6-Amino-1-ethyl-1,4-dihydro-7-(2,6-dimethyl-4-pyridinyl)-4-oxo-3-quinolinecarboxylic acid monohydrate → 3-Carboxy-1-ethyl-1,4-dihydro-7-(2,6-dimethyl-4-pvridinyl)-4oxo-6-quinolinyldiazonium hexafluorophosphate

HRID 255574Notes

Reaction equation

HRID 255574 reaction equation
O.[NH2:2][C:3]1[CH:4]=[C:5]2[C:10](=[CH:11][C:12]=1[C:13]1[CH:18]=[C:17]([CH3:19])[N:16]=[C:15]([CH3:20])[CH:14]=1)[N:9]([CH2:21][CH3:22])[CH:8]=[C:7]([C:23]([OH:25])=[O:24])[C:6]2=[O:26].[N:27]([O-])=O.[Na+].[F:31][P-:32]([F:37])([F:36])([F:35])([F:34])[F:33].[H+]>Cl.O>[F:31][P-:32]([F:37])([F:36])([F:35])([F:34])[F:33].[C:23]([C:7]1[C:6](=[O:26])[C:5]2[C:10](=[CH:11][C:12]([C:13]3[CH:14]=[C:15]([CH3:20])[N:16]=[C:17]([CH3:19])[CH:18]=3)=[C:3]([N+:2]#[N:27])[CH:4]=2)[N:9]([CH2:21][CH3:22])[CH:8]=1)([OH:25])=[O:24]

Participants

6

Reactant 3

HCID 139585056-Amino-1-ethyl-1,4-dihydro-7-(2,6-dimethyl-4-pyridinyl)-4-oxo-3-quinolinecarboxylic acid monohydrateHCID 16211447Hexafluorophosphoric acidHCID 23668193Sodium Nitrite

Product 1

HCID 139585063-Carboxy-1-ethyl-1,4-dihydro-7-(2,6-dimethyl-4-pvridinyl)-4oxo-6-quinolinyldiazonium hexafluorophosphateYield 78%

Reagents, catalysts & solvents 2

HCID 313Hydrochloric AcidSolventHCID 962WaterSolvent

Procedure

A 20 g portion of 6-amino-1-ethyl-1,4-dihydro-7-(2,6-dimethyl-4-pyridinyl)-4-oxo-3-quinolinecarboxylic acid monohydrate was suspended in 100 ml of 6 N HCl and placed in an ice/salt bath. When the temperature of the mixture had reached -10° C., a cold solution of 4.5 g of NaNO2 in 20 ml of H2O was added in portions over a period of a few minutes. The reaction mixture was stirred for 5-10 minutes during which time it became a clear solution. Hexafluorophosphoric acid (18 ml) was carefully added in one portion whereupon a precipitate separated immediately, the temperature rising to 0° C. before dropping again. The reaction mixture was stirred for 30 minutes after addition; and, then the precipitate was collected and washed successively with water, a small volume of cold ethanol, and finally with ether. The product was vacuum-dried at 50° C. for 48 hours in the presence of P2O5 to give 29.7 g (78%) of 3-carboxy-1-ethyl-1,4-dihydro-7-(2,6-dimethyl-4-pvridinyl)-4oxo-6-quinolinyldiazonium hexafluorophosphate as its hydrohexafluorophosphate, m.p. 200°-205° C. with decomposition.

Workup

  1. customplaced in an ice/salt bath
  2. customhad reached -10° C.
  3. customseparated immediately
  4. customrising to 0° C.
  5. stirringThe reaction mixture was stirred for 30 minutes
  6. additionafter addition
  7. customand, then the precipitate was collected
  8. washwashed successively with water
  9. dry with materialThe product was vacuum-dried at 50° C. for 48 hours in the presence of P2O5

Sources & evidence

ORD record
ord-dd01c7d8a5a342888b84ccc8bff001c0
Source dataset
uspto-grants-1987_10
Patent number
US04698350

Reaction notes

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