Dimethyl Sulfate → 2,5-Dimethoxytoluene

HRID 2257118Notes

Reaction equation

HRID 2257118 reaction equation
[CH3:1][C:2]1[CH:8]=[C:7](O)[CH:6]=[CH:5][C:3]=1[OH:4].[C:10](=[O:13])([O-])[O-].[K+].[K+].S(OC)(O[CH3:20])(=O)=O>CC(C)=O>[CH3:20][O:4][C:3]1[CH:5]=[CH:6][C:7]([O:13][CH3:10])=[CH:8][C:2]=1[CH3:1]

Participants

5

Reactant 3

HCID 6497Dimethyl SulfateHCID 7253MethylhydroquinoneHCID 11430Potassium Carbonate

Product 1

HCID 905522,5-DimethoxytolueneYield 81.6%

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

A mixture of 12 g of methylhydroquinone, 45 g of potassium carbonate and 45 g of dimethyl sulphate in 300 ml of anhydrous acetone is heated to reflux for 4 days. After cooling, the reaction mixture is filtered and the filtrate is evaporated under vacuum. The residue is taken up in 150 ml of concentrated aqueous ammonia, the mixture is left stirring for 2 hours, diluted with water and extracted with DCM, the organic phase is dried over magnesium sulphate and the solvent is evaporated off under vacuum. The residue is chromatographed on silica H, eluting with a heptane/DCM (50:50; v/v) mixture. 12 g of the expected product are obtained.

Workup

  1. temperatureis heated
  2. temperatureto reflux for 4 days
  3. temperatureAfter cooling
  4. filtrationthe reaction mixture is filtered
  5. customthe filtrate is evaporated under vacuum
  6. waitthe mixture is left
  7. additiondiluted with water
  8. extractionextracted with DCM
  9. dry with materialthe organic phase is dried over magnesium sulphate
  10. customthe solvent is evaporated off under vacuum
  11. customThe residue is chromatographed on silica H
  12. washeluting with a heptane/DCM (50:50; v/v) mixture

Sources & evidence

ORD record
ord-cd2cade0ce8d457fa300ad4b18d63f74
Source dataset
uspto-grants-1997_08
Patent number
US05656648

Reaction notes

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