반응 #1388

반응 방정식

ethyl 7-(1-piperazinyl)-1-cyclopropyl-6-fluoro-5-methyl-1,4-dihydro-4-oxoquinoline-3-carboxylate

sodium hydroxide

ethanol

→

7-(1-piperazinyl)-1-cyclopropyl-6-fluoro-5-methyl-1,4-dihydro-4-oxoquinoline-3-carboxylic acid

수율 56.4%

용매

water

반응 조건

후처리

1. 1
   온도the mixture is refluxed for 1 hour
2. 2
   온도After cooling
3. 3
   세척washed with dichloromethane
4. 4
   추출The resultant is extracted with dichloromethane
5. 5
   기타the extract is dried
6. 6
   workup.DISTILLATIONThe solvent is distilled off under reduced pressure and to the residue
7. 7
   workup.ADDITIONis added ethanol
8. 8
   여과The precipitated crystals are filtered
9. 9
   기타recrystallized from dimethylformamide

실험 절차

To ethyl 7-(1-piperazinyl)-1-cyclopropyl-6-fluoro-5-methyl-1,4-dihydro-4-oxoquinoline-3-carboxylate (23 mg) are added 10% aqueous solution of sodium hydroxide (3 ml) and ethanol (3 ml), and the mixture is refluxed for 1 hour. After cooling, the reaction mixture is diluted with water and washed with dichloromethane. After the aqueous layer is made acidic with acetic acid and then made weak alkaline with an aqueous sodium hydrogen carbonate. The resultant is extracted with dichloromethane and the extract is dried. The solvent is distilled off under reduced pressure and to the residue is added ethanol. The precipitated crystals are filtered and recrystallized from dimethylformamide to give 7-(1-piperazinyl)-1-cyclopropyl-6-fluoro-5-methyl-1,4-dihydro-4-oxoquinoline-3-carboxylic acid (12 mg), as white powder, m.p. 231°-233° C.

출처