Dimethyl Sulfate → Methyl 4-bromo-3,5-dimethoxybenzoate

HRID 1454115Notes

Reaction equation

HRID 1454115 reaction equation
[Br:1][C:2]1[C:10](O)=[CH:9]C(C(O)=O)=[CH:4][C:3]=1[OH:12].[C:13](=O)([O-])[O-].[K+].[K+].S([O:24][CH3:25])(OC)(=O)=O.[C:26]([O:29][CH2:30]C)(=[O:28])[CH3:27]>>[Br:1][C:2]1[C:3]([O:12][CH3:13])=[CH:4][C:27]([C:26]([O:29][CH3:30])=[O:28])=[CH:9][C:10]=1[O:24][CH3:25]

Participants

5

Reactant 4

HCID 6497Dimethyl SulfateHCID 8857Ethyl AcetateHCID 11430Potassium CarbonateHCID 860234-Bromo-3,5-dihydroxybenzoic acid

Product 1

HCID 117713Methyl 4-bromo-3,5-dimethoxybenzoate

Conditions

Temperature
65 °C

Procedure

To a suspension of 4-bromo-3,5-dihydroxybenzoic acid (95.0 kg) in ethyl acetate (950 L) were added anhydrous potassium carbonate (270.8 kg) and dimethyl sulfate (174.7 kg). The mixture was heated at 50-80° C. for about 4 hours and partitioned by adding water. The organic layer was washed with water and saturated aqueous NaCl solution and concentrated under reduced pressure. The residue was suspended into methanol, stirred under heating and cooled. The crystalline precipitates were collected by filtration and dried to yield methyl 4-bromo-3,5-dimethoxybenzoate (98.8 kg) as pale yellow crystals.

Workup

  1. custompartitioned
  2. additionby adding water
  3. washThe organic layer was washed with water and saturated aqueous NaCl solution
  4. concentrationconcentrated under reduced pressure
  5. temperatureunder heating
  6. temperaturecooled
  7. customThe crystalline precipitates
  8. filtrationwere collected by filtration
  9. customdried

Sources & evidence

ORD record
ord-6f717bfc8cc1491dbf06b23c14eaf4a6
Source dataset
uspto-grants-2009_01
Patent number
US07476758B2

Reaction notes

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