反应详情

A mixture of (E)-ethyl 5-(2-(dimethylamino)vinyl)-2,4-dinitrobenzoate (15 g, 0.050 mol) and Raney Nickel (5 g) in EtOH (500 mL) was hydrogenated at room temperature under 50 psi of hydrogen for 2 h. The catalyst was filtered off and the filtrate was concentrated to dryness. The residue was purified by column on silica gel to give ethyl 6-amino-1H-indole-5-carboxylate (3.0 g, 30%). 1H NMR (DMSO-d6) δ 10.68 (s, 1H), 7.99 (s, 1H), 7.01-7.06 (m, 1H), 6.62 (s, 1H), 6.27-6.28 (m, 1H), 6.16 (s, 2H), 4.22 (q, J=7.2 Hz, 2H), 1.32-1.27 (t, J=7.2 Hz, 3H).

1. filtrationThe catalyst was filtered off
2. concentrationthe filtrate was concentrated to dryness
3. customThe residue was purified by column on silica gel