Acetic Acid → HCID 59651980, compound

HRID 221847Notes

Reaction equation

HRID 221847 reaction equation
C[O:2][C:3]1[CH:8]=[CH:7][C:6]([C:9](=[O:15])[CH2:10][CH2:11][C:12]([OH:14])=[O:13])=[C:5]([CH3:16])[CH:4]=1.[C:17](O)(=O)[CH3:18].Br>C(O)C>[CH2:17]([O:14][C:12](=[O:13])[CH2:11][CH2:10][C:9]([C:6]1[CH:7]=[CH:8][C:3]([OH:2])=[CH:4][C:5]=1[CH3:16])=[O:15])[CH3:18]

Participants

5

Reactant 3

HCID 176Acetic AcidHCID 260Hydrogen BromideHCID 2876244-(4-methoxy-2-methylphenyl)-4-oxobutanoic acid

Product 1

HCID 59651980HCID 59651980, compoundYield 75%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Conditions

Temperature
130 °C

Procedure

A mixture of 4-(4-methoxy-2-methyl-phenyl)-4-oxo-butyric acid (2 g, 9 mmol), acetic acid (30 mL) and 48% aqueous HBr (10 mL) was heated at 130° C. for 5.5 h. The reaction was cooled to rt and concentrated at reduced pressure and azeotrope twice with benzene to give a crude residue. The crude residue was dissolved in ethanol (25 mL) and added amberlyst then heated at 90° C. for 18 h. The reaction was filtered over celite and evaporated ethanol at reduced pressure then quenched with water and extracted twice with methylene chloride to obtain 4-(4-hydroxy-2-methyl-phenyl)-4-oxo-butyric acid ethyl ester (1.6 g, 75%). The crude material was used for the next reaction without purification.

Workup

  1. temperatureThe reaction was cooled to rt
  2. concentrationconcentrated at reduced pressure and azeotrope twice with benzene
  3. customto give a crude residue
  4. additionadded
  5. temperatureamberlyst then heated at 90° C. for 18 h
  6. filtrationThe reaction was filtered over celite
  7. customevaporated ethanol at reduced pressure
  8. customthen quenched with water
  9. extractionextracted twice with methylene chloride

Sources & evidence

ORD record
ord-7b73112287a14c1a88125341419ebdf1
Source dataset
uspto-grants-2012_06
Patent number
US08207168B2

Reaction notes

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