反应详情

A flask was loaded with 47% HBr (12 ml), water (6 ml), and compound 26 (6 g), and then was heated to reflux for 3 hours. The solution was cooled to room temperature, and water (12 ml) was added. An aqueous 47% sodium hydroxide solution was added to obtain pH of 3. The solution was then extracted twice with isobutanol (15 ml), the combined organic layers were evaporated and fresh isobutanol was added (15 ml). Bu3N (3.8 g) was added. The mixture was cooled to 2° C. for 1 hour, then (S)-Pregabalin was filtered, and washed with of iso-butanol (3 ml). After drying at 55° C. under vacuum, (S)-Pregabalin was obtained as white crystals in a 90% yield.

1. temperaturewas heated
2. temperatureto reflux for 3 hours
3. customto obtain pH of 3
4. extractionThe solution was then extracted twice with isobutanol (15 ml)
5. customthe combined organic layers were evaporated
6. additionfresh isobutanol was added (15 ml)
7. additionBu3N (3.8 g) was added
8. temperatureThe mixture was cooled to 2° C. for 1 hour
9. filtration(S)-Pregabalin was filtered
10. washwashed with of iso-butanol (3 ml)
11. customAfter drying at 55° C. under vacuum