Potassium Hydroxide → 4-Allyloxy-2-hydroxy-5-isopropylbenzoic acid

HRID 1182803Notes

Reaction equation

HRID 1182803 reaction equation
[OH-].[K+].[CH2:3]([O:6][C:7]1[C:16]([CH:17]([CH3:19])[CH3:18])=[CH:15][C:10]([C:11]([O:13]C)=[O:12])=[C:9]([OH:20])[CH:8]=1)[CH:4]=[CH2:5]>CO.O>[CH2:3]([O:6][C:7]1[C:16]([CH:17]([CH3:18])[CH3:19])=[CH:15][C:10]([C:11]([OH:13])=[O:12])=[C:9]([OH:20])[CH:8]=1)[CH:4]=[CH2:5]

Participants

5

Reactant 2

HCID 14797Potassium HydroxideHCID 58236466Methyl 4-allyloxy-2-hydroxy-5-isopropylbenzoate

Product 1

HCID 582364674-Allyloxy-2-hydroxy-5-isopropylbenzoic acidYield 96.5%

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 962WaterSolvent

Procedure

Aqueous potassium hydroxide (50% w/v, 0.2 ml) was added to a suspension of methyl 4-allyloxy-2-hydroxy-5-isopropylbenzoate (313 mg, 1.25 mmol) in methanol (6 ml) and water (2 ml) and the mixture was stirred and held at reflux for 4 hours. Upon cooling to room temperature the organic 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 4-allyloxy-2-hydroxy-5-isopropylbenzoic acid (285 mg, 96%) as a colourless solid. 1H NMR (DMSO-d6) 13.50 (1H, br s), 11.40 (1H, s), 7.55 (1H, s), 6.51 (1H, s), 6.06 (1H, m), 5.42 (1H, dm), 5.28 (1H, dm), 4.64 (2H, m), 3.17 (1H, m), 1.17 (6H, d). MS: [M+H]+ 237.

Workup

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

Sources & evidence

ORD record
ord-b159360584c4490bb3b761a969ce3cf9
Source dataset
uspto-grants-2014_03
Patent number
US08664218B2

Reaction notes

Loading…