反应详情

To a mixture of N-benzyl-3-hydroxypyrrolidine (0.50 g, 2.84 mmol) in dichloromethane (5 mL) and pyridine (0.46 mL, 5.68 mmol) is added benzoyl chloride (0.4 mL, 3.41 mmol) at 0° C., and the mixture is stirred for 1 hour while warming to room temperature. After addition of saturated aqueous NaHCO3, the mixture is extracted with EtOAc. The combined organic layer is dried over MgSO4, filtered, and concentrated. The resulting N-benzyl-3-benzoyloxypyrrolidine is used for next step without further purification. To a crude mixture of N-benzyl-3-benzoyloxypyrrolidine (114 mg, 0.41 mmol) in dichloromethane (1 mL) is added α-chloroethyl chloroformate (57 μL, 0.49 mmol) at 0° C., and the mixture is stirred for 1 hour while warming to room temperature. After removing dichloromethane, resulting mixture is diluted with MeOH. The reaction mixture is heated to 80° C. for 0.5 hour. After cooling to room temperature, solvent is evaporated under reduced pressure to obtain (S)-(−)-3-benzoyloxypyrrolidine which is used for next reaction without further purification.

1. extractionthe mixture is extracted with EtOAc
2. dry with materialThe combined organic layer is dried over MgSO4
3. filtrationfiltered
4. concentrationconcentrated
5. customThe resulting N-benzyl-3-benzoyloxypyrrolidine is used for next step without further purification
6. stirringthe mixture is stirred for 1 hour
7. temperaturewhile warming to room temperature
8. customAfter removing dichloromethane
9. customresulting mixture
10. temperatureThe reaction mixture is heated to 80° C. for 0.5 hour
11. temperatureAfter cooling to room temperature
12. customsolvent is evaporated under reduced pressure