反应详情

To a mixture of (2,6-dimethyl-phenyl)-acetic acid ethyl ester (13.3 g, 69.2 mmol) in THF (550 mL) and water (224 mL) was added lithium hydroxide monohydrate (23.2 g, 553 mmol). The resulting mixture was stirred vigorously at rt. After 72 h, the mixture was heated to 50° C. for an additional 24 h. The mixture was cooled to rt and concentrated. To the resulting residue was added aqueous 2 N HCl (300 mL) to afford a colorless precipitate. The precipitate was collected by vacuum filtration and further purified by FCC to provide a colorless solid (8.9 g, 78%). MS (ESI): mass calcd. for C10H12O2, 164.1; m/z found, 163.1 [M−H]+. 1H NMR (CDCl3): 7.17-6.90 (m, 3H), 3.72 (s, 2H), 2.33 (s, 6H).

1. temperaturethe mixture was heated to 50° C. for an additional 24 h
2. temperatureThe mixture was cooled to rt
3. concentrationconcentrated
4. additionTo the resulting residue was added aqueous 2 N HCl (300 mL)
5. customto afford a colorless precipitate
6. filtrationThe precipitate was collected by vacuum filtration
7. customfurther purified by FCC