反应详情

A solution of methyl 2-(4-fluoro-3-methoxyphenyl)-2-methylpropanoate (146 g) in MeOH (2 L) and 25% NaOH in H2O (590 mL) was heated at reflux for 5 h. The reaction mixture was then allowed to cool to room temperature and concentrated at reduced pressure. The residue was dissolved in H2O (2 L) and washed with ether (500 mL). The aqueous layer was acidified cautiously with conc HCl to pH 2. The resulting mixture was extracted with DCM (3 L), and combined extracts were dried over MgSO4, and concentrated at reduced pressure to give 2-(4-fluoro-3-methoxyphenyl)-2-methylpropanoic acid (95 g, 84% over 2 steps). 1H NMR (400 MHz, CDCl3): δ 7.06-7.00 (m, 2H), 6.93 (m, 1H), 3.90 (s, 3H), 3.86 (s, 2H), 1.60 (s, 6H).

1. temperatureat reflux for 5 h
2. concentrationconcentrated at reduced pressure
3. dissolutionThe residue was dissolved in H2O (2 L)
4. washwashed with ether (500 mL)
5. extractionThe resulting mixture was extracted with DCM (3 L)
6. dry with materialwere dried over MgSO4
7. concentrationconcentrated at reduced pressure