反应详情

To a solution of 2-hydroxynicotinic acid (3-067-01) (50 g) in methanol (500 ml) were added conc. sulfuric acid (15 ml) and toluene (100 mL) at room temperature. After the reaction mixture was stirred for 28 h attached Dienstark reflux tube and neutralized with an aqueous potassium carbonate solution, the solvent was evaporated. To the residue were added aqueous saturated ammonium chloride solution and chloroform, and the organic layer was separated, and the aqueous layer was extracted with chloroform. The combined organic layers were dried over anhydrous magnesium sulfate, and evaporated under reduced pressure to give 2-hydroxynicotinic acid methyl ester (3-067-02) (46 g, 84%) as a white solid.

1. temperaturereflux tube
2. customthe solvent was evaporated
3. additionTo the residue were added aqueous saturated ammonium chloride solution and chloroform
4. customthe organic layer was separated
5. extractionthe aqueous layer was extracted with chloroform
6. dry with materialThe combined organic layers were dried over anhydrous magnesium sulfate
7. customevaporated under reduced pressure