Reaction #939039

Reaction equation

4-Hydroxy-3-nitrobenzoic acid

sulfuric acid

methanol

→

desired compound

Yield 58.0%

Methyl 4-hydroxy-3-nitrobenzoate

Yield 58.0%

Conditions

Workup

1. 1
   Temperaturethe suspension was heated overnight
2. 2
   Temperatureunder reflux
3. 3
   workup.DISTILLATIONThe methanol was distilled off under reduced pressure
4. 4
   workup.DISSOLUTIONThe residue was dissolved in ethyl acetate (40 mL)
5. 5
   Washwashed successively with aqueous sodium hydrogen carbonate (20 mL×2) and saturated aqueous brine (20 mL)
6. 6
   Dryingdried over anhydrous sodium sulfate
7. 7
   workup.DISTILLATIONThe solvent was distilled off under reduced pressure

Procedure

4-Hydroxy-3-nitrobenzoic acid (10.0 g, 54.6 mmol) was suspended in methanol (60 mL). After addition of conc. sulfuric acid (0.1 mL), the suspension was heated overnight under reflux. The methanol was distilled off under reduced pressure. The residue was dissolved in ethyl acetate (40 mL), washed successively with aqueous sodium hydrogen carbonate (20 mL×2) and saturated aqueous brine (20 mL), and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, to give 6.27 g (yield 58%) of the desired compound in the form of a pale brown crystalline product.

Source