Methyl iodide → 4-Chloro-1-methyl-1H-indole

Participants

Reaction Steps

In an oven dried, nitrogen purged, 3 neck, 50 mL round bottom flask, 0.794 mL (6.60 mmol) of 4-chloroindole in 10 mL of dry dimethylformamide is reacted with 0.260 g (6.60 mmol) of 60% sodium hydride dispersed in mineral oil at room temperature for 4 h. 0.411 mL (6.60 mmol) of iodomethane is added and the reaction is allowed to stir at room temperature 15 h. TLC (2:1 hexanes:ethyl acetate) indicates the starting material is gone and new less polar spot. The reaction is quenched with 50 mL of water, extracted 3×50 mL of ethyl acetate, dried (MgSO4), and concentrated. The crude product is purified by chromatography using hexanes:ethyl acetate as a solvent system to obtain 0.785 g of the title compound, 72% yield. MS, ES=166.1 (M+1); 1H NMR (DMSO-d6) δ 7.431-7.413 (m, 2H); 7.145-7.064 (m, 2H); 6.442-6.432 (m, 1H); 3.795 (s, 3H) ppm.

Provenance & Evidence