Sodium hydride → 5-Bromo-1-(triisopropylsilyl)-1H-indole

Participants

Reaction Steps

5-Bromoindole (14.04 g, 72 mmol) in tetrahydrofuran (50 ml) was added dropwise to a suspension of sodium hydride (60% dispersion in oil; 3.04 g, 76 mmol) in tetrahydrofuran (100 ml) and the resultant solution stirred for one hour at room temperature. Triisopropylsilyltrifluoromethane sulphonate (23.3 g, 76 mmol) was added slowly and the solution stirred for a further one hour. The reaction mixture was washed with sodium hydrogen carbonate solution, dried (MgSO4), and concentrated. The crude mixture was purified by flash chromatography, with hexane as eluant, to give 5-bromo-1-triisopropylsilyl-1H-indole (20.0 g, 79%) as a clear oil; δH (CDCl3) 1.10 (18H, d, J 8.4 Hz, 6× CH3), 2.70 (3H, m, 3×CH), 6.55 (1H, d, J 3.9 Hz, ArH), 7.20 (2H, m, ArH), 7.35 (1H, d, J 8.5 Hz, ArH), and 7.75 (1H, d, J 1.4 Hz, ArH).

Provenance & Evidence