Methylamine → 6-Bromo-2,3-dihydro-N-methyl-2-oxo-1H-indole-5-carboxamide

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Reaction Steps

Methylamine (0.75 mL, 2.0 M in tetrahydrofuran) was added to a stirred solution of 6-bromo-2-oxoindoline-5-carboxylic acid (0.246 g, 0.96 mmol), O-(benzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium tetrafluoroborate (0.369 g, 1.15 mmol), 1-hydroxybenzotriazole hydrate (0.176 g, 1.15 mmol), and diisopropylethylamine (0.55 mL, 3.16 mmol) in dry N,N-dimethylformamide (4 mL) under an atmosphere of nitrogen. The resulting mixture was stirred at room temperature for 1.5 h. An aqueous solution of sodium bicarbonate was added and the solvent was evaporated. The resulting residue was purified on a silica gel column using dichloromethane/methanol, (9:1), as the eluent to give 0.125 g (48% yield) of the title compound: 1H NMR (CD3OD, 400 MHz) δ 7.27 (s, 1H), 7.11 (s, 1H), 3.20 (m, 2H), 3.09 (s, 3H); MS (ES) m/z 269 and 271 (M++1).

Provenance & Evidence