反应详情

温度

70 °C

To a solution of 4-bromo-2-methyl-1-(2-methyl-3-(trifluoromethyl)benzyl)-6-nitro-1H-benzo[d]imidazole (55 g, 129 mmol) in methanol (600 mL) was added conc. HCl (20 mL), SnCl2 (174 g, 771 mmol) and the mixture was stirred at 70° C. for 2 h. Then the solvent was removed in vacuo, and the residue was diluted with 1N Na2CO3 solution (1.5 L) and extracted with DCM (200 mL×5). The combined organic layers were washed with brine, dried over sodium sulphate and evaporated to give the crude product (45 g, 88%) as a white solid; LC/MS: MS (ES+) m/e 398 [M+H]+; 1H NMR (300 MHz, DMSO-d6) δ ppm 2.37 (s, 3H), 2.52 (s, 3H), 5.06 (s, 2H), 5.40 (s, 2H), 6.35 (d, J=1.8 Hz, 1H), 6.37 (d, J=7.8 Hz, 1H), 6.74 (d, J=1.8 Hz, 1H), 7.26 (t, J=7.8 Hz, 1H), 7.60 (d, J=7.8 Hz, 1H).

1. customThen the solvent was removed in vacuo
2. additionthe residue was diluted with 1N Na2CO3 solution (1.5 L)
3. extractionextracted with DCM (200 mL×5)
4. washThe combined organic layers were washed with brine
5. dry with materialdried over sodium sulphate
6. customevaporated