反应详情

温度

-20 °C

A solution of methyl 2-cyanoacetate (30 mL, 340 mmol) in DMF (26 mL) and DBU (112 mL, 748 mmol) was heated to 50° C. for 15 min and then cooled to −20° C. To this stirred solution was added dibromobutane 18. The internal temperature increased to 70° C. during the addition. The reaction was set aside to cool to rt before quenching with H2O (800 mL). The product was extracted with Et2O (3×300 mL). The ether layer was washed with 1N HCl (400 mL) and H2O (400 mL). The combined extracts were dried over magnesium sulfate, and concentrated to a crude oil that was distilled under high vacuum at 80° C. to yield the desired product in 58% yield.

1. temperatureThe internal temperature increased to 70° C. during the addition
2. temperatureto cool to rt
3. custombefore quenching with H2O (800 mL)
4. extractionThe product was extracted with Et2O (3×300 mL)
5. washThe ether layer was washed with 1N HCl (400 mL) and H2O (400 mL)
6. dry with materialThe combined extracts were dried over magnesium sulfate
7. concentrationconcentrated to a crude oil that
8. distillationwas distilled under high vacuum at 80° C.