反应详情

温度

0 °C

A solution of ethyl ester 7b (80.0 mg, 0.198 mmol) in THF (1.5 mL) was cooled to 0° C. and 1 M LiOH (1.00 mL, 1.00 mmol) was added. The mixture was stirred for 20 h during which time the temperature reached rt after 1.5 h. The THF was removed in vacuo and the remaining aqueous solution was diluted with deionized H2O to a final volume of 3 mL. The aqueous mixture was extracted with Et2O (3×) and cooled to 0° C. 2 M HCl was added obtain pH=3. The mixture was extracted with EtOAc (3×) and the combined EtOAc portions were washed with brine, dried over MgSO4 and filtered through a Celite plug capped with a layer of MgSO4. The EtOAc solution was concentrated to give the title acid 8b as bronze foam scraped to beige solid; 62 mg, 83%, MS m/z 375.1 (ESI−, M−1).

1. waitreached rt after 1.5 h
2. customThe THF was removed in vacuo
3. additionthe remaining aqueous solution was diluted with deionized H2O to a final volume of 3 mL
4. extractionThe aqueous mixture was extracted with Et2O (3×)
5. addition2 M HCl was added
6. customobtain pH=3
7. extractionThe mixture was extracted with EtOAc (3×)
8. washthe combined EtOAc portions were washed with brine
9. dry with materialdried over MgSO4
10. filtrationfiltered through a Celite plug
11. customcapped with a layer of MgSO4
12. concentrationThe EtOAc solution was concentrated