反应详情

A suspension of 19.5 g. of 1-ethoxycarbonyl-5-chloro-3-phenylisoindole-2-acetic acid ethyl ester in 150 ml. of ethanol is treated with 60 ml. of 1.0-N sodium hydroxide and boiled at reflux for 30 minutes. After allowing the mixture to stand for 2 hours in an ice-bath, the crystallized sodium salt is removed by filtration under vacuum, washed with ethanol and then dissolved in a mixture of 400 ml. of ethanol and 250 ml. of water. The obtained solution is acidified with 160 ml. of 0.5-N hydrochloric acid with stirring at 40°-45° C. and then left to stand in an ice-bath for 2 hours. The separated acid is removed by filtration under vacuum, washed with water and then dissolved in 750 ml. of methylene chloride. The aqueous layer is separated, the organic phase dried over sodium sulfate and concentrated to about 200 ml. Then, the crystallized colorless acid is removed by filtration under suction and washed with a small amount of methylene chloride, and there is obtained 1-ethoxycarbonyl-5-chloro-3-phenylisoindole-2-acetic acid; melting point 217°-220° C. (decomposition).

1. additionA suspension of 19.5 g
2. temperatureat reflux for 30 minutes
3. customthe crystallized sodium salt is removed by filtration under vacuum
4. washwashed with ethanol
5. dissolutiondissolved in a mixture of 400 ml
6. waitleft
7. waitto stand in an ice-bath for 2 hours
8. customThe separated acid is removed by filtration under vacuum
9. washwashed with water
10. dissolutiondissolved in 750 ml
11. customThe aqueous layer is separated
12. dry with materialthe organic phase dried over sodium sulfate
13. concentrationconcentrated to about 200 ml
14. customThen, the crystallized colorless acid is removed by filtration under suction
15. washwashed with a small amount of methylene chloride