反应详情

4-Amino-2-methylbenzimidazole (0.79 g, 5.4 mmol) and 2,6-diethylbenzaldehyde (1.1 g, 6.6 mmol) were dissolved in methanol (30 ml). ZnCl2 (0.9 g, 6.6 mmol) and subsequently NaBH3CN (0.42 g, 6.6 mmol) in small portions were added and the mixture was refluxed under argon for 3 hours and was stirred at room temperature for 16 h. The mixture was poured over an aqueous 1M NaOH solution (50 ml). The resultant yellow suspension was extracted with DCM and the organic solution was washed with brine, dried over Na2SO4 and then evaporated under reduced pressure. The oily residue (1.8 g) was purified by crystallization from a mixture of ethyl acetate and acetonitrile to give 0.65 g (41%) of the title compound.

1. temperaturethe mixture was refluxed under argon for 3 hours
2. extractionThe resultant yellow suspension was extracted with DCM
3. washthe organic solution was washed with brine
4. dry with materialdried over Na2SO4
5. customevaporated under reduced pressure
6. customThe oily residue (1.8 g) was purified by crystallization from a mixture of ethyl acetate and acetonitrile