Methanol → 3,5-Diamino-2-methylbenzoic acid

HRID 399512Notes

Reaction equation

HRID 399512 reaction equation
[NH2:1][C:2]1[CH:3]=[C:4]([CH:8]=[CH:9][C:10]=1[NH2:11])[C:5]([OH:7])=[O:6].S(Cl)(Cl)=O.[CH3:16]O>>[NH2:1][C:2]1[CH:3]=[C:4]([CH:8]=[CH:9][C:10]=1[NH2:11])[C:5]([O:7][CH3:16])=[O:6]

Participants

4

Reactant 3

HCID 887MethanolHCID 24386Thionyl Chloride2×HCID 692633,4-Diaminobenzoic acid

Product 1

HCID 1355243,5-Diamino-2-methylbenzoic acidYield 93%

Procedure

3.0 g of 3,4-diaminobenzoic acid was suspended in methanol, and 1.86 ml of thionyl chloride was then added dropwise. Afterward, thionyl chloride was further added as much as 0.5 ml twice, and the suspension was then heated under reflux for 11 hours. Next, thionyl chloride and methanol were distilled off, and the residue was dissolved in methylene chloride, washed with a 0.5N aqueous sodium hydroxide solution and a saturated sodium chloride solution, and then dried over sodium sulfate. After the solvent was distilled off, the residue was sludged with n-hexane to obtain 3.04 g (93%) of the desired compound.

Workup

  1. temperaturethe suspension was then heated
  2. temperatureunder reflux for 11 hours
  3. distillationNext, thionyl chloride and methanol were distilled off
  4. dissolutionthe residue was dissolved in methylene chloride
  5. washwashed with a 0.5N aqueous sodium hydroxide solution
  6. dry with materiala saturated sodium chloride solution, and then dried over sodium sulfate
  7. distillationAfter the solvent was distilled off

Sources & evidence

ORD record
ord-698c74e68a1f43b1ae73b193c6a981eb
Source dataset
uspto-grants-1998_10
Patent number
US05821258

Reaction notes

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