反应详情

温度

0 °C

A suspension of potassium tert-butoxide (0.57 g) in tetrahydrofuran (40 mL) at 0° C. was treated with a mixture of tert-butanol (2.0 mL) and 3-oxopentanoic acid ethyl ester (0.73 mL), and the resulting mixture was stirred at 0° C. for 45 minutes. The mixture was then treated with a solution of 1-(4-bromomethylphenyl)-1H-pyrazole (1.0 g) in tetrahydrofuran (10 mL), and stirred at 0° C. for 2 hours. The mixture was diluted with water, concentrated to low bulk under reduced pressure, and the residue extracted with ethyl acetate. The combined extracts were washed with saturated aqueous sodium chloride solution, dried over magnesium sulfate and then concentrated under reduced pressure. Purification of the residue by column chromatography on silica gel, eluting with a mixture of cyclohexane and ethyl acetate gave title compound as a pale yellow oil (0.63 g).

1. stirringstirred at 0° C. for 2 hours
2. concentrationconcentrated to low bulk under reduced pressure
3. extractionthe residue extracted with ethyl acetate
4. washThe combined extracts were washed with saturated aqueous sodium chloride solution
5. dry with materialdried over magnesium sulfate
6. concentrationconcentrated under reduced pressure
7. customPurification of the residue by column chromatography on silica gel
8. washeluting with a mixture of cyclohexane and ethyl acetate