反应详情

In ethanol (21 ml) and concentrated hydrochloric acid (7 ml) was dissolved N-(2-amino-3,5-dibromophenyl)-N-ethoxycarbonyl-N',N'-dimethylethylenediamine (0.85 g) and the solution was refluxed for 2 hours. The reaction mixture was concentrated under reduced pressure and the residue was diluted with water. The solution was alkalized with sodium hydroxide and extracted with ethyl acetate. The organic layer was washed with saturated aqueous sodium chloride solution and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure and the residue was purified by silica gel chromatography (eluent: chloroform:methanol=10:1) to give 0.59 g of 4,6-dibromo-1,3-dihydro-1-(2-dimethylaminoethyl)-2H-benzimidazol-2-one.

1. temperaturethe solution was refluxed for 2 hours
2. concentrationThe reaction mixture was concentrated under reduced pressure
3. additionthe residue was diluted with water
4. extractionextracted with ethyl acetate
5. washThe organic layer was washed with saturated aqueous sodium chloride solution
6. dry with materialdried over anhydrous sodium sulfate
7. distillationThe solvent was distilled off under reduced pressure
8. customthe residue was purified by silica gel chromatography (eluent: chloroform:methanol=10:1)