反应详情

To a deoxygenated solution of methyl 4-(2-butyramido-5-nitrophenyl)-2,2-dimethylbut-3-ynoate (1.8 g, 5.4 mmol) in acetonitrile (30 mL) was added Pd(CH3CN)2Cl2 (0.42 g, 1.6=mmol) under N2. The mixture was heated at reflux for 24 h. After cooling the mixture to ambient temperature, the solid was filtered off and washed with EtOAc (50 mL×3). The filtrate was evaporated under reduced pressure to give a residue, which was purified by column chromatography on silica gel (petroleum ether/ethyl acetate=30/1) to give methyl 2-methyl-2-(5-nitro-1H-indol-2-yl)propanoate (320 mg, 23%). 1H NMR (400 MHz, CDCl3) δ 9.05 (brs, 1H), 8.52 (d, J=2.0 Hz, 1H), 8.09 (dd, J=2.0, 8.8 Hz, 1H), 7.37 (d, J=8.8 Hz, 1H), 6.54 (d, J=1.6 Hz, 1H), 3.78 (d, J=9.6 Hz, 3H), 1.70 (s, 6H).

1. temperatureThe mixture was heated
2. temperatureat reflux for 24 h
3. filtrationthe solid was filtered off
4. washwashed with EtOAc (50 mL×3)
5. customThe filtrate was evaporated under reduced pressure
6. customto give a residue, which
7. customwas purified by column chromatography on silica gel (petroleum ether/ethyl acetate=30/1)