反应详情

温度

5 °C

1.35 g (2.5 mmole) of the compound of Example 3 was dissolved in 50 ml of 50% ethanol-tetrahydrofuran in a 250 ml single neck round bottom flask equipped with a magnetic stirring bar. The contents of the flask were cooled to 5° C. in an ice bath and 25 ml of 0.2N sodium hydroxide solution was added. The reaction mixture was stirred at room temperature for eight hours. Most of the solvent was removed by rotoevaporation, 50 ml of water was added and the aqueous mixture acidified with dilute hydrochloric acid. The acidified solution was extracted three times with 150 ml portions of ethyl acetate and the combined extract washed once with brine. The ethyl acetate extract was dried over anhydrous magnesium sulfate, filtered, and the ethyl acetate removed by rotoevaporation to give 1.19 g (93%) of the title compound as a white solid, mp. 166°-168° C. Calc: C, 67.95; H, 7.08, Found: C, 67.79; H, 7.04.

1. customequipped with a magnetic stirring bar
2. customMost of the solvent was removed by rotoevaporation, 50 ml of water
3. additionwas added
4. extractionThe acidified solution was extracted three times with 150 ml portions of ethyl acetate
5. extractionthe combined extract
6. washwashed once with brine
7. extractionThe ethyl acetate extract
8. dry with materialwas dried over anhydrous magnesium sulfate
9. filtrationfiltered
10. customthe ethyl acetate removed by rotoevaporation