2-Bromopropene → tert-butyl ((2S)-4-methyl-3-oxo-1-(2-oxopyrrolidin-3-yl)pent-4-en-2-yl)carbamate

関与物質

反応条件

反応手順

n-BuLi (2.5 M, 3.17 mL, 7.9 mmol) was added dropwise to a solution of isopropenyl bromide (0.9 g, 8.3 mmol) in THF (15.0 mL) at −78° C. and the mixture was stirred at −78° C. for 30 min. A solution of tert-butyl ((2S)-1-(methoxy(methyl)amino)-1-oxo-3-(2-oxopyrrolidin-3-yl) propan-2-yl)carbamate (500 mg, 1.58 mmol) in THF (5.0 mL) was added dropwise. The reaction mixture was stirred at −78° C. for 3 h and then allowed to warm to ambient temperature and stirred for 12 h. Saturated aqueous NH4Cl (50 mL) was added and the resulting mixture was extracted with EtOAc (50 mL×2). The combined extracts were washed with brine, dried over anhydrous sodium sulfate, and concentrated. The residue was purified by flash column chromatography on silica gel (petroleum ether/EtOAc=20:1) to afford tert-butyl ((2S)-4-methyl-3-oxo-1-(2-oxopyrrolidin-3-yl)pent-4-en-2-yl)carbamate (200 mg, 42% yield) as a yellow oil.

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