Water → 7-(3-chloropropoxy)-1H-indole

To a stirred suspension of sodium hydride (0.8 g, 17 mmol of a 50% oil dispersion) in dimethylformamide (20 ml), under nitrogen, was added dropwise 7-hydroxyindole (2.1 g, 15.7 mmol) in dimethylformamide (20 ml). After complete addition, the reaction was stirred at ambient temperature for 0.5 hour and then cooled to 15° C. To this cooled solution was added, dropwise, 1-bromo-3-chloropropane (2.5 g, 15.7 mmol) in dimethylformamide (5 ml). The reaction was then stirred at ambient temperature for 16 hours. The reaction was poured into water, and the aqueous suspension extracted with ethyl acetate. The ethyl acetate was washed with water, dried (MgSO4), and the solvent was concentrated to afford a dark brown oil. Following flash chromatography on silica gel, 7-(3-chloropropoxy)indole was obtained as a colorless oil, 1.0 g.