反应详情

温度

-78 °C

Dissolve dimethyl sulfoxide (0.751 mL, 10.6 mmol) in DCM (20 mL) and cool to −78° C. Add oxalyl chloride (0.577 mL, 6.62 mmol) dropwise in DCM (8 mL) and stir for 15 min. Add (5-methyl-1-pyridin-2-yl-1H-pyrazol-4-yl)-methanol (0.501 g, 2.65 mmol) in DCM (20 mL) dropwise and stir for 1 hr. at −78° C. Add triethylamine (1.85 mL, 13.2 mmol) and warm the mixture to room temperature for 1 hr. Dilute the mixture with saturated sodium bicarbonate and extract three times with DCM. Dry (sodium sulfate) the solution, filter and concentrate to give 5-methyl-1-pyridin-2-yl-1H-pyrazole-4-carbaldehyde as a white solid (0.496 g, 100%). MS (m/z): 188 (M+1).

1. customat −78° C
2. extractionextract three times with DCM
3. dry with materialDry (sodium sulfate) the solution
4. filtrationfilter
5. concentrationconcentrate