Dimethylformamide → 5-Bromo-1-methyl-1H-indole

Participants

Reaction Steps

To a solution of 5-bromoindole (1.0 g, 5.10 mmol) in DMC (10 mL), DABCO (0.057 g, 0.51 mmol) is added followed by DMF (1 mL). The resulting solution is heated to 90–95° C. for 5 h. The reaction is cooled to RT, and diluted with ethyl acetate (EtOAc, 50 mL) and H2O (50 mL). The organic layer is separated and washed in sequence with H2O (50 mL), 10% aqueous citric acid (2×50 mL) and H2O (4×50 mL). The organic layer is dried over anhydrous sodium sulfate (Na2SO4), filtered and concentrated under vacuum to give 5-bromo-1-methylindole (about 1.06 g, 99%) as a golden colored solid: 1H NMR (CDCl3) δ 7.72 (d, 1H), 7.26 (dd, 1H), 7.13 (d, 1H), 7.00 (d, 1H), 6.39 (d, 1H), 3.71 (s, 3H); 13C NMR (CDCl3) δ 135.3, 130.1, 129.9, 124.2, 123.2, 112.6, 110.6, 100.5, 32.9; MS m/z 209 [M+1]+.

Provenance & Evidence