL)
5. dry with materialThe EtOAc solution was dried (MgSO4)
6. customevaporated