Acetic Acid → HCID 21466966, compound

HRID 440124Notes

Reaction equation

HRID 440124 reaction equation
Cl.C(C1(C(C#N)C#N)[C:9]2[CH:10]=[C:11]([O:14]C)[CH:12]=[CH:13][C:8]=2[O:7][CH2:6][CH2:5]1)#N.CC[O:23][CH2:24][CH3:25].[OH2:26].[C:27]([OH:30])(=[O:29])[CH3:28]>>[C:27]([C:28]1([CH2:25][C:24]([OH:26])=[O:23])[C:13]2[CH:12]=[C:11]([OH:14])[CH:10]=[CH:9][C:8]=2[O:7][CH2:6][CH2:5]1)([OH:30])=[O:29]

Participants

5

Reactant 4

HCID 176Acetic AcidHCID 313Hydrochloric AcidHCID 21466990HCID 21466990, compoundHCID 21584184Diethylether water

Product 1

HCID 21466966HCID 21466966, compound

Procedure

Concentrated hydrochloric acid is added to a mixture of 4-cyano-3,4-dihydro-6-methoxy-2H-1-benzopyran-4-malononitrile (42.76 g, 0.1688 mol) in acetic acid at 30° C. The reaction mixture is heated at reflux for three days, cooled and concentrated in vacuo to give a brown solid. The solid is stirred in an ether/water mixture, filtered, washed sequentially with ether and water and dried to obtain 4-carboxy-3,4-dihydro-6-hydroxy-2H-1-benzopyran-4-acetic acid as a gray solid (10.25 g) which is identified by 1H and 13CNMR spectral analyses.

Workup

  1. temperatureThe reaction mixture is heated
  2. temperatureat reflux for three days
  3. temperaturecooled
  4. concentrationconcentrated in vacuo
  5. customto give a brown solid
  6. filtrationfiltered
  7. washwashed sequentially with ether and water
  8. customdried

Sources & evidence

ORD record
ord-fae4579db34c4eb1a4e1f326e411109d
Source dataset
uspto-grants-1996_05
Patent number
US05516918

Reaction notes

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