Bromine → 5-bromo-1-methyl-2-oxo-2,3-dihydro-1H-indole-6-carbonitrile

Participants

Reaction Conditions

Reaction Steps

Water (9 mL) was added to 1-methyl-2-oxo-2,3-dihydro-1H-indole-6-carbonitrile (110 mg 0.64 mmol) and the resulting mixture was placed at 70° C. In a separate flask potassium bromide (462 g, 0.26 mmol) in water (12 mL) was treated with bromine (0.100 mL, 1.94 mmol). 6.0 mL of the orange bromine solution was added dropwise to the water and 1-methyl-2-oxo-2,3-dihydro-1H-indole-6-carbonitrile mixture over ca. 20 minutes. The resulting heterogeneous mixture was permitted to stir at 70° C. for an additional 5 minutes and then cooled to room temperature. The reaction was then diluted with dichloromethane and saturated aqueous sodium bicarbonate. The solution was then further diluted with saturated aqueous sodium thiosulfate. The layers were separated and the aqueous layer was extracted two additional times with dichloromethane. The organic extracts were combined, dried over anhydrous sodium sulfate, filtered and concentrated. The resulting residue was purified by silica gel flash chromatography (ethanol-dichloromethane 0 to 3.5%) to provide 5-bromo-1-methyl-2-oxo-2,3-dihydro-1H-indole-6-carbonitrile; MS: (ES+) m/z 250.9 (M+H)+.

Provenance & Evidence