反应详情

温度

-78 °C

A solution of 1-Cyclopropyl-3-trifluoromethyl-1H-pyrazole-4-carboxylic acid ethyl ester (Preparation 145, 3.5 g, 14.11 mmol) in dry toluene (70 mL) was cooled to −78° C. and DIBAL-H (29.4 mL of a 1.2 M solution in toluene, 35.3 mmol) was added dropwise to it. The reaction mixture was stirred at −78° C. for 2 hours and then poured into 2N HCl (25 mL) followed by further stirring for 2 hours at room temperature. The mixture was extracted with EtOAc (2×50 mL) and the combined organic layers were washed with water (2×15 mL), brine (15 mL) and dried (Na2SO4) and evaporated in vacuo to afford the title compound as off white solid in 100% yield, 3 g.

1. stirringby further stirring for 2 hours at room temperature
2. extractionThe mixture was extracted with EtOAc (2×50 mL)
3. washthe combined organic layers were washed with water (2×15 mL), brine (15 mL)
4. dry with materialdried (Na2SO4)
5. customevaporated in vacuo