反应详情

Allyl bromide (1.36 mL, 16.1 mmol) was added to a solution of (3S)-3-allyl-5-oxo-1-[(1R)-1-phenylethyl]pyrrolidine-3-carboxylic acid tert-butyl ester (4.05 g, 12.3 mmol) in tetrahydrofuran (41.0 mL) with stirring under salt ice cooling. A 1 M solution of lithium hexamethyldisilazide in tetrahydrofuran (16.0 mL, 16.0 mmol) was added dropwise with stirring under salt ice cooling, and the mixture was stirred under salt ice cooling for 15 minutes. A saturated ammonium chloride solution (40 mL) and water (20 mL) were added to the reaction solution, followed by extraction with ethyl acetate (40 mL×1, 20 mL×1). The organic layer was washed with brine (140 mL) and dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate=100:0→90:10→89:11→88:12→87:13→83:17→80:20→75:25) to give 2.02 g of the title compound.

1. stirringwith stirring under salt ice cooling
2. stirringthe mixture was stirred under salt ice cooling for 15 minutes
3. extractionfollowed by extraction with ethyl acetate (40 mL×1, 20 mL×1)
4. washThe organic layer was washed with brine (140 mL)
5. dry with materialdried over anhydrous sodium sulfate
6. filtrationAfter filtration
7. concentrationthe filtrate was concentrated under reduced pressure
8. customThe resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate=100:0→90:10→89:11→88:12→87:13→83:17→80:20→75:25)