Dimethyl Sulfate → 1,3-Dihydro-4-methoxy-1,3-dimethyl-2H-indol-2-one

HRID 1769

Reaction equation

HRID 1769 reaction equation
[OH:1][C:2]1[CH:10]=[CH:9][CH:8]=[C:7]2[C:3]=1[CH:4]([CH3:13])[C:5](=[O:12])[N:6]2[CH3:11].[C:14](=O)([O-])[O-].[K+].[K+].COS(OC)(=O)=O>CC(C)=O>[CH3:14][O:1][C:2]1[CH:10]=[CH:9][CH:8]=[C:7]2[C:3]=1[CH:4]([CH3:13])[C:5](=[O:12])[N:6]2[CH3:11]

Participants

5

Reactant 3

HCID 6497Dimethyl SulfateHCID 11430Potassium CarbonateHCID 196929451,3-dihydro-4-hydroxy-1,3-dimethyl-2H-indol-2-one

Product 1

HCID 196929551,3-Dihydro-4-methoxy-1,3-dimethyl-2H-indol-2-oneYield 86.2%

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

A slurry of 1,3-dihydro-4-hydroxy-1,3-dimethyl-2H-indol-2-one (50 g), milled potassium carbonate (60.1 g) and HPLC grade acetone (400 ml) was mechanically stirred at room temperature as dimethylsulfate (41.4 ml) was added dropwise. The addition funnel was replaced with a condenser and the slurry was refluxed for 18 hours. The K2CO3 was filtered off and washed well with acetone. Acetone was evaporated and the residue was purified by column chromatography to yield 46.5 g of an oil. The oil was dissolved in ether and placed in the refrigerator where, upon standing overnight, the product crystallized, m.p. 73°-74° C.

Workup

  1. additionwas added dropwise
  2. customThe addition funnel was replaced with a condenser
  3. temperaturethe slurry was refluxed for 18 hours
  4. filtrationThe K2CO3 was filtered off
  5. washwashed well with acetone
  6. customAcetone was evaporated
  7. customthe residue was purified by column chromatography

Sources & evidence

ORD record
ord-0f8c43802c60460ab93e17f76623a594
Source dataset
uspto-grants-1998_03
Patent number
US05726323

Linked notes

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