Hydrochloric Acid → 1-(4-Fluorophenyl)-5-bromo-1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid

HRID 67256Notes

Reaction equation

HRID 67256 reaction equation
[F:1][C:2]1[CH:7]=[CH:6][C:5]([N:8]2[C:13]([CH3:14])=[CH:12][C:11](=[O:15])[C:10]([C:16]([OH:18])=[O:17])=[N:9]2)=[CH:4][CH:3]=1.[OH-].[Na+].[Br:21]Br.Cl>CO>[F:1][C:2]1[CH:7]=[CH:6][C:5]([N:8]2[C:13]([CH3:14])=[C:12]([Br:21])[C:11](=[O:15])[C:10]([C:16]([OH:18])=[O:17])=[N:9]2)=[CH:4][CH:3]=1

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 14798Sodium HydroxideHCID 24408BromineHCID 117157481-(4-Fluorophenyl)-1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid

Product 1

HCID 130841591-(4-Fluorophenyl)-5-bromo-1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acidYield 70.8%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent2×

Procedure

1-(4-Fluorophenyl)-1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid (1.5 g) is suspended in 100 ml of dry methanol, and 0.242 g of sodium hydroxide is added. To the solution is added dropwise 1.038 g of bromine dissolved in 50 ml of methanol. The solvent is removed leaving a white solid, which is taken up in dilute base and the solution acidified with hydrochloric acid. The resulting precipitate is filtered and recrystallized from chloroform/ether to yield 1.4 g of 1-(4-fluorophenyl)-5-bromo-1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid. (mp-219°-20°).

Workup

  1. customThe solvent is removed
  2. customleaving a white solid, which
  3. filtrationThe resulting precipitate is filtered
  4. customrecrystallized from chloroform/ether

Sources & evidence

ORD record
ord-0e905e23772049a989cb0228e33b09d4
Source dataset
uspto-grants-1982_08
Patent number
US04345934

Reaction notes

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