反应详情

To a suspension of sodium hydride (containing 63%, 652 mg) in dimethylformamide (abbreviated as DMF hereinafter) was added a solution of 4-ethoxycarbonylpyrazole (2.00 g) in DMF (15 ml) at room temperature. After stirred for 30 min at room temperature, to the mixture was added benzylbromide (2.04 ml). After stirred for 30 min, the mixture was quenched by addition of water. The mixture was extracted with ethyl acetate-n-hexane. The extract was washed with a saturated aqueous solution of sodium chloride, dried over anhydrous magnesium sulfate, and evaporated. The residue was purified by silica gel column chromatography (n-hexane:ethyl acetate=3:1) to give the title compound (2.98 g) having the following physical data.

1. stirringAfter stirred for 30 min
2. customthe mixture was quenched by addition of water
3. extractionThe mixture was extracted with ethyl acetate-n-hexane
4. washThe extract was washed with a saturated aqueous solution of sodium chloride
5. dry with materialdried over anhydrous magnesium sulfate
6. customevaporated
7. customThe residue was purified by silica gel column chromatography (n-hexane:ethyl acetate=3:1)