Iodine → 3-Iodo-5-methoxy-1-methyl-1H-indole

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Reaction Steps

A flask containing 5-methoxy-1H-indole (5.15 g, 35.0 mmol) in DMF (100 mL) at rt was stirred with KOH (2.06 g, 36.7 mmol) for about 15 min and then treated with iodine (9.06 g, 35.7 mmol). After about 30 min, 60 wt % NaH (1.68 g, 42.0 mmol) was added portion-wise. After about 15 min, MeI (2.41 mL, 38.5 mmol) was added and the mixture was stirred for about 15 min. The solvents were evaporated under reduced pressure and the residue was stirred with water (300 mL) for about 15 min at P. The slurry was treated with DCM (100 mL) and the layers were separated. The aqueous layer was extracted with DCM (30 mL) and the combined organics were washed with water (100 mL), dried over anhydrous MgSO4, filtered and concentrated in vacuo to give 3-iodo-5-methoxy-1-methyl-1H-indole (9.90 g, 99%) as a crude intermediate that was carried on to the next step without characterization.

Provenance & Evidence