反应详情

温度

0 °C

To a cooled solution (0° C.) of 1,3-dimethyl-1H-pyrazole-4-carboxylic acid ethyl ester (5.0 g, 29.7 mmol) in anhydrous tetrahydrofuran (1000 ml), is added a solution of DIBAL-H (95.1 ml, 95.1 mmol). The reaction mixture is stirred at 0° C. for 2 hours and then quenched with saturated aqueous sodium potassium tartrate and stirred for 2 hours. The layers are separated and the aqueous layer is extracted with ethyl acetate. The combined organic extracts are dried over anhydrous Na2SO4, filtered, and concentrated in vacuo to give 1,3-dimethyl-1H-pyrazol-4-methanol (3.7 g, 100%) which is used without purification. 1H NMR (CDCl3): δ=7.22 (1H, s), 4.46 (2H, s), 3.74 (3H, s), 2.20 (3H, s).

1. customquenched with saturated aqueous sodium potassium tartrate
2. stirringstirred for 2 hours
3. customThe layers are separated
4. extractionthe aqueous layer is extracted with ethyl acetate
5. dry with materialThe combined organic extracts are dried over anhydrous Na2SO4
6. filtrationfiltered
7. concentrationconcentrated in vacuo