Methyl iodide → 4-Bromo-1-methyl-1H-indole

Participants

Reaction Steps

A solution of 4-bromoindole (5 g, TCI) in DMF (30 ml) was added with 60% sodium hydride (1.14 g) under ice cooling and stirred for 10 minutes. The mixture was added dropwise with methyl iodide (3.18 ml, TCI), stirred for 10 minutes, then warmed to room temperature and further stirred for 30 minutes. The reaction mixture was poured into ice water and added with ethyl acetate (300 ml) for extraction. The organic layer was washed successively with saturated aqueous sodium hydrogencarbonate, saturated aqueous ammonium chloride and saturated brine and dried, and then the solvent was evaporated under reduced pressure. The residue was purified by column chromatography (Quad, hexane:ethyl acetate=10:1) to obtain the title compound (Intermediate 51, 4.95 g).

Provenance & Evidence