Lithium Hydroxide → 5-fluoro-2-(1H-pyrazol-5-yl)benzoic acid

HRID 1524909Notes

Reaction equation

HRID 1524909 reaction equation
[F:1][C:2]1[CH:3]=[CH:4][C:5]([C:12]2[NH:16][N:15]=[CH:14][CH:13]=2)=[C:6]([CH:11]=1)[C:7]([O:9]C)=[O:8].[Li+].[OH-]>CCO>[F:1][C:2]1[CH:3]=[CH:4][C:5]([C:12]2[NH:16][N:15]=[CH:14][CH:13]=2)=[C:6]([CH:11]=1)[C:7]([OH:9])=[O:8]

Participants

4

Reactant 2

HCID 3939Lithium HydroxideHCID 67086678methyl 5-fluoro-2-(1H-pyrazol-5-yl)benzoate

Product 1

HCID 670868915-fluoro-2-(1H-pyrazol-5-yl)benzoic acidYield 44%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A solution of methyl 5-fluoro-2-(1H-pyrazol-5-yl)benzoate (415 mg, 1.9 mmol) in EtOH (10 ml) was treated with 4.0 eq of LiOH and stirred and monitored for two hours until the reaction was complete. The reaction mixture was then made to pH=5, and then the solution concentrated under reduced pressure, during which time a ppt formed. The solution was concentrated to minimum volume and cooled in ice, filtered and washed with ice water to give 5-fluoro-2-(1H-pyrazol-5-yl)benzoic acid (172 mg, 44%). 1H NMR (400 MHz, DMSO-d6): 13.03 (s, 1H), 7.71 (d, J=2.0 Hz, 1H), 7.67 (dd, J=8.3, 5.6 Hz, 1H), 7.37 (td, J=8.6, 2.9 Hz, 2H), 6.44 (d, J=2.2 Hz, 1H).

Workup

  1. concentrationthe solution concentrated under reduced pressure, during which time a ppt
  2. customformed
  3. concentrationThe solution was concentrated to minimum volume
  4. temperaturecooled in ice
  5. filtrationfiltered
  6. washwashed with ice water

Sources & evidence

ORD record
ord-dbe478b90f0f40799a86d8ffbf8e4205
Source dataset
uspto-grants-2015_07
Patent number
US09079911B2

Reaction notes

Loading…