反应详情

A mixture of methyl 3-ethoxy-4-methoxybenzoate (4.42 g), methanol (160 mL) and IN-sodium hydroxide solution (40 mL) was heated for 2 hours under reflux. The reaction mixture was acidified with 1N-hydrochloric acid to pH 4, and the organic solvent was removed by evaporation. The aqueous layer was diluted with water and extracted with ethyl acetate. The extract was washed with brine, dried over magnesium sulfate and evaporated in vacuo. The residue was triturated with hexane to give 3-ethoxy-4-methoxybenzoic acid as colorless powders (3.76 g). NMR (CDCl3, δ): 1.50 (3H, t, J=7 Hz), 3.95 (3H, s), 4.17 (2H, q, J=7 Hz), 6.92 (1H, d, J=8 Hz), 7.60 (1H, d, J=4 Hz), 7.76 (1H, dd, J=4, 8 Hz); Mass m/z: 195(M+).

1. temperatureunder reflux
2. customthe organic solvent was removed by evaporation
3. additionThe aqueous layer was diluted with water
4. extractionextracted with ethyl acetate
5. washThe extract was washed with brine
6. dry with materialdried over magnesium sulfate
7. customevaporated in vacuo
8. customThe residue was triturated with hexane