[C:1]([O:5][C:6]([C@@:8]1([CH:22]=[CH2:23])[CH2:12][C:11](=[O:13])[N:10]([C@@H:14]([C:16]2[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=2)[CH3:15])[CH2:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2].[CH2:24](Br)[CH:25]=[CH2:26].C[Si](C)(C)[N-][Si](C)(C)C.[Li+].[Cl-].[NH4+]>O1CCCC1>[C:1]([O:5][C:6]([C@@:8]1([CH:22]=[CH2:23])[C@H:12]([CH2:26][CH:25]=[CH2:24])[C:11](=[O:13])[N:10]([C@@H:14]([C:16]2[CH:17]=[CH:18][CH:19]=[CH:20][CH:21]=2)[CH3:15])[CH2:9]1)=[O:7])([CH3:4])([CH3:2])[CH3:3](3R)-5-oxo-1-[(1R)-1-phenylethyl]-3-vinylpyrrolidine-3-carboxylic acid tert-butyl ester (236.0 mg, 0.75 mmol) and allyl bromide (271.6 mg, 2.24 mmol) were dissolved in tetrahydrofuran. A 1 M solution of lithium hexamethyldisilazide in tetrahydrofuran (1.12 mL, 1.12 mmol) was added dropwise in a nitrogen atmosphere at 0° C. After stirring for 1.5 hours, a saturated ammonium chloride solution was added, followed by extraction with ethyl acetate. The organic layer was washed with water and brine, dried over anhydrous sodium sulfate, and filtered. The solvent was evaporated under reduced pressure, and the resulting residue was subjected to silica gel column chromatography (10% ethyl acetate/hexane) to give 135 mg of the title compound as a colorless oil.
Loading…