Dimethyl Sulfate → Methyl 5-isopropyl-2,4-dimethoxybenzoate

HRID 389954Notes

Reaction equation

HRID 389954 reaction equation
[OH:1][C:2]1[CH:11]=[C:10](O)[C:9]([CH:13]([CH3:15])[CH3:14])=[CH:8][C:3]=1[C:4]([O:6][CH3:7])=[O:5].[C:16](=O)([O-])[O-].[K+].[K+].S([O:27][CH3:28])(OC)(=O)=O>C(#N)C>[CH:13]([C:9]1[C:10]([O:27][CH3:28])=[CH:11][C:2]([O:1][CH3:16])=[C:3]([CH:8]=1)[C:4]([O:6][CH3:7])=[O:5])([CH3:15])[CH3:14]

Participants

5

Reactant 3

HCID 6497Dimethyl SulfateHCID 11430Potassium CarbonateHCID 59167875Methyl 2,4-dihydroxy-5-(propan-2-yl)benzoate

Product 1

HCID 59263169Methyl 5-isopropyl-2,4-dimethoxybenzoateYield 74%

Reagents, catalysts & solvents 1

HCID 6342AcetonitrileSolvent

Procedure

A mixture of methyl 2,4-dihydroxy-5-isopropylbenzoate (420 mg, 2.0 mmol) and anhydrous potassium carbonate (662 mg, 4.8 mmol) in acetonitrile (10 ml) was treated with dimethyl sulphate (0.4 ml, 4.2 mmol) and the mixture was stirred at room temperature for 16 hours and then held at reflux for 6 hours. Upon cooling to room temperature the solvent was removed in vacuo and the residue acidified by the addition of 2M hydrochloric acid (10 ml). The solid material was collected by suction filtration, rinsed with water (2×10 ml) and sucked dry under reduced pressure to afford methyl 5-isopropyl-2,4-dimethoxybenzoate (350 mg, 74%) as a colourless solid. 1H NMR (DMSO-d6) 7.53 (1H, s), 6.67 (1H, s), 3.92 (3H, s), 3.86 (3H, s), 3.75 (3H, s), 3.13 (1H, m), 1.14 (6H, d). MS: [M+Na]+ 261.

Workup

  1. temperatureat reflux for 6 hours
  2. temperatureUpon cooling to room temperature the solvent
  3. customwas removed in vacuo
  4. additionthe residue acidified by the addition of 2M hydrochloric acid (10 ml)
  5. filtrationThe solid material was collected by suction filtration
  6. washrinsed with water (2×10 ml)
  7. customsucked dry under reduced pressure

Sources & evidence

ORD record
ord-c14e4342fc81416c8b30593b96bffc2a
Source dataset
uspto-grants-2013_02
Patent number
US08383619B2

Reaction notes

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