2-Chloropyridine → Picolinic acid

HRID 1266628Notes

Reaction equation

[C:1](=[O:4])([O-])[O-:2].[Na+].[Na+].Cl[C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][N:9]=1.C12(PC34CC(CC3)CC4)CC(CC1)CC2>C(O)C.O.C(Cl)Cl.[Cl-].[Cl-].C(#N)C1C=CC=CC=1.C(#N)C1C=CC=CC=1.[Pd+2]>[N:9]1[CH:10]=[CH:11][CH:12]=[CH:13][C:8]=1[C:1]([OH:2])=[O:4]

Participants

Conditions

Temperature: 100 °C

Procedure

Sodium carbonate (3.34 g, 32 mmols), 2-chloropyridine (2.38 g, 21 mmols) and 40 ml of ethanol are placed in a glass autoclave. The autoclave is rinsed with nitrogen and heated to 100° C. A solution of palladium bis(benzonitrile) dichloride (161 mg, 0.42 mmols) and dinorbornylphosphine (420 mg, 1.90 mmols) in 2 ml of ethanol (prepared under argon) is added, and then 5 bars CO are applied. After 16 hours at 120° C., the mixture is allowed to cool. The reaction mixture is taken up in water and methylene chloride. The aqueous phase is separated, acidified with concentrated hydrochloric acid and concentrated. The residue is extracted with ethanol and, after filtration, the ethanol is distilled off in a vacuum. The solid is recrystallised from water/ethanol/acetone. Yield of title compound as the hydrochloride: 2.13 g (64%).

Workup

washThe autoclave is rinsed with nitrogen
temperatureto cool
customThe aqueous phase is separated
concentrationconcentrated
extractionThe residue is extracted with ethanol
filtrationafter filtration
distillationthe ethanol is distilled off in a vacuum
customThe solid is recrystallised from water/ethanol/acetone

Sources & evidence

ORD record: ord-796e4c62a0e44f13b50f791c0de1c113
Source dataset: uspto-grants-2003_04
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US06548684B2

Reaction notes

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