Bromide ion → 3-Bromo-1h-indole

Participants

Reaction Steps

To a solution of the above bromide (1.09 g, 2.8 mmol) was added 4,4′-dimethoxybenzhydrol (818 mg, 3.4 mmol) and p-toluenesulfonic acid (532 mg, 2.8 mmol) in benzene (60 mL) and N-methylpyrrolidinone (6 mL) were heated to reflux. After 24 h the reaction was allowed to cool to room temperature and diluted with ethyl acetate (200 mL). The organic layer was washed with NaHCO3 (2×), H2O (2×), and Brine(2×), dried over anhydrous MgSO4, filtered and the solvent removed in vacuo. The crude material was purified via column chromatography (10% EtOAc-Hexane) to provide the desired DMB protected 3-bromoindole derivative (1.5 g, 2.4 mmol, 87% yield) as an orange solid: (ESII-MS (M+H) 616.5 m/e).

Provenance & Evidence