Sodium hydride → 6-bromo-1-(triisopropylsilyl)-1H-indole

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of 6-bromo-1H-indole (2.04 g, 1.04 mmol) in THF under nitrogen at 0° C. was added sodium hydride (60%, 1.25 g 31.2 mmol), portionwise over 0.2 h. The mixture was stirred at 0-20° C. for 1 h then was cooled in an ice-MeOH bath, whereupon triisopropylsilyl trifluoromethylsulfonate (3.83 g, 12.5 mmol) was added dropwise over 3 h. The resulting mixture was stirred at 0° C. for 1 h then at 20° C. for 72 h. The mixture was quenched (caution,) with a mixture of THF (30 mL) and water (1 mL) with external ice cooling and the resulting clear solution was partitioned between water (100 mL) and DCM (3×50 mL). The combined organic extracts were dried (Na2SO4) and evaporated in vacuo to give an oil. Chromatography (SiO2; gradient elution with 0-40% Et2O in petrol) gave the title compound (3.48 g) as a colourless oil. 1H NMR (CDCl3): 7.66-7.64 (1H, m), 7.50 (1H, d), 7.25-7.21 (2H, m), 6.61 (1H, d), 1.76-1.64 (3H, m), 1.17 (18H, d).

Provenance & Evidence