反应详情

A mixture of 2,3-dihydro-1-(1-oxo-2-propenyl)-1H-indole-2-carboxylic acid ethyl ester (14.4 g.), 80% aqueous dimethyl-sulfoxide (200 ml.) and potassium hydroxide (86% pellets, 3.83 g.) was stirred under nitrogen atmosphere for 2.5 days at room temperature, then evaporated under reduced pressure on a rotary evaporator to give an oily residue. The residue was dissolved in water with the aide of a small amount of dilute sodium hydroxide solution. The aqueous solution was washed with ether twice, then made acidic by addition of dilute hydrochloric acid to pH ca. 2. The oil thus separated was extracted with ether three times. The combined ether extract was washed with water, then with saline, and dried over anhydrous magnesium sulfate. Evaporation of the ether on a rotary evaporator under reduced pressure gave a solid residue which melted at 158°-160°, and weighed 9.2 g. Recrystallization from ethyl acetate improved the melting point to 167°-169°.

1. customevaporated under reduced pressure on a rotary evaporator
2. customto give an oily residue
3. washThe aqueous solution was washed with ether twice
4. additionmade acidic by addition of dilute hydrochloric acid to pH ca. 2
5. customThe oil thus separated
6. extractionwas extracted with ether three times
7. extractionThe combined ether extract
8. washwas washed with water
9. dry with materialwith saline, and dried over anhydrous magnesium sulfate
10. customEvaporation of the ether
11. customon a rotary evaporator under reduced pressure
12. customgave a solid residue which melted at 158°-160°
13. customRecrystallization from ethyl acetate
14. customto 167°-169°