Potassium Hydroxide → 4-Methoxyphthalic acid

HRID 334894Notes

Reaction equation

HRID 334894 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[C:5]([C:13]([O:15]C)=[O:14])[C:6](=[CH:11][CH:12]=1)[C:7]([O:9]C)=[O:8].[OH-].[K+]>CO.O>[CH3:1][O:2][C:3]1[CH:4]=[C:5]([C:13]([OH:15])=[O:14])[C:6](=[CH:11][CH:12]=1)[C:7]([OH:9])=[O:8]

Participants

5

Reactant 2

HCID 14797Potassium HydroxideHCID 736307Dimethyl 4-methoxyphthalate

Product 1

HCID 746654-Methoxyphthalic acidYield 101.3%

Reagents, catalysts & solvents 2

HCID 887MethanolSolvent2×HCID 962WaterSolvent

Procedure

A solution of dimethyl 4-methoxyphthalate (36.75 g, 0.16 mol) in methanol (100 ml) was treated with a solution of potassium hydroxide (28.0 g, 0.5 mol) in water (50 ml) and the mixture was stirred and held at reflux for 4 hours. Upon cooling to room temperature the methanol was removed in vacuo and the mixture acidified to pH 2 or below by the addition of 5M hydrochloric acid. The solid material was filtered off, washed with water and sucked dry under reduced pressure overnight to afford 4-methoxyphthalic acid (31.8 g, 99%) as an off white solid. 1H NMR (DMSO-d6) 12.90 (2H, br s), 7.74 (1H, d), 7.12-7.05 (2H, m), 3.84 (3H, s). MS: [M+H]+ 197.

Workup

  1. temperatureat reflux for 4 hours
  2. customwas removed in vacuo
  3. additionthe mixture acidified to pH 2 or below by the addition of 5M hydrochloric acid
  4. filtrationThe solid material was filtered off
  5. washwashed with water
  6. customsucked dry under reduced pressure overnight

Sources & evidence

ORD record
ord-edec8e5d32904a4ca5ac6dde72d635aa
Source dataset
uspto-grants-2014_11
Patent number
US08883790B2

Reaction notes

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