Sodium Hydroxide → 5-Chloro-3-nitropyridine-2-carboxylic acid

HRID 1438423Notes

Reaction equation

HRID 1438423 reaction equation
[Cl:1][C:2]1[CH:3]=[C:4]([N+:14]([O-:16])=[O:15])[C:5]([C:8]#CC(C)(O)C)=[N:6][CH:7]=1.[O-:17][Mn](=O)(=O)=O.[K+].[OH-:23].[Na+]>O>[Cl:1][C:2]1[CH:3]=[C:4]([N+:14]([O-:16])=[O:15])[C:5]([C:8]([OH:17])=[O:23])=[N:6][CH:7]=1

Participants

5

Conditions

Temperature
77.5 °C

Procedure

A suspension of the alkyne from step 1 (1.96 g, 8.2 mmol) in water (20 mL) was heated at 75-80 ° C. KMnO4 (4.27 g, 27.1 mmol) was added portion wise over 30 min. After complete addition, heating was continued for 45 min. The reaction mixture was then cooled to room temperature and the pH adjusted to 9 by the addition of 1.0 M aqueous NaOH and filtered through filter paper. The filter cake was thoroughly washed with 0.3 M aqueous NaOH. The filtrate was extracted with EtOAc and discarded. The aqueous part was acidified to pH 3-4 with 1 M HCl and saturated with solid NaCl. This solution was extracted with EtOAc (4×30 mL). The combined extract was dried (Na2SO4) and concentrated under reduced pressure to provide the crude acid (500 mg). MS m/z: 200.8 (M−H).

Workup

  1. additionAfter complete addition
  2. temperatureheating
  3. temperatureThe reaction mixture was then cooled to room temperature
  4. filtrationfiltered
  5. filtrationthrough filter paper
  6. washThe filter cake was thoroughly washed with 0.3 M aqueous NaOH
  7. extractionThe filtrate was extracted with EtOAc
  8. extractionThis solution was extracted with EtOAc (4×30 mL)
  9. extractionThe combined extract
  10. dry with materialwas dried (Na2SO4)
  11. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-355c03f1d2c94bcb9adcfd816f5557c6
Source dataset
uspto-grants-2009_11
Patent number
US07622583B2

Reaction notes

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