反应详情

To a solution of 2-chlorobenzooxazole-5-carbonitrile (1.69 g, 9.5 mmol) in EtOH (34 mL) was added Et3N (4.8 g, 47.5 mmol), followed by 1-cyclopropylpiperazine (1.44 g, 11.4 mmol) and the mixture was heated at reflux for 12 h. Then the volatiles were evaporated to remove EtOH and water (120 mL) was added. The mixture was extracted with CH2Cl2 (3×50 mL). The combined organic extracts were washed with brine, dried (Na2SO4) and concentrated. The residue was purified by column chromatography on silica gel (elute: 10% ethyl acetate in petroleum ether, 0.1% NH4OH added) to give 1.34 g (53%) of 2-(4-cyclopropylpiperazin-1-yl)benzooxazole-5-carbonitrile.

1. temperaturethe mixture was heated
2. temperatureat reflux for 12 h
3. customThen the volatiles were evaporated
4. customto remove EtOH and water (120 mL)
5. additionwas added
6. extractionThe mixture was extracted with CH2Cl2 (3×50 mL)
7. washThe combined organic extracts were washed with brine
8. dry with materialdried (Na2SO4)
9. concentrationconcentrated
10. customThe residue was purified by column chromatography on silica gel (elute: 10% ethyl acetate in petroleum ether, 0.1% NH4OH added)