反应详情

To a solution of methyl 2-[(2,6-dichlorophenyl)amino]-6-hydroxy-7-nitro-1H-benzimidazole-5-carboxylate (Step-3 of Intermediate-55, 0.500 g) in benzene (2.0 mL) were added iron powder (0.500 g) and acetic acid (2.0 mL). The reaction mass was refluxed for 3 h. Decant the reaction mass removed the solvent under vacuum. The obtained solid mass was washed with water. The reaction mass was extracted with MeOH:DCM (5%). The organic layer was dried over anhydrous sodium sulphate and concentrated to afford 0.440 g of the desired product. 1HNMR (DMSO-d6): δ 3.87 (s, 3H), 4.45 (s, 2H), 7.28-7.47 (m, 1H), 7.53-7.59 (m, 3H), 11.00 (s, 2H).

1. temperatureThe reaction mass was refluxed for 3 h
2. customDecant the reaction mass
3. customremoved the solvent under vacuum
4. washThe obtained solid mass was washed with water
5. extractionThe reaction mass was extracted with MeOH
6. dry with materialThe organic layer was dried over anhydrous sodium sulphate
7. concentrationconcentrated