N-Methylcarbazole → 3-bromo-9-methyl-9H-carbazole

Participants

Reaction Steps

To a solution of 1b (2.5 g, 13.8 mmol) in dichloromethane (80 mL) was added NBS (2.4 g, 13.8 mmol) portion-wise in an ice-water bath. After complete addition, the solution mixture was warmed to room temperature and stirred overnight. The resulting solution was washed with water and brine. The organic phase was dried over anhydrous sodium sulfate and the solvent was removed. The residue was purified by silica gel chromatography using ethyl acetate and petroleum ether (EA:PE=1:10) as eluent to afford 2b (2.11 g) in 59% yield. 1H NMR (400 MHz, CDCl3) δ 8.19 (d, J=2.0 Hz, 1H), 8.03 (d, J=8.0 Hz, 1H), 7.54 (dd, J=8.8 Hz, J=2.0 Hz, 1H), 7.50 (td, J=8.0 Hz, J=1.2 Hz, 1H), 7.39 (d, J=8.0 Hz, 1H), 7.27-7.22 (m, 2H), 3.82 (s, 3H).

Provenance & Evidence