Methanol → 2-Fluoro-5-methoxy-4-nitrobenzoic acid

HRID 1881026Notes

Reaction equation

HRID 1881026 reaction equation
[F:1][C:2]1[CH:10]=[C:9]([N+:11]([O-:13])=[O:12])[C:8](F)=[CH:7][C:3]=1[C:4]([OH:6])=[O:5].[OH-:15].[K+].[CH3:17]O>>[F:1][C:2]1[CH:10]=[C:9]([N+:11]([O-:13])=[O:12])[C:8]([O:15][CH3:17])=[CH:7][C:3]=1[C:4]([OH:6])=[O:5]

Participants

4

Reactant 3

HCID 887MethanolHCID 14797Potassium HydroxideHCID 2463752,5-Difluoro-4-nitrobenzoic acid

Product 1

HCID 579556142-Fluoro-5-methoxy-4-nitrobenzoic acidYield 90%

Procedure

To a solution of 2,5-difluoro-4-nitrobenzoic acid (55 g, 291 mmol) in methanol (800 mL) at 80° C. was added a methanolic solution of potassium hydroxide (48.9 g, 873 mmol in 175 mL MeOH, pre-heated at 80° C. to dissolve) dropwise in a period of 2 h using an addition funnel. The reaction mixture was continuously stirred for 1 h after addition was completed. It was then concentrated, acidified with HCl to pH=1-2. The reaction mixture was then vigorously stirred overnight. Fine powder was filtered, washed with more water and dried to give the product as light yellow powder (55.4 g, 90%). 1H NMR (400 MHz, DMSO-d6) δ ppm 3.95 (s, 3 H) 7.66 (d, J=4 Hz, 1 H) 8.01 (d, J=8 Hz, 1 H). [M+H] calc'd for C8H6FNO5, 216; found 216.

Workup

  1. additionafter addition
  2. concentrationIt was then concentrated
  3. customvigorously stirred overnight
  4. filtrationFine powder was filtered
  5. washwashed with more water
  6. customdried

Sources & evidence

ORD record
ord-e0df39e41b304d2eaedabf5245f90d07
Source dataset
uspto-grants-2012_11
Patent number
US08318727B2

Reaction notes

Loading…