Hydrochloric Acid → 4,6-Dichloro-3-pyridazinecarboxylic acid

HRID 1161812Notes

Reaction equation

HRID 1161812 reaction equation
[Cl:1][C:2]1[CH:7]=[C:6]([Cl:8])[N:5]=[N:4][C:3]=1[C:9]([O:11]C)=[O:10].[Li+].[OH-].Cl>C1COCC1.O>[Cl:1][C:2]1[CH:7]=[C:6]([Cl:8])[N:5]=[N:4][C:3]=1[C:9]([OH:11])=[O:10]

Participants

6

Reactant 3

HCID 313Hydrochloric AcidHCID 3939Lithium HydroxideHCID 17848322Methyl 4,6-dichloropyridazine-3-carboxylate

Product 1

HCID 219192804,6-Dichloro-3-pyridazinecarboxylic acid

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8028TetrahydrofuranSolvent

Procedure

To a solution of methyl 4,6-dichloro-pyridazine-3-carboxylate (6.01 g, 29.03 mmol, WO 2004/031174) in THF (29 ml) at 0° C. is added 29 ml of aqueous 1.0 M LiOH with stirring. The resulted mixture is stirred continuously at 0° C. for 40 min and monitored by TLC. The reaction mixture is diluted with water, and acidified to pH 1-2 with aqueous 1.0 M HCl. The crude product is suspended between the organic and aqueous layers. After filtration and washed with water and hexane, and dried under vacuum, the product is obtained.

Workup

  1. stirringThe resulted mixture is stirred continuously at 0° C. for 40 min
  2. filtrationAfter filtration
  3. washwashed with water and hexane
  4. customdried under vacuum
  5. customthe product is obtained

Sources & evidence

ORD record
ord-7bf27efdcffa45a881c60ff20960668e
Source dataset
uspto-grants-2010_10
Patent number
US07820664B2

Reaction notes

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