反应详情

温度

-78 °C

A solution of 1-Cyclopropyl-5-trifluoromethyl-1H-pyrazole-4-carboxylic acid ethyl ester (Preparation 135, 1.4 g, 5.64 mmol) in dry toluene (25 mL) was cooled to −78° C. and DIBAL-H (11.8 mL of 1.2 M solution in toluene, 14.1 mmol) was added dropwise to it. The reaction mixture was stirred at −78° C. for 2 hours and poured into 2N HCl (10 mL). This was stirred for a further 4 hours at room temperature followed by extraction with EtOAc (2×25 mL) and the combined organic layers were washed with water (2×10 mL), brine (10 mL) dried (Na2SO4) and evaporated in vacuo to afford the title compound as off white solid in 100% yield, 1.2 g.

1. stirringThis was stirred for a further 4 hours at room temperature
2. extractionfollowed by extraction with EtOAc (2×25 mL)
3. washthe combined organic layers were washed with water (2×10 mL), brine (10 mL)
4. dry with materialdried (Na2SO4)
5. customevaporated in vacuo