反应详情

A mixture of 8.03 g of methyl 2-acetylamino-3-nitrobenzoate, 18.8 g of reduced iron, 20 ml of acetic acid and 40 ml of ethanol was heat-refluxed for 18 hours. After the solvent was concentrated, chloroform and 10% hydrochloric acid were added to the residue for extraction. The aqueous layer was acidified with a saturated aqueous solution of sodium hydrogencarbonate, and was extracted with chloroform. Chloroform was then distilled off under reduced pressure to give 1.61 g of 4-ethoxycarbonyl-2-methylbenzimidazole (296).

1. temperaturewas heat-refluxed for 18 hours
2. concentrationAfter the solvent was concentrated
3. additionchloroform and 10% hydrochloric acid were added to the residue for extraction
4. extractionwas extracted with chloroform
5. distillationChloroform was then distilled off under reduced pressure