反应详情

温度

0 °C

Into a 100-mL round-bottom flask, was placed a solution of 1-benzyl-4-methyl-1H-pyrazol-5-ol (compound 249.2, 2.0 g, 10.6 mmol) in N,N-dimethylformamide (15 mL). The solution was cooled to 0° C., then sodium hydride (600 mg, 15.00 mmol, 60% dispersion in mineral oil) was added in portions and the resulting mixture was stirred for 10 min at 0° C. Iodomethane (878 μL, 14.1 mmol) was added and the resulting mixture was stirred for 3 h at room temperature, then carefully quenched by drop-wise addition of water (10 mL). The mixture was extracted ethyl acetate (3×40 mL) and the combined organic extracts were washed with brine (3×20 mL), dried (Na2SO4), filtered and concentrated under reduced pressure. The residue was purified by a silica gel chromatography with ethyl acetate/petroleum ether (1:8) as eluent to obtain the title compound as a yellow oil (500 mg, 23%).

1. customInto a 100-mL round-bottom flask, was placed
2. stirringthe resulting mixture was stirred for 3 h at room temperature
3. customcarefully quenched by drop-wise addition of water (10 mL)
4. extractionThe mixture was extracted ethyl acetate (3×40 mL)
5. washthe combined organic extracts were washed with brine (3×20 mL)
6. dry with materialdried (Na2SO4)
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure
9. customThe residue was purified by a silica gel chromatography with ethyl acetate/petroleum ether (1:8) as eluent