Hydrochloric Acid → 5-Bromo-3-fluoropyridine-2-carboxylic acid

HRID 1374167Notes

Reaction equation

HRID 1374167 reaction equation
[Br:1][C:2]1[CH:3]=[C:4]([F:11])[C:5]([C:8](N)=[O:9])=[N:6][CH:7]=1.Cl.[OH-:13].[Na+]>>[Br:1][C:2]1[CH:3]=[C:4]([F:11])[C:5]([C:8]([OH:13])=[O:9])=[N:6][CH:7]=1

Participants

4

Reactant 3

HCID 313Hydrochloric AcidHCID 14798Sodium HydroxideHCID 210758715-Bromo-3-fluoropyridine-2-carboxamide

Product 1

HCID 210758725-Bromo-3-fluoropyridine-2-carboxylic acid

Procedure

A solution of crude 5-bromo-3-fluoropyridine-2-carboxamide (40.50 g, 184.9 mmol) in HCl (12N, 539.4 mL, 6.472 mol) was heated to 120° C. for 1 hour. The reaction was cooled to room temperature, and NaOH (20%) was added slowly to pH˜6. The solution was concentrated in vacuo, and azeotroped 3×with toluene. The residue was extracted thoroughly with 40% MeOH/CHCl3 and filtered. This was repeated three times. The combined filtrates were concentrated and azeotroped 3×with toluene to provide 5-bromo-3-fluoropyridine-2-carboxylic acid that gave a mass ion (ES+) of 218.1 for M+H+(79Br).

Workup

  1. concentrationThe solution was concentrated in vacuo
  2. customazeotroped 3×with toluene
  3. extractionThe residue was extracted thoroughly with 40% MeOH/CHCl3
  4. filtrationfiltered
  5. concentrationThe combined filtrates were concentrated
  6. customazeotroped 3×with toluene

Sources & evidence

ORD record
ord-7d086800e4a9487c8937abac65d04e93
Source dataset
uspto-grants-2007_01
Patent number
US07163951B2

Reaction notes

Loading…