反应详情

A suspension of 2-amino-3-methoxy-N-methylaniline (671 mg) and acetic acid (265 mg) in 4N hydrochloric acid (3.5 ml) was refluxed for 10 hours. Insoluble material was filtered off, and the filtrate was adjusted to pH 7 with saturated sodium bicarbonate solution, and extracted with dichloromethane. The organic layers were combined, washed with brine, dried over magnesium sulfate and evaporated in vacuo. The residue was purified by silica gel flash chromatography (dichloromethane:methanol=40:1, v/v) to give 1,2-dimethyl-4-methoxy-1H-benzimidazole (680 mg).

1. temperaturewas refluxed for 10 hours
2. filtrationInsoluble material was filtered off
3. extractionextracted with dichloromethane
4. washwashed with brine
5. dry with materialdried over magnesium sulfate
6. customevaporated in vacuo
7. customThe residue was purified by silica gel flash chromatography (dichloromethane