Methanol → Methyl 2-fluoro-3-methylbenzoate
Reaktionsgleichung
[F:1][C:2]1[C:10]([CH3:11])=[CH:9][CH:8]=[CH:7][C:3]=1[C:4]([OH:6])=[O:5].S(Cl)(Cl)=O.[CH3:16]O>>[F:1][C:2]1[C:10]([CH3:11])=[CH:9][CH:8]=[CH:7][C:3]=1[C:4]([O:6][CH3:16])=[O:5]Komponenten
4
Versuchsvorschrift
To a solution of 2-fluoro-3-methylbenzoic acid (12.4 g, 80.2 mmol) in methanol (100 mL) at 0° C. was added thionyl chloride (14 g, 120.3 mmol) dropwise. The reaction mixture was stirred at reflux until complete by TLC (1-2 h). After cooling to room temperature, the mixture was partitioned between sat. NaHCO3 and ethyl acetate. The combined organic layers were dried (Na2SO4), filtered and concentrated to give methyl 2-fluoro-3-methylbenzoate as a yellow oil (13.8 g, 100%): 1H NMR (300 MHz, CDCl3) δ 7.74 (t, J=8.1 Hz, 1H), 7.37 (t, J=7.8 Hz, 1H), 7.08 (t, J=7.5 Hz, 1H), 3.90 (s, 3H), 2.31 (s, 3H).