Dimethyl Sulfate → Methyl 4-amino-5-chloro-2-hydroxybenzoate

HRID 2254607Notes

Reaction equation

HRID 2254607 reaction equation
[NH2:1][C:2]1[C:10]([Cl:11])=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[C:4]([OH:12])[CH:3]=1.C[O-].[Na+].CO.S(OC)(O[CH3:22])(=O)=O>CO.O>[NH2:1][C:2]1[C:10]([Cl:11])=[CH:9][C:5]([C:6]([O:8][CH3:22])=[O:7])=[C:4]([OH:12])[CH:3]=1

Participants

6

Reactant 3

HCID 6497Dimethyl SulfateHCID 148832224-Amino-5-chloro-2-hydroxybenzoic acidHCID 23694274Sodium methanolate methanol

Product 1

HCID 14883223Methyl 4-amino-5-chloro-2-hydroxybenzoateYield 87%

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 962WaterSolvent

Procedure

A solution of 4-amino-5-chloro-2-hydroxybenzoic acid (1.88 g, 10 mmoles) in absolute methanol (20 ml) was treated with 25% sodium methoxide/methanol (2.16 g, 10 mmoles), stirred for 30 minutes, and concentrated in vacuo. The solid residue was dissolved in anhydrous acetone (30 ml), treated with dimethyl sulfate (1.64 g, 13 mmoles), and refluxed for 2 hours. The resultant solution was diluted with water (100 ml), and the precipitate was filtered, washed with water, and dried in vacuo to yield 1.75 g (87%) of fine colorless needles. The product was recrystallized from ethyl acetate/hexane, mp 138°-139° C.

Workup

  1. concentrationconcentrated in vacuo
  2. dissolutionThe solid residue was dissolved in anhydrous acetone (30 ml)
  3. temperaturerefluxed for 2 hours
  4. filtrationthe precipitate was filtered
  5. washwashed with water
  6. customdried in vacuo

Sources & evidence

ORD record
ord-c12ae305e1a0434ba2eca9e065d6c3a3
Source dataset
uspto-grants-1993_08
Patent number
US05236931

Reaction notes

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