tert-butyl N-[(2S)-3-(cyclopenten-1-yl)-1-[methoxy(methyl)amino]-1-oxopropan-2-yl]carbamate → tert-Butyl (S)-(1-(cyclopent-1-en-1-yl)-4-methyl-3-oxopent-4-en-2-yl)carbamate

関与物質

反応条件

反応手順

To a solution of (S)-tert-butyl (3-(cyclopent-1-en-1-yl)-1-(methoxy(methyl)amino)-1-oxopropan-2-yl)carbamate (81 g, 0.27 mol) in THF (600 mL) was added freshly prepared prop-1-en-2-ylmagnesium bromide (96.0 mL, 1.08 mol) at 0° C. dropwise. After completion of the addition, the reaction mixture was stirred at 0° C. for 2 h then quenched with saturated aqueous ammonium chloride (500 mL). The resulting mixture was extracted with EtOAc (400 mL×2). The organic phases were combined, dried over anhydrous sodium sulfate, and concentrated. The residue was purified by flash column chromatography on silica gel (petroleum ether/EtOAc=100:1) to afford (S)-tert-butyl (1-(cyclopent-1-en-1-yl)-4-methyl-3-oxopent-4-en-2-yl)carbamate as colorless oil (39.3 g, 52% yield).

情報源と証拠