Sulfuric Acid → 2-Iodo-4-methoxybenzoic acid

HRID 375870

Reaction equation

HRID 375870 reaction equation
S(=O)(=O)(O)O.[CH3:6][O:7][C:8]1[CH:9]=[C:10](N)[C:11](=[CH:15][CH:16]=1)[C:12]([OH:14])=[O:13].N([O-])=O.[Na+].[Na+].[I-:23]>O>[I:23][C:10]1[CH:9]=[C:8]([O:7][CH3:6])[CH:16]=[CH:15][C:11]=1[C:12]([OH:14])=[O:13]

Participants

6

Reactant 4

HCID 1118Sulfuric AcidHCID 5238Sodium IodideHCID 3510102-Amino-4-methoxybenzoic acidHCID 23668193Sodium Nitrite

Product 1

HCID 128221822-Iodo-4-methoxybenzoic acidYield 60.1%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent2×

Procedure

To a mixture of 50% sulfuric acid (150 ml) and 4-methoxyanthranilic acid (12 g) at 5°-10° C. was added sodium nitrite (5.5 g) in water, followed 10 minutes later by NaI (16.5 g) in water (30-50 ml). The reaction mixture was warmed to room temperature and stirred for 2 hours, then was heated at 60°-70° C. for 10 minutes, followed by stirring at room temperature for 1 hour. The reaction mixture was extracted with ether (4×125 ml) and the combined ether extracts were washed with water (50 ml×2), dried over MgSO4, filtered and evaporated. The residue was purified by column chromatography on silica gel eluting with ether to afford 12 g of 2-iodo-4-methoxybenzoic acid.

Workup

  1. temperaturewas heated at 60°-70° C. for 10 minutes
  2. stirringby stirring at room temperature for 1 hour
  3. extractionThe reaction mixture was extracted with ether (4×125 ml)
  4. washthe combined ether extracts were washed with water (50 ml×2)
  5. dry with materialdried over MgSO4
  6. filtrationfiltered
  7. customevaporated
  8. customThe residue was purified by column chromatography on silica gel eluting with ether

Sources & evidence

ORD record
ord-ec526ee1a2af4b03a1b9c11234fdc2cf
Source dataset
uspto-grants-1996_01
Patent number
US05488055

Linked notes

Loading…