反应详情

温度

70 °C

To a solution of methyl 4-bromo-3-methylbenzoate (Aldrich 532878, 50 g; 218 mmol; 1 eq.) in CHCl3 (1 L) were added NBS (46.6 g; 262 mmol; 1.2 eq.) in one portion and α,α′-azoisobutyronitrile (0.72 g; 4.37 mmol; 0.02 eq.). The reaction mixture was stirred at 70° C. for 2 days. It was cooled down to RT and water (500 mL) was added. The organic layer was washed with aq. NaHCO3 (400 mL), then brine (500 mL), dried over MgSO4 and concentrated in vacuo. The residue was washed with n-pentane (2×500 mL) to afford the title compound as a yellow solid. 1H NMR (DMSO-d5, 300 MHz) δ 8.24 (d, J=1.9 Hz, 1H), 7.88-7.82 (m, 2H), 4.87 (s, 2H), 3.91 (s, 3H). HPLC (Method A): Rt 4.44 min (purity 97.9%).

1. temperatureIt was cooled down to RT
2. washThe organic layer was washed with aq. NaHCO3 (400 mL)
3. dry with materialbrine (500 mL), dried over MgSO4
4. concentrationconcentrated in vacuo
5. washThe residue was washed with n-pentane (2×500 mL)