Hydrochloric Acid → 7-(1-Piperazinyl)-1-cyclopropyl-6-fluoro-8-methyl-1,4-dihydro-4-oxoquinoline-3-carboxylic acid

HRID 2351917Notes

Reaction equation

HRID 2351917 reaction equation
[CH:1]1([N:4]2[C:13]3[C:8](=[CH:9][C:10]([F:26])=[C:11]([N:15]4[CH2:20][CH2:19][N:18](C(OCC)=O)[CH2:17][CH2:16]4)[C:12]=3[CH3:14])[C:7](=[O:27])[C:6]([C:28]([O:30]CC)=[O:29])=[CH:5]2)[CH2:3][CH2:2]1.[OH-].[Na+].Cl>>[N:15]1([C:11]2[C:12]([CH3:14])=[C:13]3[C:8]([C:7](=[O:27])[C:6]([C:28]([OH:30])=[O:29])=[CH:5][N:4]3[CH:1]3[CH2:2][CH2:3]3)=[CH:9][C:10]=2[F:26])[CH2:20][CH2:19][NH:18][CH2:17][CH2:16]1

Participants

4

Reactant 3

HCID 313Hydrochloric AcidHCID 14798Sodium HydroxideHCID 15631833Ethyl 1-cyclopropyl-7-(4-ethoxycarbonyl-1-piperazinyl)-6-fluoro-8-methyl-1,4-dihydro-4-oxoquinoline-3-carboxylate

Product 1

HCID 140525807-(1-Piperazinyl)-1-cyclopropyl-6-fluoro-8-methyl-1,4-dihydro-4-oxoquinoline-3-carboxylic acidYield 48.4%

Procedure

To ethyl 1-cyclopropyl-7-(4-ethoxycarbonyl-1-piperazinyl)-6-fluoro-8-methyl-1,4-dihydro-4-oxoquinoline-3-carboxylate (0.8 g) is added 10% aqueous sodium hydroxide (7 ml), and the mixture is refluxed for 5 hours. After cooling, the mixture is acidified with diluted hydrochloric acid and is extracted with dichloromethane. The aqueous layer is adjusted to about pH 7.5 with sodium hydrogen carbonate, and the resulting precipitates are separated by filtration to give 7-(1-piperazinyl)-1-cyclopropyl-6-fluoro-8-methyl-1,4-dihydro-4-oxoquinoline-3-carboxylic acid (0.3 g), m.p. 291°-295° C. (decomp.).

Workup

  1. temperaturethe mixture is refluxed for 5 hours
  2. temperatureAfter cooling
  3. extractionis extracted with dichloromethane
  4. customthe resulting precipitates
  5. customare separated by filtration

Sources & evidence

ORD record
ord-724f05294f004295a9cb3c02682465f9
Source dataset
uspto-grants-1989_10
Patent number
US04874764

Reaction notes

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