Potassium Hydroxide → 2-Ethyl-6-methoxy-1-methyl-1H-indole-3-carboxylic acid

Participants

Reaction Steps

KOH (1.9 g, 33.49 mmole) in 20 ml H2O was added to a solution of 1-(2-ethyl-6-methoxy-1-methyl-1H-indol-3-yl)-2,2,2-trifluoro-ethanone 73d (2.42 g, 8.47 mmole) in 20 ml EtOH. The reaction mixture was heated to reflux for 8 h and concentrated. The residue was dissolved in H2O acidified with 1N HCl to pH ˜1 and filtrated. The solid was purified by flash column chromatography (2-5% CH3OH in CH2Cl2) to give yellow color solid (1.3 g, 72%). 1H NMR (CDCl3) δ11.88 (1H, bs), 7.82 (1H, d, J=8.7 Hz), 7.04 (1H, s), 6.77 (1H, d, J=8.7 Hz), 3.80 (3H, s), 3.70 (3H, s), 3.51 (2H, q, J=7.4 Hz), 1.15 (3H, t, J=7.4 Hz). ESIMS (MH+): 234.05.

Provenance & Evidence