Methanol → 2-Chloro-5-iodo-4-methyl-benzoic acid methyl ester
Reaktionsgleichung
[Cl:1][C:2]1[CH:10]=[C:9]([CH3:11])[C:8]([I:12])=[CH:7][C:3]=1[C:4]([OH:6])=[O:5].S(=O)(=O)(O)O.[CH3:18]O>>[Cl:1][C:2]1[CH:10]=[C:9]([CH3:11])[C:8]([I:12])=[CH:7][C:3]=1[C:4]([O:6][CH3:18])=[O:5]Komponenten
4
Reaktionsbedingungen
- Temperatur
- 60 °C
Versuchsvorschrift
To a solution of 2-chloro-5-iodo-4-methylbenzoic acid (Preparation 49, 2.50 g, 8.43 mmol) in methanol (50 mL) was added concentrated sulfuric acid (1.2 mL) and the reaction was heated at 60° C. for 18 hours. The reaction was cooled, concentrated in vacuo, diluted with water and basified with potassium carbonate until pH=9. The aqueous solution was extracted with EtOAc (3×100 mL), the organic layers combined, washed with water (100 mL), brine (100 mL), dried over magnesium sulphate and concentrated in vacuo to afford the title compound (2.3 g, 88%).