Thionyl Chloride → 4-(2-Pyridinyl)benzoyl Chloride
Reaktionsgleichung
[N:1]1[CH:6]=[CH:5][CH:4]=[CH:3][C:2]=1[C:7]1[CH:15]=[CH:14][C:10]([C:11](O)=[O:12])=[CH:9][CH:8]=1.S(Cl)([Cl:18])=O>>[N:1]1[CH:6]=[CH:5][CH:4]=[CH:3][C:2]=1[C:7]1[CH:15]=[CH:14][C:10]([C:11]([Cl:18])=[O:12])=[CH:9][CH:8]=1Komponenten
3
Versuchsvorschrift
Thionyl chloride (10 mL) was added to 4-(pyridin-2-yl)benzoic acid (1.8 g, 9 mmol) and the mixture was stirred under reflux overnight. The solvent was evaporated under reduced pressure and the residue was dried in vacuum to give crude 4-(pyridin-2-yl)benzoyl chloride. To a solution of methyl 3-amino-2-hydroxybenzoate (1 g, 6 mmol) and pyridine (480 mg, 6 mmol) in toluene (50 mL) were added the crude 4-(pyridin-2-yl)benzoyl chloride (1.3 g, 6 mmol) portion wise at 0° C. and then stirred at 70° C. for 4 h. The resulting mixture was extracted with ethyl acetate (100 mL×4), the organic phase was washed with water and saturated sodium bicarbonate, dried with anhydrous sodium sulfate and evaporated under reduced pressure to obtain yellow solid of methyl 2-hydroxy-3-(4-(pyridin-2-yl)benzamido)benzoate (1.6 g, yield 76%). LC-MS (ESI) m/z: 349 (M+1)+. (M+1)+.