反应详情

To a solution of ethyl 1-(2-chloropyrimidin-4-yl)-3-methyl-1H-pyrazole-4-carboxylate intermediate 1 (6.5 g, 24.0 mmol) in 50 mL of anhydrous tetrahydrofuran (THF), was slowly added 109 mL (4.5 equiv.) of 1M solution of di-isobutylaluminum hydride (DIBAL-H) in toluene with ice bath cooling. After being stirred for 2 hours at room temperature, the reaction was quenched by slow addition of 1N—NaOH solution. It was diluted with ethyl acetate and washed with brine. The collected organic layer was dried over anhydrous sodium sulfate and then partially concentrated in vacuo. To this, was heptane added to form pale yellow precipitates. The resulting solids were collected by filtration and rinsed with heptanes and then dried under high vacuum to give 3.6 g (66%) of intermediate alcohol 6. MS (ESI) m/z 225 [M+H]+.

1. temperaturecooling
2. customthe reaction was quenched by slow addition of 1N—NaOH solution
3. additionIt was diluted with ethyl acetate
4. washwashed with brine
5. dry with materialThe collected organic layer was dried over anhydrous sodium sulfate
6. concentrationpartially concentrated in vacuo
7. additionadded
8. customto form pale yellow precipitates
9. filtrationThe resulting solids were collected by filtration
10. washrinsed with heptanes
11. customdried under high vacuum