Sulfuric Acid → Methyl 3-amino-5-hydroxy-4-iodobenzoate

HRID 1990830

Reaction equation

HRID 1990830 reaction equation
[NH2:1][C:2]1[CH:3]=[C:4]([CH:8]=[C:9]([OH:12])[C:10]=1[I:11])[C:5]([OH:7])=[O:6].S(=O)(=O)(O)O.[C:18](=O)([O-])O.[Na+]>CO>[CH3:18][O:6][C:5](=[O:7])[C:4]1[CH:8]=[C:9]([OH:12])[C:10]([I:11])=[C:2]([NH2:1])[CH:3]=1

Participants

5

Reactant 3

HCID 1118Sulfuric AcidHCID 516892Sodium BicarbonateHCID 684584523-Amino-5-hydroxy-4-iodobenzoic acid

Product 1

HCID 68458438Methyl 3-amino-5-hydroxy-4-iodobenzoateYield 33%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

To a solution of 3-amino-5-hydroxy-4-iodo-benzoic acid (0.20 g, 0.72 mmol, 1.0 equiv) in methanol (5 mL) was added conc. sulfuric acid (0.20 mL, 0.035 g, 0.36 mmol, 0.5 equiv) and the reaction mixture heated to reflux. After 2 h, the reaction mixture was poured on ice, the pH adjusted to 9 by addition of a sat. solution of sodium hydrogencarbonate and extracted with ethyl acetate (2×50 mL). The combined organic phases were dried over MgSO4, concentrated by evaporation under reduced pressure and the crude material purified with column chromatography on silica eluting with hexane/ethyl acetate (1:1) providing 0.07 g (33%) of the title compound. 1H NMR (250 MHz, DMSO): δ 3.78 (s, 3H), 5.45 (br s, 2H), 6.68 (s, 1H), 6.85 (s, 1H), 10.32 (br s, 1H). MS (EI): 293.0 [M]+.

Workup

  1. temperaturethe reaction mixture heated to reflux
  2. additionthe reaction mixture was poured on ice
  3. extractionextracted with ethyl acetate (2×50 mL)
  4. dry with materialThe combined organic phases were dried over MgSO4
  5. concentrationconcentrated by evaporation under reduced pressure
  6. customthe crude material purified with column chromatography on silica eluting with hexane/ethyl acetate (1:1)

Sources & evidence

ORD record
ord-615f6a5a3c5c4591af5883cfb2829b49
Source dataset
uspto-grants-2010_01
Patent number
US07645753B2

Linked notes

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