反应详情

A 100-mL single-neck round-bottomed flask equipped with a magnetic stirrer and nitrogen inlet was purged with nitrogen and charged with 101a (6.50 g, 24.8 mmol), sodium ethoxide (17.0 mg, 0.25 mmol) and ethanol (40 mL). The solution was stirred at room temperature for 1 h. After that time, the reaction mixture was concentrated under reduced pressure. The residue was purified by column chromatography to afford a 100% yield (4.80 g) of ethyl 4,5,6,7-tetrahydro-1H-indole-2-carboxylate 101b as a brown solid: mp 70-72° C.; 1H NMR (300 MHz, CDCl3) δ 9.08 (s, 1H), 6.75 (s, 1H), 4.25 (q, 2H, J=7.2 Hz), 2.65 (t, 2H, J=6.0 Hz), 2.56 (t, 2H, J=6.0 Hz), 1.85 (m, 4H), 1.28 (t, 3H, J=7.2 Hz); MS (ESI+) m/z 194.1 (M+H)

1. customA 100-mL single-neck round-bottomed flask equipped with a magnetic stirrer and nitrogen inlet
2. customwas purged with nitrogen
3. concentrationAfter that time, the reaction mixture was concentrated under reduced pressure
4. customThe residue was purified by column chromatography