反应详情

温度

0 °C

A 3-L, three-necked, round bottomed flask fitted with a nitrogen inlet, overhead stirrer, and thermocouple was charged with (S)-N-(5-bromo-2-(1-hydroxypropan-2-ylamino)phenyl)-4-methylbenzenesulfonamide (77.0 g, 193 mmol), THF (1925 mL), and triphenylphosphine (60.7 g, 231 mmol). The solution was cooled to 0° C., and diisopropyl azodicarboxylate (DIAD) (41.2 mL, 212 mmol) was slowly added while maintaining the internal temperature below 7° C. The reaction mixture stirred at 0° C. for 1.5 h and was then warmed to room temperature. The mixture was concentrated and the residue was purified by column chromatography on silica gel (eluting with dichloromethane). The product-containing fraction were combined and concentrated under reduced pressure. The material was treated with a mixture of 4:1 hexanes-dichloromethane, and the slurry was stirred for 3 h and then filtered. The solids were rinsed with cold (ca. 0° C.) solution of 4:1 hexanes-dichloromethane (50 mL) and dried to afford (S)-7-bromo-3-methyl-1-tosyl-1,2,3,4-tetrahydroquinoxaline (61.8 g, 84%) as a white solid. MS (ESI, pos. ion) m/z 381 [M+1]+.

1. temperaturewhile maintaining the internal temperature below 7° C
2. temperaturewas then warmed to room temperature
3. concentrationThe mixture was concentrated
4. customthe residue was purified by column chromatography on silica gel (eluting with dichloromethane)
5. concentrationconcentrated under reduced pressure
6. additionThe material was treated with a mixture of 4:1 hexanes-dichloromethane
7. stirringthe slurry was stirred for 3 h
8. filtrationfiltered
9. washThe solids were rinsed with cold (ca. 0° C.) solution of 4:1 hexanes-dichloromethane (50 mL)
10. customdried