Dimethylformamide → methyl 1H-indole-4-carboxylate

Participants

Reaction Steps

To a 100 mL round bottomed flask was added, indole-5-carboxylic acid (3.57 g, 22.2 mmol), powdered sodium hydrogen carbonate (5.95 g, 70.83 mmol), methyl iodide (5.95 mL, 95.6 mmol) and DMF (25 mL). The mixture was stirred for 72 h under an atmosphere of nitrogen, whereupon water (20 mL) and ethyl acetate (40 mL) was added. The phases were then partitioned and the aqueous phase extracted with ethyl acetate (40 mL). The combined organics were washed with aqueous sodium hydrogen carbonate, dried (sodium sulfate) and concentrated to furnish a white solid (3.88 g, 99%). 1H NMR (400 MHz, Acetone d6, δ in ppm) 10.61 (br s, 1H), 8.38 (s, 1H), 7.81 (dd, J=8.6 and 1.5 Hz), 7.51 (1 H, d, J=8.6 Hz), 7.46 (m, 1H), 6.65-6.63 (1H, m) and 3.87 (3H, s).

Provenance & Evidence