Iodoethane → HCID 12816987, compound

HRID 223151Notes

Reaction equation

HRID 223151 reaction equation
[CH2:1]([O:3][C:4]([N:6]1[CH2:11][CH2:10][N:9]([C:12]2[N:21]=[C:20]3[C:15]([C:16](=[O:27])[C:17]([C:22]([O:24][CH2:25][CH3:26])=[O:23])=[CH:18][NH:19]3)=[CH:14][C:13]=2[F:28])[CH2:8][CH2:7]1)=[O:5])[CH3:2].C(=O)([O-])[O-].[K+].[K+].[CH2:35](I)[CH3:36]>CN(C)C=O>[CH2:35]([N:19]1[C:20]2[C:15](=[CH:14][C:13]([F:28])=[C:12]([N:9]3[CH2:10][CH2:11][N:6]([C:4]([O:3][CH2:1][CH3:2])=[O:5])[CH2:7][CH2:8]3)[N:21]=2)[C:16](=[O:27])[C:17]([C:22]([O:24][CH2:25][CH3:26])=[O:23])=[CH:18]1)[CH3:36]

Participants

5

Reactant 3

HCID 6340IodoethaneHCID 11430Potassium CarbonateHCID 12919356HCID 12919356, compound

Product 1

HCID 12816987HCID 12816987, compound

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

Ethyl 7-(4-ethoxycarbonyl-1-piperazinyl)-6-fluoro-1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylate was suspended in dimethylformamide (10 ml) and to the suspension was added potassium carbonate (0.53 g). After the mixture was kept at 60° C. for 10 minutes with stirring, ethyl iodide (1.2 g) was added to the solution. The mixture was stirred for 2 hours at 60°-70° C. The reaction mixture was concentrated to dryness under reduced pressure, and water was added to the residue. After extraction with chloroform, the chloroform extract was dried over anhydrous potassium carbonate. After removal of the chloroform by distillation, the resulting precipitate was recrystallized from a mixture of dichloromethane and n-hexane to give 0.89 g of ethyl 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(4-ethoxycarbonyl-1-piperazinyl)-1,8-naphthyridine-3-carboxylate (mp 171°-173° C.). A mixture of the above ethyl ester (0.8 g), 10% sodium hydroxide (6 ml) and ethanol (2 ml) was refluxed by heating for 3 hours. After cooling, the solution was adjusted to pH 7.0-7.5 with 10% acetic acid. The precipitate was collected by filtration, washed with ethanol and recrystallized from a mixture of dimethylformamide and ethanol to give 0.57 g of 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-1,8-naphthyridine-3-carboxylic acid. m.p. 220°-224° C.

Workup

  1. stirringThe mixture was stirred for 2 hours at 60°-70° C
  2. concentrationThe reaction mixture was concentrated to dryness under reduced pressure, and water
  3. additionwas added to the residue
  4. extractionAfter extraction with chloroform
  5. extractionthe chloroform extract
  6. dry with materialwas dried over anhydrous potassium carbonate
  7. customAfter removal of the chloroform
  8. distillationby distillation
  9. customthe resulting precipitate was recrystallized from a mixture of dichloromethane and n-hexane

Sources & evidence

ORD record
ord-f72cfee2d8ce4f5f9a90adfeec957faa
Source dataset
uspto-grants-1982_10
Patent number
US04352803

Reaction notes

Loading…