Acetic Acid → 7-methoxy-2-methyl-1H-indole

Participants

Reaction Steps

To a 2 L hydrogenation flask were added 1-(2-Nitro-3-methoxyphenyl)-2-nitropropene (44 g, 0.1850 mol), 10% Pd/C (4.4 g, 50% water wet), EtOAc (600 mL), acetic acid (90 mL) and absolute EtOH (75 mL). The reaction mixture was hydrogenated at <60 psi for 3 h and then filtered. The cake was washed with EtOAc (3×100 mL). The filterate was concentrated to remove EtOAc and EtOH. DI water (200 mL) was then added slowly. The resulting slurry was stirred for 0.5 h at RT and filtered. The cake was washed with 1:2 HOAc/H2O (2×30 mL) 1:4 HOAc/H2O (50 mL), water (2×80 mL) and suction dried for 18 h to give 2-methyl-7-methoxyindole (8.3 g, 62% yield). 1H NMR (CDCl3) δ2.42 (s, 3H), 3.94 (s, 3H), 6.18 (pseudo t, J=1.1 Hz, 1H), 6.57 (d, J=7.7 Hz, 1H), 6.97 (pseudo t, J=7.7 Hz, 1H), 7.12 (d, J=7.7 Hz, 1H), 8.10 (s, 1H).

Provenance & Evidence