Trimethyl orthoformate → Methyl 3-chloro-2-methylbenzoate
反応式
[Cl:1][C:2]1[C:3]([CH3:11])=[C:4]([CH:8]=[CH:9][CH:10]=1)[C:5]([OH:7])=[O:6].[CH:12](OC)(OC)OC>CO>[CH3:12][O:6][C:5](=[O:7])[C:4]1[CH:8]=[CH:9][CH:10]=[C:2]([Cl:1])[C:3]=1[CH3:11]参加物
4
反応条件
- 温度
- 60 °C
実験手順
Alternatively, to a suspension of 3-chloro-2-methylbenzoic acid (6.8 g, 40 mmol) in methanol (40 mL) was added trimethyl orthoformate (4.4 mL, 40 mmol). HCl gas was then bubbled through the suspension for 20 minutes. The resulting solution was then heated in a 60° C. oil bath. After stirring at 60° C. for 16 hours, the solution was allowed to cool to ambient temperature and concentrated under reduced pressure to afford a thick yellow paste. The semi-solid was melted under reduced pressure using a heat gun, and then cooled to afford 3-chloro-2-methylbenzoic acid methyl ester (7.1 g, 95% yield) as a yellow crystalline solid: 1H-NMR (400 MHz, CDCl3): δ 7.70 (1H, d, J=7.8 Hz), 7.51 (1H, d, J=7.8 Hz), 7.17 (1H, t, J=7.8 Hz), 3.91 (s, 3H), 2.60 (s, 3H) ppm.