反应详情

Add slowly and dropwise a solution of allylmagnesium bromide (2.0 M in THF, 100.3 mL, 200.5 mmol) to a stirred solution of (S)-3-(methoxy(methyl)carbamoyl)-pyrrolidine-1-carboxylic acid tert-butyl ester (37.0 g, 143.2 mmol) in THF (296 mL) kept under nitrogen at 0° C. Allow the reaction to warm to room temperature and continue to stir for 48 hours. Add the mixture over a cold solution (0-5° C.) of sodium borohydride (5.42 g, 143 mmol) and tertabutylammonium bromide (0.74 g, 2.39 mmol) in water (74 mL) and stir for 1 hour. Separate the phases and extract the water phase with t-butylmethylether (2×). Combine the organic phases and wash with water and brine. Concentrate and purify the crude residue by silica gel column chromatography eluting with t-butylmethylether/hexanes (3/7 to 7/3) to obtain (3S)-3-(1-hydroxy-but-3-enyl)-pyrrolidine-1-carboxylic acid tert-butyl ester (S-mix) (29 g, 85%). MS (m/z)=186.1 [M−55].

1. additionAdd slowly
2. customkept under nitrogen at 0° C
3. customthe reaction
4. stirringstir for 1 hour
5. customSeparate the phases
6. extractionextract the water phase with t-butylmethylether (2×)
7. washCombine the organic phases and wash with water and brine
8. concentrationConcentrate
9. custompurify the crude residue by silica gel column chromatography
10. washeluting with t-butylmethylether/hexanes (3/7 to 7/3)