反应详情

Ethyl 5-methyl-1-phenethylpyrazole-3-carboxylate (3.84 g, 14.9 mM) in ethanol (30 ml) with sodium hydroxide (0.6 g 14.9 mM) was stirred at room temperature for 3 days. The mixture was then diluted with ethyl acetate and water and the layers separated. The organic phase was further extracted with water. The combined aqueous extracts were acidified to pH 2.0 with 5M hydrochloric acid and extracted with dichloromethane. The organic extracts were dried (MgSO4) and evaporated to give the title compound (3.24 g, 95%); υmax(CH2Cl2) 1759 and 1699 cm−1; δH(CDCl3) 1.91 (3H, s), 3.16 (2H, t, J7 Hz), 4.31 (2H, t, J7 Hz), 6.54 (1H, s), 6.98-7.10 (2H, m), and 7.20-7.37 (3H, m).

1. customthe layers separated
2. extractionThe organic phase was further extracted with water
3. extractionextracted with dichloromethane
4. dry with materialThe organic extracts were dried (MgSO4)
5. customevaporated