反应详情

To an ethanol solution of sodium ethoxide which had been synthesized by adding 5.8 g of metallic sodium to 300 ml of ethanol, 62.2 g of ethyl N-ethoxycarbonylacetyl-3-ethylaminopropionate (Referential Example 34) was added. The resultant mixture was refluxed for 4 hours. After allowing the reaction mixture to cool down, ethanol was distilled off. Ethyl acetate and a dilute aqueous solution of hydrogen chloride were added. The resulting mixture was shaken. After washing the organic layer with water, it was dried and concentrated to obtain 36.3 g of 3-carboethoxy-1-ethylpiperidine-2,4-dione as an oily substance (yield: 71%).

1. additionwas added
2. temperatureto cool down
3. distillationethanol was distilled off
4. additionEthyl acetate and a dilute aqueous solution of hydrogen chloride were added
5. washAfter washing the organic layer with water, it
6. customwas dried
7. concentrationconcentrated