反应详情

Ethyl 4-aminobenzoate (0.92 g) and triethylamine (1.5 mL) were dissolved in dichloromethane (10 mL), 3-chloropropane-1-sulfonyl chloride (0.9 mL) was added under ice-cooling, and the mixture was stirred at room temperature overnight. After completion of the reaction, 1N hydrochloric acid was added, and the mixture was extracted with chloroform. The organic layer was washed with saturated brine, and the solvent was evaporated. The obtained residue was dissolved in N,N-dimethylformamide (8 mL), 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) (1 mL) was added, and the mixture was stirred at room temperature for 3 hr. To the reaction mixture was added 1N hydrochloric acid, and the mixture was extracted with ethyl acetate. The organic layer was washed with saturated brine, and the solvent was evaporated. The obtained residue (1.5 g) was dissolved in ethanol (20 mL), 1N aqueous sodium hydroxide solution (8.4 mL) was added, and the mixture was stirred at 60° C. for 3 hr. To the reaction mixture were added 1N hydrochloric acid (9.2 mL) and water, and the precipitate was collected by filtration to give the title compound (0.98 g).

1. temperaturecooling
2. additionwas added
3. extractionthe mixture was extracted with chloroform
4. washThe organic layer was washed with saturated brine
5. customthe solvent was evaporated
6. dissolutionThe obtained residue was dissolved in N,N-dimethylformamide (8 mL)
7. addition1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) (1 mL) was added
8. stirringthe mixture was stirred at room temperature for 3 hr
9. additionTo the reaction mixture was added 1N hydrochloric acid
10. extractionthe mixture was extracted with ethyl acetate
11. washThe organic layer was washed with saturated brine
12. customthe solvent was evaporated
13. dissolutionThe obtained residue (1.5 g) was dissolved in ethanol (20 mL)
14. addition1N aqueous sodium hydroxide solution (8.4 mL) was added
15. stirringthe mixture was stirred at 60° C. for 3 hr
16. additionTo the reaction mixture were added 1N hydrochloric acid (9.2 mL) and water
17. filtrationthe precipitate was collected by filtration