1-Bromopentane → 3-Amino-4-methoxybenzoic acid

HRID 850450Notes

Reaction equation

HRID 850450 reaction equation
[CH3:1][O:2][C:3]1[CH:11]=[CH:10][C:6]([C:7]([OH:9])=[O:8])=[CH:5][C:4]=1[N+:12]([O-])=O.C(=O)([O-])[O-].[K+].[K+].C(Br)CCCC>CN(C=O)C>[NH2:12][C:4]1[CH:5]=[C:6]([CH:10]=[CH:11][C:3]=1[O:2][CH3:1])[C:7]([OH:9])=[O:8]

Participants

5

Reactant 3

HCID 80571-BromopentaneHCID 11430Potassium CarbonateHCID 666404-Methoxy-3-nitrobenzoic acid

Product 1

HCID 178233-Amino-4-methoxybenzoic acidYield 140.8%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Conditions

Temperature
100 °C

Procedure

4Methoxy-3-nitrobenzoic acid (5 g, 25.4 mmol), DMF (30 ml), potassium carbonate (5.53 g, 40 mmol) and pentyl bromide (4 ml, 32.3 mmol) were mixed, and this solution was stirred at 100° C. for 1.5 hours. The reaction mixture was filtered to remove the inorganic salt, and DMF was evaporated under reduced pressure. Ethyl acetate (100 ml) was added to the obtained residue. The mixture was washed 3 times with saturated brine (30 ml) and dried over anhydrous magnesium sulfate. The drying agent was filtered off, and the filtrate was concentrated under reduced pressure. Ethanol (150 ml) and 10% palladium-carbon catalyst (0.5 g) were added to the obtained residue, and the mixture was stirred at room temperature for 5.5 hours in a stream of hydrogen. The palladium-carbon catalyst was filtered off, and the filtrate was concentrated under reduced pressure. The obtained residue was purified by column chromatography (hexane/ethyl acetate=3/1) to give 3-amino -4-methoxybenzoic acid (5.98 g, 99% in 2 steps) as colorless crystals.

Workup

  1. filtrationThe reaction mixture was filtered
  2. customto remove the inorganic salt, and DMF
  3. customwas evaporated under reduced pressure
  4. additionEthyl acetate (100 ml) was added to the obtained residue
  5. washThe mixture was washed 3 times with saturated brine (30 ml)
  6. dry with materialdried over anhydrous magnesium sulfate
  7. filtrationThe drying agent was filtered off
  8. concentrationthe filtrate was concentrated under reduced pressure
  9. additionEthanol (150 ml) and 10% palladium-carbon catalyst (0.5 g) were added to the obtained residue
  10. stirringthe mixture was stirred at room temperature for 5.5 hours in a stream of hydrogen
  11. filtrationThe palladium-carbon catalyst was filtered off
  12. concentrationthe filtrate was concentrated under reduced pressure
  13. customThe obtained residue was purified by column chromatography (hexane/ethyl acetate=3/1)

Sources & evidence

ORD record
ord-db485c985caa464abb148e6bfce41e58
Source dataset
uspto-grants-2000_01
Patent number
US06017919

Reaction notes

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