反应详情

温度

0 °C

An ice-cooled solution of sodium nitrite (3.55 g, 51 mmol) in water (10 mL) was added dropwise to a stirred, cooled (0° C.) solution of 2-cyclopropoxy-5-(trifluoromethoxy)benzeneamine (Description 7, 4.8 g, 20.6 mmol) in aqueous hydrochloric acid (5M, 300 mL), maintaining the internal temperature at 0° C. The mixture was stirred at 0° C. for 30 min., then potassium iodide (8.55 g, 51.5 mmol) in water (10 mL) was added dropwise, maintaining the internal temperature at 0° C. The mixture was stirred at 0° C. for 30 min., then allowed to warm up to room temperature and stirred until nitrogen evolution ceased. The mixture was extracted with ether, the organic fraction was washed with aqueous sodium thiosulfate (10%), dried (MgSO4), and the solvent was evaporated under reduced pressure. The residue was purified by flash column chromatography on silica gel, eluting with hexane/Et2O (98:2 increasing to 95:5), to give the title compound as a colourless oil (6.23 g, 88%). 1H NMR (360 MHz, CDCl3) δ 7.62 (1H, d, J 2.4 Hz), 7.20 (1H, dd, J 9.1, 2.4 Hz), 7.15 (1H, d, J 9.1 Hz), 3.80 (1H, m), and 0.83 (4H, m).

1. additionwas added dropwise to a stirred
2. temperaturemaintaining the internal temperature at 0° C
3. stirringThe mixture was stirred at 0° C. for 30 min.
4. temperatureto warm up to room temperature
5. stirringstirred until nitrogen evolution
6. extractionThe mixture was extracted with ether
7. washthe organic fraction was washed with aqueous sodium thiosulfate (10%)
8. dry with materialdried (MgSO4)
9. customthe solvent was evaporated under reduced pressure
10. customThe residue was purified by flash column chromatography on silica gel
11. washeluting with hexane/Et2O (98:2 increasing to 95:5)