Potassium Permanganate → 7-Bromo-3,3-dimethyl-2,3-dihydrobenzofuran-5-carboxylic acid

HRID 460289Notes

Reaction equation

HRID 460289 reaction equation
[Br:1][C:2]1[C:10]2[O:9][CH2:8][C:7]([CH3:12])([CH3:11])[C:6]=2[CH:5]=[C:4]([CH:13]=[O:14])[CH:3]=1.[O-:15][Mn](=O)(=O)=O.[K+]>CC(C)=O.O>[Br:1][C:2]1[C:10]2[O:9][CH2:8][C:7]([CH3:11])([CH3:12])[C:6]=2[CH:5]=[C:4]([C:13]([OH:15])=[O:14])[CH:3]=1

Participants

5

Reactant 2

HCID 516875Potassium PermanganateHCID 184454227-Bromo-3,3-dimethyl-2,3-dihydro-benzofuran-5-carbaldehyde

Product 1

HCID 220414067-Bromo-3,3-dimethyl-2,3-dihydrobenzofuran-5-carboxylic acidYield 64%

Reagents, catalysts & solvents 2

HCID 180AcetoneSolventHCID 962WaterSolvent

Procedure

A solution of 7-bromo-3,3-dimethyl-2,3-dihydro-benzofuran-5-carbaldehyde (14.61 g, 57.29 mmol) in acetone (80 mL) was added at room temperature to KMnO4 (9.05 g, 57.29 mmol) dissolved in water (200 mL). The reaction mixture was stirred at room temperature overnight filtered over celite then H2SO4 in water was added and the solution extracted with ethyl acetate. The organic layer was further washed with water and brine, dried over anhydrous magnesium sulfate, filtered and evaporated to give 9.9 g of 7-bromo-3,3-dimethyl-2,3-dihydro-benzofuran-5-carboxylic acid (64%). 1H NMR (300 MHz; CDCl3): 1.40 (s, 6H), 4.44 (s, 2H), 7.79 (s, 1H), 8.13 (s, 1H). c. 7-bromo-3,3-dimethyl-2,3-dihydro-benzofuran-5-carbaldehyde.

Workup

  1. filtrationfiltered over celite
  2. additionH2SO4 in water was added
  3. extractionthe solution extracted with ethyl acetate
  4. washThe organic layer was further washed with water and brine
  5. dry with materialdried over anhydrous magnesium sulfate
  6. filtrationfiltered
  7. customevaporated

Sources & evidence

ORD record
ord-d5791ae395814665b1e6dc8ebf1efea6
Source dataset
uspto-grants-2007_03
Patent number
US07196108B2

Reaction notes

Loading…