反应详情

To a solution of crude 3-oxo-3-(2-pyridyl)propanenitrile (48.6 g, 331 mmol) in ethanol (500 mL) was added methyl hydrazine (25 g, 543 mmol). The resulting mixture was stirred for about 30 min at rt and then heated at about 75° C. for about 18 h. After cooling to rt the reaction mixture was concentrated in vacuo. The residue was treated with toluene (300 mL). The formed solid was collected by filtration and washed with toluene (150 mL). The solid was dried under vacuum to give 1-methyl-3-(2-pyridyl)pyrazol-5-amine (36.2 g, 208 mmol, 63%). 1H-NMR (CDCl3, Bruker 400 MHz) δ 3.62 (3H, s); 5.34 (2H, br s); 5.90 (1H, s); 7.21 (1H, m); 7.73 (1H, dt, J=10 Hz, 2 Hz); 7.83 (1H, dt, J=10 Hz, 1 Hz); 8.51 (1H, dt, J=6 Hz, 2 Hz).

1. temperatureheated at about 75° C. for about 18 h
2. temperatureAfter cooling to rt the reaction mixture
3. concentrationwas concentrated in vacuo
4. additionThe residue was treated with toluene (300 mL)
5. filtrationThe formed solid was collected by filtration
6. washwashed with toluene (150 mL)
7. customThe solid was dried under vacuum