Oxalic Acid → 2,5-Dimethyl-3-furoic acid

HRID 972952

Reaction equation

HRID 972952 reaction equation
C(O)(=O)C(O)=O.[C:7]([CH:12]([CH2:16][C:17](=[O:19])[CH3:18])[C:13](=O)[CH3:14])([O:9]CC)=[O:8].[OH-].[K+]>CO>[CH3:14][C:13]1[O:19][C:17]([CH3:18])=[CH:16][C:12]=1[C:7]([OH:9])=[O:8]

Participants

5

Reactant 3

HCID 971Oxalic AcidHCID 14797Potassium HydroxideHCID 3084847Ethyl 2-acetyl-4-oxovalerate

Product 1

HCID 694652,5-Dimethyl-3-furoic acid

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

To a stirred and refluxing solution of ethyl sodioacetoacetate (0.5 mole, 78g.) and sodium iodide (1g.) in dry acetone (250 ml.) was added chloroactone (0.54 mol. 50g.) over a period of ten minutes. After one hour the acetone was distilled from the reaction mixture and the residue was diluted with 400 ml. water. The preciptated oil was extracted with ether and the ether removed to yield the intermediate 3-carbethoxy-2,5-hexanedione (75g.). The intermediate (26.4g.) was cyclized by heating under reflux over 5 g. anhydrous oxalic acid for 11/4 hours. The crude ester was saponified by heating under reflux for 45 minutes with potassium hydroxide (26g.) in methanol (200 ml.). The methanol was removed, the residue dissolved in water and the solution acidified to yield 2,5-dimethyl-3-furoic acid (18g.), m.p. 130°-133°.

Workup

  1. temperatureby heating
  2. temperatureunder reflux over 5 g
  3. custom4 hours
  4. temperatureby heating
  5. customThe methanol was removed
  6. dissolutionthe residue dissolved in water

Sources & evidence

ORD record
ord-91d4de1fcaaa410e9167deae42283301
Source dataset
uspto-grants-1977_10
Patent number
US04054585

Linked notes

Loading…