Hydrochloric Acid → 5-Methyl-4-pyridazinecarboxylic acid

HRID 1685040Notes

Reaction equation

HRID 1685040 reaction equation
[CH3:1][C:2]1[C:3]([C:8]([O:10]CC)=[O:9])=[CH:4][N:5]=[N:6][CH:7]=1.[OH-].[Na+].Cl>O.C1COCC1>[CH3:1][C:2]1[C:3]([C:8]([OH:10])=[O:9])=[CH:4][N:5]=[N:6][CH:7]=1

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 14798Sodium HydroxideHCID 13262526Ethyl 5-methylpyridazine-4-carboxylate

Product 1

HCID 574169155-Methyl-4-pyridazinecarboxylic acidYield 185.1%

Reagents, catalysts & solvents 1

HCID 21881883Oxolane--water (1/1)Solvent

Conditions

Temperature
60 °C

Procedure

To a solution of ethyl 5-methylpyridazine-4-carboxylate (240 mg, 1.4 mmol) in H2O/THF was added 7.5 N aq. NaOH (1.25 eq, 0.25 mL) and the mixture was stirred for 1 hour at 60° C. Concentrated HCl was added to pH 2 and subsequently the volatiles were removed in vacuo. The residue was first stirred with EtOAc and the solids were collected by filtration. Then stirred with THF and the solids were again collected by filtration. The solids were extracted with MeOH and removal of the volatiles afforded 5-methylpyridazine-4-carboxylic acid (358 mg) as a brown solid.

Workup

  1. customsubsequently the volatiles were removed in vacuo
  2. stirringThe residue was first stirred with EtOAc
  3. filtrationthe solids were collected by filtration
  4. stirringThen stirred with THF
  5. filtrationthe solids were again collected by filtration
  6. extractionThe solids were extracted with MeOH and removal of the volatiles

Sources & evidence

ORD record
ord-703e97f0e652443db16f0acbebce704f
Source dataset
uspto-grants-2012_04
Patent number
US08148380B2

Reaction notes

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