L-Proline, ethyl ester → (S)-ethyl 1-(5-bromo-3-nitropyridin-2-yl)pyrrolidine-2-carboxylate
Reaction equation
[Br:1][C:2]1[CH:3]=[C:4]([N+:9]([O-:11])=[O:10])[C:5](Cl)=[N:6][CH:7]=1.[NH:12]1[CH2:16][CH2:15][CH2:14][C@H:13]1[C:17]([O:19][CH2:20][CH3:21])=[O:18]>>[Br:1][C:2]1[CH:3]=[C:4]([N+:9]([O-:11])=[O:10])[C:5]([N:12]2[CH2:16][CH2:15][CH2:14][C@H:13]2[C:17]([O:19][CH2:20][CH3:21])=[O:18])=[N:6][CH:7]=1Participants
3
Conditions
- Temperature
- 90 °C
Procedure
5-bromo-2-chloro-3-nitropyridine (5.94 g, 25 mmol) and (S)-ethyl pyrrolidine-2-carboxylate (7.52 g, 52.5 mmol) were combined and stirred at 90° C. for 10 min in a closed vial. The crude material was purified by flash column chromatography (20-30% EtOAc in hexanes to afford (S)-ethyl 1-(5-bromo-3-nitropyridin-2-yl)pyrrolidine-2-carboxylate (8.43 g, 24.49 mmol, 98% yield) as a yellow viscous oil. [M+H] calc'd for C12H14BrN3O4, 344; found, 344.