Hydrochloric Acid → 4-oxo-3,4-dihydro-2H-1-benzopyran-2-carboxylic acid

HRID 1599395Notes

Reaction equation

HRID 1599395 reaction equation
[OH:1][C:2]1[CH:14]=[CH:13][CH:12]=[CH:11][C:3]=1[C:4]([CH:6]=[CH:7][C:8]([OH:10])=[O:9])=[O:5].Cl>C(=O)([O-])[O-].[Na+].[Na+]>[O:5]=[C:4]1[C:3]2[CH:11]=[CH:12][CH:13]=[CH:14][C:2]=2[O:1][CH:7]([C:8]([OH:10])=[O:9])[CH2:6]1

Participants

4

Procedure

A solution of 3-(2-hydroxybenzoyl)acrylic acid (3.02 g) in aqueous sodium carbonate (5%, 55 ml) was stirred at room temperature for 15 hours, acidified with 2N HCl and extracted with ethyl acetate. The ethyl acetate layer was washed with water, dried (MgSO4) and then treated with activated charcoal, after which the solvent was distilled off, to yield 2,3-dihydro-4-oxo-4H-1-benzopyran-2-carboxylic acid (2.01 g, 67%), which was then recrystallized from ethyl acetate-hexane to yield colorless prisms having a melting point of 170° to 171° C.

Workup

  1. extractionextracted with ethyl acetate
  2. washThe ethyl acetate layer was washed with water
  3. dry with materialdried (MgSO4)
  4. additiontreated with activated charcoal
  5. distillationafter which the solvent was distilled off

Sources & evidence

ORD record
ord-8c2b7892f5f3434db05a17fd1a16065d
Source dataset
uspto-grants-1998_04
Patent number
US05741784

Reaction notes

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