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

HRID 5370

Reaction equation

HRID 5370 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 mmol) in absolute methanol (20 mL) was treated with 25% sodium methoxide/methanol (2.16 g, 10 mmol), stirred for 30 minutes, and concentrated in vacuo. The solid residue was taken up in anhydrous acetone (30 mL), treated with dimethyl sulfate (1.64 g, 13 mmol), and refluxed for 2 hours. The resultant solution was diluted with water (100 mL), and the precipitate was filtered, washed with water, and dried exhaustively in vacuo to afford 1.75 g (87%) of fine colorless needles. The material was recrystallized from ethyl acetate/hexane; mp 138°-139° C.

Workup

  1. concentrationconcentrated in vacuo
  2. temperaturerefluxed for 2 hours
  3. filtrationthe precipitate was filtered
  4. washwashed with water
  5. customdried exhaustively in vacuo

Sources & evidence

ORD record
ord-5ef4854df60141d78ca949d2c8047a2b
Source dataset
uspto-grants-1993_09
Patent number
US05244907

Linked notes

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