Ammonia → tert-butyl 7-carbamoyl-1H-indole-4-carboxylate

Participants

Reaction Steps

A solution of 4-(tert-butoxycarbonyl)-1H-indole-7-carboxylic acid (0.36 g, 1.38 mmol), HATU (0.30 g, 1.60 mmol), 4-methylmorpholine (0.75 mL, 6.89 mmol) and a 2M solution of ammonia in methanol (1.80 mL, 3.45 mmol) in dimethylformamide (5 mL) was stirred at room temperature for 18 hours. The reaction mixture was diluted with ethyl acetate (150 mL) and the organic layer was washed with brine, dried over sodium sulfate, filtered and concentrated. Purification by column chromatography chloroform: (10% ammonium hydroxide in methanol) 9:1 as eluent afforded tert-butyl 7-carbamoyl-1H-indole-4-carboxylate (0.18 g, 50%). 1H NMR (400 MHz, CDCl3): 10.50 (bs, 1H), 7.83 (d, 1H), 7.43 (m, 2H), 7.15 (m, 1H), 6.30 (bd, 2H), 1.62 (s, 9H). MS (EI) for C14H16N2O3: 259 (M−H).

Provenance & Evidence