反应详情

温度

100 °C

To a mixture of 5-(difluoromethoxy)-1H-indazole-3-carboxylic acid (1 g, 4.38 mmol), and sodium bicarbonate (1.22 g, 563 μL, 14.5 mmol) in dichloroethane (10.0 mL) and water (10.0 mL) were added in one portion sodium iodide (1.71 g, 11.4 mmol) and iodine (1.45 g, 5.7 mmol) and the mixture heated at to 100° C. (oil bath temperature) with vigorous stirring for 45 minutes. After cooling to 25° C. the mixture was diluted with dichloromethane then washed with 10% Na2S2O3 and saturated NaHCO3. The organic phases were combined, dried (MgSO4) and concentrated to an off-white solid which was dissolved in dichloromethane, hexane added to promote solid formation and allowed to stand. The solid formed was separated by decanting the mother liquor and dried to give 5-(difluoromethoxy)-3-iodo-1H-indazole (1145 mg, 3.69 mmol, 84.3%) as a white fluffy solid. MS (M−H)−=308.9; 1H NMR (CDCl3) δ: 7.52 (d, J=9.1 Hz, 1H), 7.28-7.36 (m, 1H), 6.57 (t, J=73.7 Hz, 1H).

1. temperatureAfter cooling to 25° C. the mixture
2. washthen washed with 10% Na2S2O3 and saturated NaHCO3
3. dry with materialdried (MgSO4)
4. concentrationconcentrated to an off-white solid which
5. dissolutionwas dissolved in dichloromethane
6. additionhexane added
7. customThe solid formed
8. customwas separated
9. customby decanting the mother liquor
10. customdried