反应详情

温度

0 °C

A stirred suspension of 95% sodium hydride (60.8 g, 2.532 mol) in anhydrous dimethylformamide (500 ml) under an atmosphere of argon was cooled to 0° C. (ice bath). A solution of diethyl acetamidomalonate (500 g, 2.302 mol) in anhydrous dimethylformamide (1.2 l) was added over a period of 45 minutes while keeping the reaction temperature below 18° C. After the addition was complete, the turbid solution was gradually warmed to room temperature. After stirring for one hour at room temperature, 4-bromobutyl acetate (471.5 g, 2.417 mol) was added. The mixture was then stirred at 59°-60° C. for 18 hours. The resulting slurry was cooled to room temperature, quenched with absolute ethanol (40 ml) and glacial acetic acid (4 ml), stirred for about 15 minutes, poured into a 10% lithium chloride solution and extracted with ethyl acetate (2×3 l). The combined ethyl acetate extracts were washed with 10% lithium chloride (3×3 l), dried (anhydrous sodium sulfate), and evaporated in vacuo to give 750 g of title product as an oil.

1. customthe reaction temperature below 18° C
2. additionAfter the addition
3. temperaturethe turbid solution was gradually warmed to room temperature
4. stirringThe mixture was then stirred at 59°-60° C. for 18 hours
5. temperatureThe resulting slurry was cooled to room temperature
6. customquenched with absolute ethanol (40 ml) and glacial acetic acid (4 ml)
7. stirringstirred for about 15 minutes
8. additionpoured into a 10% lithium chloride solution
9. extractionextracted with ethyl acetate (2×3 l)
10. washThe combined ethyl acetate extracts were washed with 10% lithium chloride (3×3 l)
11. dry with materialdried (anhydrous sodium sulfate)
12. customevaporated in vacuo