Piperazine → Ciprofloxacin

HRID 1284516Notes

Reaction equation

HRID 1284516 reaction equation
Cl[C:2]1[CH:11]=[C:10]2[C:5]([C:6](=[O:18])[C:7]([C:15]([OH:17])=[O:16])=[CH:8][N:9]2[CH:12]2[CH2:14][CH2:13]2)=[CH:4][C:3]=1[F:19].[NH:20]1[CH2:25][CH2:24][NH:23][CH2:22][CH2:21]1>CS(C)=O>[CH:12]1([N:9]2[C:10]3[C:5](=[CH:4][C:3]([F:19])=[C:2]([N:20]4[CH2:25][CH2:24][NH:23][CH2:22][CH2:21]4)[CH:11]=3)[C:6](=[O:18])[C:7]([C:15]([OH:17])=[O:16])=[CH:8]2)[CH2:14][CH2:13]1

Participants

4

Reactant 2

HCID 4837PiperazineHCID 483180Fluoroquinolonic acid

Product 1

HCID 2764CiprofloxacinYield 84.6%

Reagents, catalysts & solvents 1

HCID 679Dimethyl SulfoxideSolvent

Procedure

A mixture of 19.7 g of 7-chloro-1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-3-quinolinecarboxylic acid, 30.1 g of anhydrous piperazine and 100 ml of dimethylsulphoxide is heated at 135° to 140° C. for 2 hours. The solvent is distilled off under a fine vacuum and the residue is suspended in H2O, filtered off with suction and washed with water. For further purification, the moist crude product is boiled up with 100 ml of water, filtered off with suction at room temperature, washed with H2O and dried to constant weight at 100° C. over CaCl2 in a vacuum drying cabinet. 19.6 g of 1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinolinecarboxylic acid of decomposition point 255° to 257° C. are obtained;

Workup

  1. temperatureis heated at 135° to 140° C. for 2 hours
  2. distillationThe solvent is distilled off under a fine vacuum
  3. filtrationfiltered off with suction
  4. washwashed with water
  5. customFor further purification
  6. filtrationfiltered off with suction at room temperature
  7. washwashed with H2O
  8. dry with materialdried to constant weight at 100° C. over CaCl2 in a vacuum
  9. customdrying cabinet

Sources & evidence

ORD record
ord-578bf11210854b14a8074da8ad48a930
Source dataset
uspto-grants-1986_01
Patent number
US04563448

Reaction notes

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