反应详情

To a mixture of 1-allyl-7-(1-ethylpropyl)-1,3-dihydro-2H-benzimidazol-2-one (22.0 g, 89.8 mmol) and zirconium chloride (1.05 g, 4.49 mmol) in toluene (300 mL) was added N-chlorosuccinimide (12.4 g, 92.5 g) portionwise at 0° C. After stirring for 15 hr, the mixture was concentrated in vacuo to give a residue which was partitioned in aqueous sodium bicarbonate and ethyl acetate. The aqueous layer was extracted with ethyl acetate. Combined organic layer was washed with aqueous sodium bicarbonate and brine, dried over anhydrous sodium sulfate and concentrated in vacuo. The residue was dissolved in hot ethyl acetate. n-Hexane was then added and the solution was cooled down. Resulting precipitate was collected by filtration to afford the title compound (9.60 g, 34.4 mmol, 38%) as a colorless solid.

1. concentrationthe mixture was concentrated in vacuo
2. customto give a residue which
3. customwas partitioned in aqueous sodium bicarbonate
4. extractionThe aqueous layer was extracted with ethyl acetate
5. washCombined organic layer was washed with aqueous sodium bicarbonate and brine
6. dry with materialdried over anhydrous sodium sulfate
7. concentrationconcentrated in vacuo
8. dissolutionThe residue was dissolved in hot ethyl acetate
9. additionn-Hexane was then added
10. temperaturethe solution was cooled down
11. customResulting precipitate
12. filtrationwas collected by filtration