Hydrazine hydrate (1:1) → 8-Amino-5-fluoro-7-phenylpyrido[3,4-d]pyridazine-1,4(2H,3H)dione

HRID 37494Notes

Reaction equation

HRID 37494 reaction equation
[NH2:1][C:2]1[C:3]([C:19]2[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=2)=[N:4][C:5]([F:18])=[C:6]([C:13](OCC)=[O:14])[C:7]=1[C:8](OCC)=[O:9].O.[NH2:26][NH2:27]>C(O)C>[NH2:1][C:2]1[C:7]2[C:8](=[O:9])[NH:27][NH:26][C:13](=[O:14])[C:6]=2[C:5]([F:18])=[N:4][C:3]=1[C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1

Participants

4

Reactant 2

HCID 24654Hydrazine hydrate (1:1)HCID 152896983-Amino-6-fluoro-4,5-diethoxycarbonyl-2-phenylpyridine

Product 1

HCID 152896778-Amino-5-fluoro-7-phenylpyrido[3,4-d]pyridazine-1,4(2H,3H)dione

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

In 1 ml of ethanol was dissolved 90 mg of 3-amino-6-fluoro-4,5-diethoxycarbonyl-2-phenylpyridine, followed by addition of 2 ml of hydrazine monohydrate. The mixture was stirred at room temperature for 4 hours. After the solvent was distilled off, the resulting crystals were collected by filtration with ethanol. Water was added to the crystals, and the mixture was neutralized with 1N hydrochloric acid, followed by collection by filtration. A methanol solution of the crystals was mixed with silica gel and purified by silica gel column chromatography (eluent:ethyl acetate→ethyl acetate/methanol 1:1), followed by collection by filtration with water.

Workup

  1. distillationAfter the solvent was distilled off
  2. filtrationthe resulting crystals were collected by filtration with ethanol
  3. additionWater was added to the crystals
  4. filtrationfollowed by collection by filtration
  5. additionA methanol solution of the crystals was mixed with silica gel
  6. custompurified by silica gel column chromatography (eluent:ethyl acetate→ethyl acetate/methanol 1:1)
  7. filtrationfollowed by collection by filtration with water

Sources & evidence

ORD record
ord-4dc5d459cc454e6ba582b5719c309090
Source dataset
uspto-grants-1995_05
Patent number
US05420275

Reaction notes

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