反应详情

To a solution of methyl 5-methyl-1-(4-methylbenzyl)-1H-pyrazole-3-carboxylate (Intermediate A, 5.0 g, 20.5 mmol) in THF (100 mL) at 0° C. was added a solution of lithium aluminum hydride (15.4 mL, 30.7 mmol, 2.0 M in THF) dropwise. The mixture was stirred at rt for 1 h. Celite® (3 g) was added to the mixture, followed by water (5 mL) dropwise and sodium hydroxide (1.0 N, 5 mL). The mixture was filtered through a pad of Celite® washing throroughly with ethyl acetate. The combined organics were diluted with ethyl acetate, washed with water (1×150 mL) and brine (1×150 mL), dried over Na2SO4, filtered and concentrated to dryness to afford the title compound as a light yellow solid (4.2 g, 95%): 1H NMR (300 MHz, DMSO-d6) δ 7.10 (d, 2H), 6.96 (d, 2H), 5.98 (s, 1H), 5.14 (s, 2H), 4.89 (t, 1H), 4.29 (d, 2H), 2.24 (s, 3H), 2.14 (s, 3H); ES-MS m/z 217.03, HPLC RT (Method A) 2.96 min.

1. additionCelite® (3 g) was added to the mixture
2. filtrationThe mixture was filtered through a pad of Celite®
3. washwashing throroughly with ethyl acetate
4. additionThe combined organics were diluted with ethyl acetate
5. washwashed with water (1×150 mL) and brine (1×150 mL)
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated to dryness