反应详情

温度

180 °C

Toluene-4-sulfonic acid 5-acetyl-4-(2-fluorophenyl)-1H-pyrazol-3-yl ester (8.26 g, 22.1 mmol) and 2-fluorobenzhydrazide (3.86 g, 25.0 mmol) were stirred together in xylene (250 ml) at reflux overnight. The solvent was removed in vacuo, and the residue was heated in Dowtherm A at 180° C. for 2 h. The mixture was poured directly onto a column of silica gel, and the Dowtherm was eluted off with dichloromethane before eluting the product off with 10% ethyl acetate in dichloromethane (UV detection). Toluene-4-sulfonic acid 3,7-bis(2-fluorophenyl)-4-methylpyrazolo[1,5-d][1,2,4]triazin-2-yl ester was obtained as a yellow solid (6.62 g). 1H NMR (400 MHz, CDCl3) δ 2.43 (3H, s), 2.53 (3H, s), 7.17-7.37 (6H, m), 7.41-7.51 (2H, m), 7.63 (1H, m), 7.69 (3H, m); MS (ES+) m/e 493 [MH]+.

1. temperatureat reflux overnight
2. customThe solvent was removed in vacuo
3. additionThe mixture was poured directly onto a column of silica gel
4. washthe Dowtherm was eluted off with dichloromethane
5. washbefore eluting the product off with 10% ethyl acetate in dichloromethane (UV detection)