反应详情

To a suspension of 23.6 grams of benzimidazole in 300 ml of dioxane was added 9.8 grams of a 50% dispersion of sodium hydride in mineral oil and the resulting mixture was stirred at room temperature for two hours. A solution of 20.7 grams of 4-chlorobutyronitrile in 100 ml of dioxane was added and the mixture was refluxed for 5 hours. Then, an additional 3 grams of sodium hydride suspension was added and the mixture was refluxed for 17 hours. The mixture was then filtered, concentrated, and washed with petroleum ether to remove the mineral oil. The residual brown oil was then chromatographed on silica gel packed with chloroform and eluted with chloroform and chloroform containing increasing quantities of methanol. The fractions eluted with 0.5% and 1% methanol were combined and the solvent was evaporated to leave residual crude 1H-benzimidazole-1-butanenitrile.

1. temperaturethe mixture was refluxed for 5 hours
2. temperaturethe mixture was refluxed for 17 hours
3. filtrationThe mixture was then filtered
4. concentrationconcentrated
5. washwashed with petroleum ether
6. customto remove the mineral oil
7. customThe residual brown oil was then chromatographed on silica gel
8. washeluted with chloroform and chloroform containing
9. temperatureincreasing quantities of methanol
10. washThe fractions eluted with 0.5% and 1% methanol
11. customthe solvent was evaporated