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

HRID 243850Notes

Reaction equation

HRID 243850 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-eafe26603ad84ba494e4500fdf4b867d
Source dataset
uspto-grants-2014_02
Patent number
US08653263B2

Reaction notes

Loading…