反应 #2171053

反应方程式

DMF

sodium hydride

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

benzenesulfonyl chloride

→

titled compound

收率 87.0%

4-(1-Benzenesulfonyl-5-chloroindol-3-yl)-2-hydroxy-4-oxo-2-butenoic acid ethyl ester

收率 87.0%

溶剂

THF

THF

反应条件

后处理

1. 1
   workup.ADDITIONwas added under ice-
2. 2
   温度cooling
3. 3
   workup.STIRRINGAfter stirring for 2 hours at room temperature, to the mixture
4. 4
   workup.STIRRINGAfter stirring for additional 30 min
5. 5
   萃取extracted with ethyl acetate
6. 6
   洗涤The organic layer was washed with water and saturated brine
7. 7
   其他dried
8. 8
   浓缩The solvent was concentrated
9. 9
   其他the residue was crystallized from ether
10. 10
    其他to give crude crystal, which
11. 11
    洗涤was washed with ether

实验过程

To a suspension of 0.88 g (22 mmol) of sodium hydride (60% dispersion in mineral oil) in THF (50 ml) was added under ice-cooling, 2.94 g (10 mmol) of 4-(5-chloroindol-3-yl)-2-hydroxy-4-oxo-2-butenoic acid ethyl ester prepared in Example 1 (1). After stirring for 15 min at room temperature, to the mixture was added dropwise a solution of 2.12 g (12 mmol) of benzenesulfonyl chloride in THF (20 ml). After stirring for 2 hours at room temperature, to the mixture was added DMF (8 ml). After stirring for additional 30 min, the reaction mixture was poured into ice-water containing 1N hydrochloric acid, and extracted with ethyl acetate. The organic layer was washed with water and saturated brine, and then dried. The solvent was concentrated and the residue was crystallized from ether to give crude crystal, which was washed with ether to give 3.75 g of the titled compound. Yield: 87%. Subsequent recrystallization from ethyl acetate afforded the pure ester, melted at. 156-157° C.

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