反应详情

Lithium bis(trimethylsilyl)amide (100 mL, 100 mmol) was added dropwise over 1 hour to a solution of 4-picoline (4.6 g, 49.4 mmol) and ethyl 2-furancarboxylate (7.7 g, 54.9 mmol) in tetrahydrofuran (40 mL) at 0° C. in a nitrogen atmosphere, followed by stirring as such for 2 hours. Hexane (140 mL) was added to the reaction solution, and the resulting crystals were collected by filtration. The resulting crystals were dissolved in ethyl acetate and an aqueous saturated ammonium chloride solution. The organic layer was washed with an aqueous saturated ammonium chloride solution (×2) and brine, dried over anhydrous sodium sulfate, and concentrated. Hexane was added to the residue, and the resulting precipitates were collected by filtration and washed with hexane, to give the title compound (6.5 g, 70%) as a pale yellow solid.

1. filtrationthe resulting crystals were collected by filtration
2. dissolutionThe resulting crystals were dissolved in ethyl acetate
3. washThe organic layer was washed with an aqueous saturated ammonium chloride solution (×2) and brine
4. dry with materialdried over anhydrous sodium sulfate
5. concentrationconcentrated
6. additionHexane was added to the residue
7. customthe resulting precipitates
8. filtrationwere collected by filtration
9. washwashed with hexane