Hydrochloric Acid → 2-Amino-5-chloropyridin-3-ol

HRID 258564Notes

Reaction equation

HRID 258564 reaction equation
[OH-:1].[K+].[NH2:3][C:4]1[C:9](Br)=[CH:8][C:7]([Cl:11])=[CH:6][N:5]=1.Cl>[Cu].O>[NH2:3][C:4]1[C:9]([OH:1])=[CH:8][C:7]([Cl:11])=[CH:6][N:5]=1

Participants

6

Reactant 3

HCID 313Hydrochloric AcidHCID 14797Potassium HydroxideHCID 27639713-Bromo-5-chloropyridin-2-amine

Product 1

HCID 103132002-Amino-5-chloropyridin-3-olYield 70%

Reagents, catalysts & solvents 2

HCID 23978CopperCatalystHCID 962WaterSolvent

Conditions

Temperature
170 °C

Procedure

A mixture of 12 parts of potassium hydroxide (85%), 200 parts of water, 10.4 parts of 2-amino-3-bromo-5-chloropyridine and 0.5 part of copper powder is stirred under nitrogen in an autoclave for 10 hours at 170° C. The aqueous solution is afterwards neutralised with concentrated hydrochloric acid and the water is largely evaporated off. While still moist the residue is extracted in the hot state twice with ethyl acetate. The combined extracts are purified with active charcoal, and the solvent is then evaporated off to leave 5 parts (70% of theory) of 2-amino-3-hydroxy-5-chloropyridine, m.p. 196°-201° C.

Workup

  1. customthe water is largely evaporated off
  2. extractionWhile still moist the residue is extracted in the hot state twice with ethyl acetate
  3. customThe combined extracts are purified with active charcoal
  4. customthe solvent is then evaporated off

Sources & evidence

ORD record
ord-842e2554ff6647cd8bdc6689c98c502f
Source dataset
uspto-grants-1977_07
Patent number
US04033975

Reaction notes

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