2,3-Dihydroxybenzoic Acid → Methyl 2,3-Dihydroxybenzoate
Reaction equation
[C:1](Cl)(=O)C.[OH:5][C:6]1[C:14]([OH:15])=[CH:13][CH:12]=[CH:11][C:7]=1[C:8]([OH:10])=[O:9]>CO>[OH:5][C:6]1[C:14]([OH:15])=[CH:13][CH:12]=[CH:11][C:7]=1[C:8]([O:10][CH3:1])=[O:9]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
Prepare a reaction flask with 300 mL methanol and add 30 mL of acetyl chloride, under argon, in an ice bath. Add 2,3-dihydroxy-benzoic acid (21.70 g, 0.1418 mole) and stir while heating at reflux overnight. Chill in an ice bath and bubble through hydrogen chloride gas for about 10 minutes. Heat the mixture and stir at reflux overnight. Cool to ambient temperature, then concentrate to an off-white solid. Dissolve and separate into diethyl ether and water. Isolating the ether portion and extract twice with 250 mL 5% sodium bicarbonate. Separate, wash with brine and dry over magnesium sulfate. Filter and condense on a rotary evaporator to give the title compound as an off-white solid (21.1 g, 99%). m.p. 79°-81° C.
Workup
- temperaturewhile heating
- temperatureat reflux overnight
- temperatureChill in an ice bath
- custombubble through hydrogen chloride gas for about 10 minutes
- temperatureHeat the mixture
- temperatureat reflux overnight
- concentrationconcentrate to an off-white solid
- dissolutionDissolve
- customseparate into diethyl ether and water
- customIsolating the ether portion
- extractionextract twice with 250 mL 5% sodium bicarbonate
- customSeparate
- washwash with brine
- dry with materialdry over magnesium sulfate
- filtrationFilter
- customcondense
- customon a rotary evaporator
Sources & evidence
- ORD record
- ord-0d07fc4da25e472b9d113fdc89bd7347
- Source dataset
- uspto-grants-1999_12
- Patent number
- US06004959
Reaction notes
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