反应详情

温度

70 °C

The crude, wet product of Example 3a was slurried in 1N HCl (192 mL) and the slurry was heated to 70° C. with stirring. After 1 hour, THF (100 mL) was added and stirring at 65° C. was continued for 4 hours. The mixture was then allowed to cool to 20–25° C. and was stirred overnight at 20–25° C. The THF was removed by evaporation under vacuum and the resulting aqueous solution was cooled to about 5° C., causing some precipitation to occur. The aqueous mixture was adjusted to pH 7 by addition of 50% aqueous sodium hydroxide (about 18.3 g). The resulting mixture was extracted with ethyl acetate (2×100 mL) at about 15° C. The combined organic extracts were washed with 100 mL of brine and the organic layer was separated and stirred with sodium sulfate (5 g) and Darco G-60 (3 g). This mixture was warmed on a hot plate for 1 hour at 45° C. The hot mixture was then filtered through a bed of diatomaceous earth and the filter pad was washed with ethyl acetate (100 mL). The filtrate was evaporated under vacuum to provide an oil. The oil was redissolved in methylene chloride (300 mL) and the solvent was evaporated under vacuum. The resulting oil was dried at room temperature under vacuum to provide the desired product (18.4 g) as a glassy syrup.

1. stirringstirring at 65° C.
2. waitwas continued for 4 hours
3. temperatureto cool to 20–25° C.
4. stirringwas stirred overnight at 20–25° C
5. customThe THF was removed by evaporation under vacuum
6. temperaturethe resulting aqueous solution was cooled to about 5° C.
7. customsome precipitation
8. additionThe aqueous mixture was adjusted to pH 7 by addition of 50% aqueous sodium hydroxide (about 18.3 g)
9. extractionThe resulting mixture was extracted with ethyl acetate (2×100 mL) at about 15° C
10. washThe combined organic extracts were washed with 100 mL of brine
11. customthe organic layer was separated
12. stirringstirred with sodium sulfate (5 g) and Darco
13. temperatureThis mixture was warmed on a hot plate for 1 hour at 45° C
14. filtrationThe hot mixture was then filtered through a bed of diatomaceous earth
15. washthe filter pad was washed with ethyl acetate (100 mL)
16. customThe filtrate was evaporated under vacuum
17. customto provide an oil
18. customthe solvent was evaporated under vacuum
19. customThe resulting oil was dried at room temperature under vacuum