反应 #2171052

反应方程式

diethyl oxalate

sodium

3-acetyl-5-chloroindole

→

titled compound

收率 81.0%

4-(5-Chloroindol-3-yl)-2-hydroxy-4-oxo-2-butenoic acid ethyl ester

收率 81.0%

溶剂

EtOH

反应条件

后处理

1. 1
   温度under heating
2. 2
   其他The EtOH was evaporated under reduced pressure
3. 3
   其他The THF was evaporated
4. 4
   workup.ADDITIONTo the suspension of the residue in THF (124 ml)
5. 5
   workup.ADDITIONSubsequently, to the above suspension was added at room temperature
6. 6
   workup.STIRRINGthe mixture was stirred at 50° C. for additional 16 hours
7. 7
   其他The solvent was removed under reduced pressure
8. 8
   洗涤The resulting residue was washed with ether
9. 9
   workup.ADDITIONadded to 1N hydrochloric acid (120 ml)
10. 10
    过滤The precipitated crystal was collected by filtration
11. 11
    洗涤washed with water and ethyl acetate
12. 12
    其他Then the crystal was purified by recrystallization from dioxane
13. 13
    其他dried at 80° C. under reduced pressure

实验过程

In 100 ml of EtOH was dissolved 2.99 g (126 mmol) of sodium under heating. The EtOH was evaporated under reduced pressure and the residue was suspended in THF (200 ml). The THF was evaporated. To the suspension of the residue in THF (124 ml) was added 18.1 g (124 mmol) of diethyl oxalate. Subsequently, to the above suspension was added at room temperature, 12 g (62 mmol) of 3-acetyl-5-chloroindole. After stirring for 3 hours, the mixture was stirred at 50° C. for additional 16 hours. The solvent was removed under reduced pressure. The resulting residue was washed with ether, and added to 1N hydrochloric acid (120 ml). The precipitated crystal was collected by filtration, and washed with water and ethyl acetate. Then the crystal was purified by recrystallization from dioxane and dried at 80° C. under reduced pressure to give 14.7 g of the titled compound. Yield: 81%.

来源