反应详情

温度

-10 °C

Into a 500 mL flask was weighed 3.84 g (12.6 mmol) of 2-(2-chlorophenyl)-5-trifluoromethyl-2H-pyrazole-3-carboxylic acid methyl ester and 50 mL of anhydrous THF. The solution was cooled to approximately −10° C. in an ice-methanol bath and 1.0 M DIBAL-H in THF was added (50 mL). The reaction was allowed to warm to room temperature over 30 minutes and remained at room temperature for another 1 h. The reaction was concentrated in vacuo to remove THF then was washed into a separatory funnel with ethyl acetate and saturated sodium potassium tartrate. The ethyl acetate was separated, washed with brine, dried (Na2SO4), and concentrated in vacuo. The crude [2-(2-chloro-phenyl)-5-trifluoromethyl-2H-pyrazol-3-yl]-methanol was recovered as a colorless oil, yield: 3.54 g; 1H NMR (400 MHz, CDCl3): δ 7.33-7.50 (m, 4H), 6.64 (s, 1H), 4.45 (s, 2H); MS (ES): 277 [M+H]+.

1. customInto a 500 mL flask was weighed
2. temperatureto warm to room temperature over 30 minutes
3. concentrationThe reaction was concentrated in vacuo
4. customto remove THF
5. washthen was washed into a separatory funnel with ethyl acetate and saturated sodium potassium tartrate
6. customThe ethyl acetate was separated
7. washwashed with brine
8. dry with materialdried (Na2SO4)
9. concentrationconcentrated in vacuo
10. customThe crude [2-(2-chloro-phenyl)-5-trifluoromethyl-2H-pyrazol-3-yl]-methanol was recovered as a colorless oil, yield: 3.54 g