反应详情

To a solution of 6-bromo-2-chlorobenzothiazole (8.2 g, 33 mmol) in EtOH (115 mL) was added Et3N (16.7 g, 165 mmol), followed by 1-cyclopropylpiperazine (5 g, 39.6 mmol). The mixture was heated at reflux for 12 h. Then the mixture was evaporated to remove EtOH. Water (120 mL) was added to the residue and the mixture was extracted with CH2Cl2 (3×50 mL). The combined organic extracts were washed with brine, dried (Na2SO4) and concentrated to give a residue, which was purified by column chromatography on silica gel eluting with a mixture of EtOAc/petroleum ether (1:10 with 0.1% NH4OH added) to give 3.46 g (31%) 6-bromo-2-(4-cyclopropylpiperazin-1-yl)benzothiazole.

1. temperatureThe mixture was heated
2. temperatureat reflux for 12 h
3. customThen the mixture was evaporated
4. customto remove EtOH
5. additionWater (120 mL) was added to the residue
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. customto give a residue, which
11. customwas purified by column chromatography on silica gel eluting with a mixture of EtOAc/petroleum ether (1:10 with 0.1% NH4OH added)