Methanol → HCID 178498433, Verbindung
Reaktionsgleichung
[OH:1][C:2]1[CH:7]=[C:6]([C:8]([OH:10])=[O:9])[CH:5]=[CH:4][N:3]=1.S(Cl)(Cl)=O.[CH3:15]O>>[OH:1][C:2]1[CH:7]=[C:6]([C:8]([O:10][CH3:15])=[O:9])[CH:5]=[CH:4][N:3]=1Komponenten
4
Versuchsvorschrift
To a suspension of 2-hydroxy-4-pyridinecarboxylic acid (Journal of the Chemical Society (1960), 1430-4; 8.45 g, 60.8 mmol) in methanol (200 ml) under nitrogen was added thionyl chloride (7.23 g, 60.8 mmol) dropwise at room temperature. The mixture was then heated under reflux for 4 hrs before being cooled to room temperature. The solvent was removed under vacuum and the residue was dissolved in ethyl acetate. A saturated aqueous solution of sodium bicarbonate was added which formed a precipitate that was removed by filtration. The filtrate was further basified with 2N aqueous sodium hydroxide. The layers were separated and the organic phase was further extracted with ethyl acetate. The combined organic extracts were washed with brine (×2), dried over magnesium sulphate and concentrated under vacuum to give the title compound as a pale brown oil (3.4 g).