Toluene → 3,4-Dimethoxytoluene

HRID 849710Notes

Reaction equation

HRID 849710 reaction equation
CC1C=C(O)[C:5](=CC=1)[OH:6].[C:10]1([CH3:16])[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1.[OH-].[Na+].S(OC)([O:22][CH3:23])(=O)=O>O>[CH3:5][O:6][C:12]1[CH:11]=[C:10]([CH3:16])[CH:15]=[CH:14][C:13]=1[O:22][CH3:23]

Participants

6

Reactant 4

HCID 1140TolueneHCID 6497Dimethyl SulfateHCID 99584-MethylcatecholHCID 14798Sodium Hydroxide4×

Product 1

HCID 681263,4-Dimethoxytoluene

Reagents, catalysts & solvents 1

HCID 962WaterSolvent2×

Procedure

In a 1 L, 3-necked flask was placed 500.0 g of 4-methylcatechol (4.03 mole, 1.0 eq.), 808 mL of toluene (5 mole/L) and 404 mL of water (10 mole/L). The flask was fitted with an overhead mechanical stirrer, thermocouple probe and a dropping funnel. The dropping funnel was charged with 357.1 g of sodium hydroxide (8.86 mole, 2.2 eq.) dissolved in 748 mL of water (11.8 mole/L). Dimethyl sulfate (838 mL, 8.87 mole, 1.1 eq.) was added to the flask. The contents of the flask were stirred well and the sodium hydroxide solution was added slowly to the flask. The temperature of the reaction rose to 35° C., at which point the addition of sodium hydroxide was slowed, such that the temperature did not exceed 35° C. External cooling by means of a chilled water bath applied. After the addition of sodium hydroxide was complete, the flask was removed from the chilled water bath and stirred until the temperature of the mixture returned to room temperature (~1.5 hours). Stirring was stopped. The phases were separated. The aqueous phase was extracted with fresh toluene (150 mL). The combined organic phases were dried over anhydrous potassium carbonate, filtered and concentrated by fraction distillation at atmospheric pressure. The crude product was purified by vacuum fractional distillation to provide a total of 559.6 g of the desired product.

Workup

  1. customThe flask was fitted with an overhead mechanical stirrer
  2. customrose to 35° C., at which point
  3. customdid not exceed 35° C
  4. temperatureExternal cooling by means of a chilled water bath
  5. customthe flask was removed from the chilled water bath
  6. stirringstirred until the temperature of the mixture
  7. customreturned to room temperature
  8. custom(~1.5 hours)
  9. stirringStirring
  10. customThe phases were separated
  11. extractionThe aqueous phase was extracted with fresh toluene (150 mL)
  12. dry with materialThe combined organic phases were dried over anhydrous potassium carbonate
  13. filtrationfiltered
  14. concentrationconcentrated by fraction distillation at atmospheric pressure
  15. distillationThe crude product was purified by vacuum fractional distillation

Sources & evidence

ORD record
ord-71d39e28915541f19449cc64a82d199d
Source dataset
uspto-grants-2000_01
Patent number
US06013841

Reaction notes

Loading…