反应详情

温度

60 °C

A mixture of 3,5-difluorophenol (25 g, 0.19 mol) and KOH (85%, 12.7 g, 0.19 mol) was treated dropwise with water (50 mL), stirred at 60° C. for 1 h, treated dropwise with formaldehyde solution (37%, 15.6 mL, 0.19 mol) and water (50 mL) and stirred overnight at 40° C. The mixture was cooled, acidified with 6-M HCl, filtered and the resulting solid washed with water and dried to give the title compound (15 g, 49%) as a white solid: NMR δH (400 MHz, DMSO) 10.28 (1H, s), 6.43 (2H, m), 4.99 (1H, t, J 5.6 Hz) and 4.37 (2H, d, J 5.6 Hz).

1. stirringstirred overnight at 40° C
2. temperatureThe mixture was cooled
3. filtrationfiltered
4. washthe resulting solid washed with water
5. customdried