Hydrochloric Acid → Benzoic acid, 2,4-dimethoxy-, methyl ester

HRID 501784

Reaction equation

HRID 501784 reaction equation
OC1C=[C:9]([OH:11])[CH:8]=[CH:7][C:3]=1[C:4](O)=O.[C:12](=O)([O-])[O-].[K+].[K+].S([O:23][CH3:24])(OC)(=O)=O.Cl.[C:26]([O:29][CH2:30]C)(=[O:28])[CH3:27]>O.CN(C)C=O>[CH3:12][O:11][C:9]1[CH:8]=[C:7]([O:23][CH3:24])[CH:3]=[CH:4][C:27]=1[C:26]([O:29][CH3:30])=[O:28]

Participants

8

Reactant 5

HCID 313Hydrochloric AcidHCID 14912,4-Dihydroxybenzoic AcidHCID 6497Dimethyl Sulfate2×HCID 8857Ethyl AcetateHCID 11430Potassium Carbonate2×

Product 1

HCID 137451Benzoic acid, 2,4-dimethoxy-, methyl ester

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6228DimethylformamideSolvent

Conditions

Temperature
75 °C

Procedure

50 g of 2,4-dihydroxybenzoic acid, 269 g of potassium carbonate, 123 mL of dimethyl sulfate, and 500 mL of N,N-dimethylformamide were suspended together, and this suspension was stirred for 6.5 hours at 70 to 80° C. Further, 90 g of potassium carbonate and 61 mL of dimethyl sulfate were added to this suspension, which was stirred for another 4 hours at 110 to 115° C. This reaction mixture was added to a mixture of ethyl acetate and water, and adjusted to pH 2 with 6M hydrochloric acid, and then the organic phase was separated therefrom. After the resultant organic phase was washed with water and a saturated sodium chloride solution successively, the washed phase was dried over anhydrous magnesium sulfate, and the solvent was distilled out under reduced pressure. The resultant residue was purified by silica gel column chromatography [eluent; hexane:ethyl acetate=1:2] to yield 54 g of methyl 2,4-dimethoxybenzoate as yellow oil.

Workup

  1. stirringwas stirred for another 4 hours at 110 to 115° C
  2. customthe organic phase was separated
  3. washAfter the resultant organic phase was washed with water
  4. dry with materiala saturated sodium chloride solution successively, the washed phase was dried over anhydrous magnesium sulfate
  5. distillationthe solvent was distilled out under reduced pressure
  6. customThe resultant residue was purified by silica gel column chromatography [eluent; hexane:ethyl acetate=1:2]

Sources & evidence

ORD record
ord-fb59e1c798564fa39839988088ff206f
Source dataset
uspto-grants-2010_08
Patent number
US07772285B2

Linked notes

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