2',4'-Dihydroxyacetophenone → 7-Hydroxy-4-benzopyrone

HRID 333038

Reaction equation

HRID 333038 reaction equation
[OH:1][C:2]1[CH:7]=[C:6]([OH:8])[CH:5]=[CH:4][C:3]=1[C:9](=[O:11])[CH3:10].[CH:12](OCC)(OCC)OCC.Cl(O)(=O)(=O)=O>CCOCC>[OH:8][C:6]1[CH:7]=[C:2]2[C:3]([C:9](=[O:11])[CH:10]=[CH:12][O:1]2)=[CH:4][CH:5]=1

Participants

5

Reactant 3

HCID 69902',4'-DihydroxyacetophenoneHCID 24247Perchloric AcidHCID 31214Ethyl orthoformate

Product 1

HCID 54092797-Hydroxy-4-benzopyroneYield 53.2%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Procedure

To a round bottomed flask, 0.26 mol of 2′,4′-dihydroxyacetophenone was added and mixed thoroughly with 232 mL of triethyl orthoformate. Then 26.4 mL of perchloric acid was dropped slowly into the resultant mixture. After 30 min reaction, 300 mL ether was added, and solids were precipitated. Following sucking filtration, the dried solids were transferred into a 1000 mL round bottomed flask, and refluxed for 2 hours after 250 mL hot water was added. Sucking filtration was conducted again, and then 22.69 g of 7-hydroxychromone was obtained by recrystallization with ethanol, with a yield of 53.2% and MS m/z (M)162.

Workup

  1. additionwas added
  2. customsolids were precipitated
  3. filtrationfiltration
  4. customthe dried solids were transferred into a 1000 mL round bottomed flask
  5. temperaturerefluxed for 2 hours after 250 mL hot water
  6. additionwas added
  7. filtrationSucking filtration

Sources & evidence

ORD record
ord-34c7645a78fd4fd8bd6cdfc84e744fcc
Source dataset
uspto-grants-2014_11
Patent number
US08877949B2

Linked notes

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