反应详情

温度

25 °C

To a solution of ethyl 2-oxocyclopentanecarboxylate (5.00 mL, 32.1 mmol) in ethanol (50 mL) was added isoamylamine (3.8 mL, 32.3 mmol) at 25° C. The mixture was heated at reflux for 12 h. The reaction mixture was allowed to cool to 25° C. and concentrated in vacuo. The crude material was purified by flash column chromatography (Teledyne Isco RediSep Flash Column; 0-30% ethyl acetate in hexanes) to afford the desired product, 2-(3-methylbutylamino)-cyclopent-1-enecarboxylic acid ethyl ester (6.84 g, 30.4 mmol, 95%), as a yellowish oil. 1H NMR (400 MHz, CDCl3) δ 0.92 (6H, d, J=6.1 Hz), 1.28 (3H, t, J=6.9 Hz), 1.44 (2H, q, J=7.2 Hz), 1.63-1.74 (1H, m), 1.80-1.87 (2H, m), 2.50-2.58 (4H, m), 3.19 (2H, q, J=6.7 Hz), 4.14 (2H, q, J=7.1 Hz), 7.34 (1H, bs).

1. temperatureThe mixture was heated
2. temperatureat reflux for 12 h
3. concentrationconcentrated in vacuo
4. customThe crude material was purified by flash column chromatography (Teledyne Isco RediSep Flash Column; 0-30% ethyl acetate in hexanes)