反应详情

Octahydro-indole-2-carboxylic acid 11b (5.0 g, 29.5 mmol, purchased from Bachem) was suspended in 200 mL of CHCl3 then cooled in a dry ice/acetone bath. H2SO4 (120 uL/mmol) was added followed by bubbling in excess isobutylene. The mixture was sealed and the ice bath removed. The mixture was stirred at RT for 12 hours. The reaction mixture was carefully unsealed after cooling and concentrated. EtOAc was added and washed with saturated sodium bicarbonate soln, brine, dried over sodium sulfate, then filtered and concentrated to give octahydro-indole-2-carboxylic acid tert-butyl ester 12b (6.65 g, 29.5 mmol, 100%).

1. temperaturethen cooled in a dry ice/acetone bath
2. customby bubbling in excess isobutylene
3. customThe mixture was sealed
4. customthe ice bath removed
5. temperatureafter cooling
6. concentrationconcentrated
7. additionEtOAc was added
8. washwashed with saturated sodium bicarbonate soln
9. dry with materialbrine, dried over sodium sulfate
10. filtrationfiltered
11. concentrationconcentrated