N-bromobutanimide → 2-Formyl-4,5-dimethoxybenzoic acid

HRID 1060577

Reaction equation

HRID 1060577 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[C:5]2[C:9](=[CH:10][C:11]=1[O:12][CH3:13])[C:8](=[O:14])[O:7][CH2:6]2.BrN1C(=[O:21])CCC1=O>C(Cl)(Cl)(Cl)Cl.C(OOC(=O)C1C=CC=CC=1)(=O)C1C=CC=CC=1>[CH:6]([C:5]1[CH:4]=[C:3]([O:2][CH3:1])[C:11]([O:12][CH3:13])=[CH:10][C:9]=1[C:8]([OH:7])=[O:14])=[O:21]

Participants

5

Reactant 2

HCID 67184N-bromobutanimideHCID 2304605,6-Dimethoxy-3H-isobenzofuran-1-one

Product 1

HCID 71762072-Formyl-4,5-dimethoxybenzoic acidYield 60%

Reagents, catalysts & solvents 2

HCID 7187Benzoyl PeroxideCatalystHCID 5943Carbon TetrachlorideSolvent

Procedure

A mixture of 5,6-dimethoxy-3H-isobenzofuran-1-one (10 g, 51.5 mmoles), obtained as described in example 1, under N2 in CCl4 (250 ml), N-bromo-succinimide (13.88 g, 77.25 mmoles) and benzoyl peroxide (320 mg, 1.23 mmoles) was kept under reflux for 2 hours, then cooled, filtered and washed with a 10% Na2SO3 solution (200 ml), then with water, anhydrified and brought to dryness. The residue was taken up with 5% HCl (100 ml) and kept under reflux for 4 hours, then the solution was cooled, basified with NaOH, washed with ethyl acetate and slowly re-acidified to give a precipitate which was filtered, washed with water, dried on P2O5 under vacuum to give 6.43 g of the title compound (yield: 60%).

Workup

  1. customobtained
  2. temperatureunder reflux for 2 hours
  3. temperaturecooled
  4. filtrationfiltered
  5. washwashed with a 10% Na2SO3 solution (200 ml)
  6. temperatureunder reflux for 4 hours
  7. temperaturethe solution was cooled
  8. washwashed with ethyl acetate
  9. customslowly re-acidified to give a precipitate which
  10. filtrationwas filtered
  11. washwashed with water
  12. customdried on P2O5 under vacuum

Sources & evidence

ORD record
ord-3dd58c7327334a03917835ac453d139d
Source dataset
uspto-grants-2003_02
Patent number
US06525055B1

Linked notes

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