Methanol → Methyl 2,3-difluoro-4-methylbenzoate

HRID 883476Notes

Reaction equation

HRID 883476 reaction equation
[F:1][C:2]1[C:10]([F:11])=[C:9]([CH3:12])[CH:8]=[CH:7][C:3]=1[C:4]([OH:6])=[O:5].[CH3:13]O.S(=O)(=O)(O)O>>[CH3:13][O:5][C:4](=[O:6])[C:3]1[CH:7]=[CH:8][C:9]([CH3:12])=[C:10]([F:11])[C:2]=1[F:1]

Participants

4

Reactant 3

HCID 887MethanolHCID 1118Sulfuric AcidHCID 27741412,3-Difluoro-4-methylbenzoic acid

Product 1

HCID 55255640Methyl 2,3-difluoro-4-methylbenzoateYield 83.2%

Procedure

2,3-Difluoro-4-methyl-benzoic acid (10.0 g, 58.1 mmol) was dissolved in MeOH (200 mL, 6.0 mol) and sulfuric acid (1.00 mL, 19.0 mmol), and was heated at reflux overnight. The mixture was then cooled and concentrated under reduced pressure. The resulting residue was taken up in EtOAc and washed with saturated aqueous NaCl, dried over MgSO4, filtered and concentrated to yield 9.0 g of intermediate (7a) as a white solid. 1H-NMR (CDCl3): 7.61 (1H, t), 7.00 (1H, t), 3.93 (3H, s), 2.35 (3H, s).

Workup

  1. temperatureat reflux overnight
  2. temperatureThe mixture was then cooled
  3. concentrationconcentrated under reduced pressure
  4. washwashed with saturated aqueous NaCl
  5. dry with materialdried over MgSO4
  6. filtrationfiltered
  7. concentrationconcentrated

Sources & evidence

ORD record
ord-97972f6467ac4e9999f9f068d7e7cdb9
Source dataset
uspto-grants-2012_08
Patent number
US08236846B2

Reaction notes

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