反应详情

温度

80 °C

To a solution of 2,3-dimethyl-6-nitro-2H-indazole (3.00 g, 15.69 mmol) in CCl4 (500 mL) was added AIBN (0.51 g, 3.14 mmol) and NBS (3.06 g, 17.26 mmol). The mixture was heated to 80° C. for 5 hours then stirred at rt overnight. Approximately half of the solvent was removed in vacuo, and the mixture was filtered. The filtrate was conc. in vacuo, and the crude product was purified by silica gel column chromatography eluting with ethyl acetate and hexane to afford 3-(bromomethyl)-2-methyl-6-nitro-2H-indazole with some succinimide present (4.41 g, 104% TY). 1H NMR (300 MHz, CDCl3) δ 8.68 (d, J=2.1 HZ, 1H), 7.98 (dd, J=9.3, 2.1 Hz, 1H), 7.74 (d, J=9.3 Hz, 1H), 4.87 (s, 2H), 4.28 (s, 3H). MS (ES+, m/z) 270, 272 (M+H).

1. customApproximately half of the solvent was removed in vacuo
2. filtrationthe mixture was filtered
3. customthe crude product was purified by silica gel column chromatography
4. washeluting with ethyl acetate and hexane