Lithium hydroxide, monohydrate → 4-Fluoro-3-methoxybenzoic acid

HRID 1243217Notes

Reaction equation

HRID 1243217 reaction equation
C[O:2][C:3](=[O:13])[C:4]1[CH:9]=[CH:8][C:7]([F:10])=[C:6]([O:11][CH3:12])[CH:5]=1.O.[OH-].[Li+]>O1CCCC1.O>[F:10][C:7]1[CH:8]=[CH:9][C:4]([C:3]([OH:13])=[O:2])=[CH:5][C:6]=1[O:11][CH3:12]

Participants

5

Reactant 2

HCID 168937Lithium hydroxide, monohydrateHCID 592847Methyl 4-fluoro-3-methoxybenzoate

Product 1

HCID 5984364-Fluoro-3-methoxybenzoic acid

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8028TetrahydrofuranSolvent

Procedure

4-Fluoro-3-methoxybenzoic acid methyl ester (2.55 g, 13.85 mmol) (from Example 34a supra) was dissolved in a mixture of tetrahydrofuran (140 mL) and water (70 mL). Lithium hydroxide monohydrate (5.8 g, 138.5 mmol) was added and the mixture was heated at reflux for 3.5 hours. After quenching with 1 N aqueous hydrochloric acid (150 mL), the solution was extracted with dichloromethane. The phases were separated and the organic layer was dried over anhydrous sodium sulfate. Concentration under reduced pressure gave 4-fluoro-3-methoxybenzoic acid as an off-white solid. (Yield 2.26 g, 96%).

Workup

  1. temperaturethe mixture was heated
  2. temperatureat reflux for 3.5 hours
  3. customAfter quenching with 1 N aqueous hydrochloric acid (150 mL)
  4. extractionthe solution was extracted with dichloromethane
  5. customThe phases were separated
  6. dry with materialthe organic layer was dried over anhydrous sodium sulfate
  7. concentrationConcentration under reduced pressure

Sources & evidence

ORD record
ord-8965fad0d61e4d788294bca84dced858
Source dataset
uspto-grants-2006_10
Patent number
US07115740B2

Reaction notes

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