反应详情

温度

90 °C

A 3-neck round bottomed flask (100 mL) was charged with ethyl 3-chloro-1-(pyridin-3-yl)-1H-pyrazole-5-carboxylate (0.200 g, 0.795 mmol) and hydrochloric acid (37%, 4 mL). The reaction was heated at 90° C. for 18 hours and allowed to cool to 20° C. Dioxane (5 mL) was added to the resulting suspension and was concentrated to dryness. Dioxane (5 mL) was added and the suspension was concentrated again to afford a white solid. Dioxane (5 mL) was added and the resulting suspension was stirred for 1 hour at 20° C. The solid was filtered and the solid was rinsed with dioxane (2 mL). The filter cake was dried under vacuum at 20° C. to afford the title compound as a white solid (0.218 g, 100%): 1H NMR (400 MHz, DMSO-d6) δ 9.05 (dd, J=2.5, 0.7 Hz, 1H), 8.84 (dd, J=5.3, 1.4 Hz, 1H), 8.41 (ddd, J=8.3, 2.5, 1.4 Hz, 1H), 7.88 (ddd, J=8.3, 5.2, 0.7 Hz, 1H), 7.26 (s, 1H); 13C NMR (101 MHz, DMSO-d6) δ 158.71, 146.00, 143.44, 140.36, 137.76, 137.00, 136.83, 125.19, 111.71.

1. temperatureto cool to 20° C
2. concentrationwas concentrated to dryness
3. additionDioxane (5 mL) was added
4. concentrationthe suspension was concentrated again
5. customto afford a white solid
6. filtrationThe solid was filtered
7. washthe solid was rinsed with dioxane (2 mL)
8. customThe filter cake was dried under vacuum at 20° C.