反应详情

To toluene-4-sulfonic acid 4-(2-fluorophenyl)-5-(1-hydroxyethyl)-1H-pyrazol-3-yl ester (16.4 g, 43.6 mmol) in dichloromethane (500 ml) was added pyridinium dichromate (19.7 g, 52.3 mmol) and the resulting slurry was stirred at room temperature for 1 h. The mixture was poured directly onto a column of silica gel, and the product was eluted off with ethyl acetate, yielding toluene-4-sulfonic acid 5-acetyl-4-(2-fluorophenyl)-1H-pyrazol-3-yl ester as a yellow solid (8.64 g). 1H NMR (400 MHz, CDCl3) δ 2.16 (3H, s), 2.43 (3H, s), 7.09 (1H, m), 7.22 (3H, m), 7.34 (1H, m), 7.41 (1H, m), 7.65 (2H, d, J=6.8 Hz); MS (ES+) m/e 375 [MH]+.

1. additionThe mixture was poured directly onto a column of silica gel
2. washthe product was eluted off with ethyl acetate