1,3-Dibromopropane → Indole-bromide

Participants

Reaction Steps

2-Methyl-3-benzyloxycarbonyl-5-hydroxyindole (0.558 g, 1.980 mmol, 1 eq) was suspended in acetonitrile (10 mL) under Ar. Cs2CO3 (0.645 g, 1.980 mmol, 1 eq) and KI (0.328 g, 1.980 mmol, 1 eq) were added followed by 1,3-dibromopropane (0.523 g, 2.590 mmol, 1.3 eq). The reaction mixture was stirred and heated to reflux for 20 hours. Then the reaction was quenched with saturated sodium bicarbonate and extracted with ethyl acetate (3×). The combined organic phases were washed with brine and dried over Na2SO4. After removing the solvent, the residue was loaded on silica gel and chromatographed, eluting with ethyl acetate/hexane (1/5). 0.244 g (31%) of the indole-bromide was obtained as a colorless oil.

Provenance & Evidence