反应详情

2.77 Grams of [4-(3,4-dimethoxybenzoyl)-1-piperazinyl]-acetic acid was dissolved in 30 ml of DMF, then to this solution was added 1.2 g of triethylamine. Under ice-cooled condition with stirring, 1.4 g of isobutyl chloroformate was added dropwise thereto and stirred for 30 minutes. Further, the reaction mixture was stirred at a room temperature, a DMF solution of 1.46 g of o-carbamoylaniline was added dropwise to the mixture and was stirred for 6 hours. The reaction mixture obtained was concentrated to dryness, the residue was extracted with chloroform and 1N-sodium hydroxide aqueous solution. The chloroform layer was washed with water, dried then chloroform was removed by distillation. The residue obtained was purified by a silica gel column chromatography and the product obtained was converted into a hydrochloride by adding hydrochloric acid-ethanol, then recrystallized from water-acetone to obtain 0.7 g of o-carbamoyl-α-[4-(3,4-dimethoxybenzoyl)-1-piperazinyl]acetanilide monohydrochloride monohydrate in the form of colorless needle-like crystals. Melting point: 122.0°-125.0° C. (decomposed).

1. temperatureUnder ice-cooled condition
2. stirringstirred for 30 minutes
3. stirringFurther, the reaction mixture was stirred at a room temperature
4. stirringwas stirred for 6 hours
5. customThe reaction mixture obtained
6. concentrationwas concentrated to dryness
7. extractionthe residue was extracted with chloroform and 1N-sodium hydroxide aqueous solution
8. washThe chloroform layer was washed with water
9. customdried
10. customchloroform was removed by distillation
11. customThe residue obtained
12. customwas purified by a silica gel column chromatography
13. customthe product obtained
14. customrecrystallized from water-acetone