3,5-Dihydroxybenzoic Acid → 3,5-Diacetoxybenzoic Acid

HRID 1381886Notes

Reaction equation

HRID 1381886 reaction equation
[OH:1][C:2]1[CH:3]=[C:4]([CH:8]=[C:9]([OH:11])[CH:10]=1)[C:5]([OH:7])=[O:6]>C(OC(=O)C)(=O)C.OS(O)(=O)=O>[C:2]([O:1][C:2]1[CH:3]=[C:4]([CH:8]=[C:9]([O:11][C:5](=[O:6])[CH3:4])[CH:10]=1)[C:5]([OH:7])=[O:6])(=[O:1])[CH3:10]

Participants

4

Reactant 1

HCID 74243,5-Dihydroxybenzoic Acid

Product 1

HCID 5398693,5-Diacetoxybenzoic Acid

Reagents, catalysts & solvents 2

HCID 1118Sulfuric AcidCatalystHCID 7918Acetic AnhydrideSolvent

Procedure

50 g of 3,5-dihydroxybenzoic acid are suspended in 132.2 g of acetic anhydride and heated to 50°. After the addition of 15 drops of concentrated H2SO4, the resulting solution is stirred for 1 hour at 60°. The reaction mixture is poured onto ice and extracted with CH2Cl2. The combined organic phases are washed 3 times with H2O, dried over Na2SO4 and concentrated by evaporation. The residue is crystallised from ether and yields 3,5-diacetoxybenzoic acid having a melting point of 140°-145°.

Workup

  1. temperatureheated to 50°
  2. additionThe reaction mixture is poured onto ice
  3. extractionextracted with CH2Cl2
  4. washThe combined organic phases are washed 3 times with H2O
  5. dry with materialdried over Na2SO4
  6. concentrationconcentrated by evaporation
  7. customThe residue is crystallised from ether

Sources & evidence

ORD record
ord-0a6ceee8e6a84e08a959326a3f682429
Source dataset
uspto-grants-1989_02
Patent number
US04804661

Reaction notes

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