反应详情

A mixture of 2-chloro-1H-benzimidazole (6.10 g), bromoacetaldehyde diethyl acetal (7.22 mL), EtOH (70 mL), and 8 M NaOH aqueous solution (10 mL) was refluxed for 3 d. The reaction mixture was poured into water and the mixture was extracted with AcOEt. The extract was washed with brine, dried over MgSO4, and concentrated under reduced pressure. The residue was purified by basic silica gel column chromatography eluting with hexane/AcOEt (10/1) to give 2-chloro-1-(2,2-diethoxyethyl)-1H-benzimidazole (5.50 g).

1. temperaturewas refluxed for 3 d
2. extractionthe mixture was extracted with AcOEt
3. washThe extract was washed with brine
4. dry with materialdried over MgSO4
5. concentrationconcentrated under reduced pressure
6. customThe residue was purified by basic silica gel column chromatography
7. washeluting with hexane/AcOEt (10/1)