反应详情

A mixture of 3.60 g of ethyl 3-nitro-4-phenylacetylaminobenzoate, 47 ml of ethanol, 23 ml of acetic acid and 6.4 g of reduced iron was heat-refluxed for 4 hours. The solid material was separated through filtration, and the filtrate was concentrated. To the residue were added 50 ml of ethanol and 5 g of 35% hydrochloric acid. The mixture was stirred for 40 hours while being heat-refluxed. The reaction solution was neutralized with sodium hydrogencarbonate, and was extracted with chloroform. The organic layer was concentrated under reduced pressure, and was purified through silica-gel column chromatography to give 2.30 g of 2-benzyl-5-ethoxycarbonylbenzimidazole (150).

1. temperaturewas heat-refluxed for 4 hours
2. customThe solid material was separated through filtration
3. concentrationthe filtrate was concentrated
4. additionTo the residue were added 50 ml of ethanol and 5 g of 35% hydrochloric acid
5. temperaturewhile being heat-refluxed
6. extractionwas extracted with chloroform
7. concentrationThe organic layer was concentrated under reduced pressure
8. customwas purified through silica-gel column chromatography