反应详情

To a 250 mL round bottom flask fitted with a reflux condenser and a nitrogen inlet tube was added 20.0 g (121.8 mmol) 4-hydroxycinnamic acid, 100 mL (246.9 mmol) methanol, and 5.0 g (50.0 mmol) concentrated sulfuric acid. The reaction vessel was heated at 75°-80° C. overnight. After cooling to room temperature, the resulting solution was diluted with 150 mL distilled water, and cooled to 0° C. The resulting precipitate was filtered, washed with sat. NaHCO3 solution, and recrystallized from EtOH/water to afford 16.8 g (77%) methyl 4-hydroxycinnamate which was used without further purification: mp.=139°-140° C.; 1H NMR (CD3SOCD3, 300 MHz) δ 3.42 (broad s, 1H), 3.70 (s, 3H), 6.40 (d, J=16.0 Hz, 1H), 6.81 (d, J=8.4 Hz, 2H), 7.55 (d, J=8.4 Hz, 2H), 7.58 (d, J=16.0 Hz, 1H).

1. customTo a 250 mL round bottom flask fitted with a reflux condenser and a nitrogen inlet tube
2. temperatureThe reaction vessel was heated at 75°-80° C. overnight
3. additionthe resulting solution was diluted with 150 mL
4. distillationdistilled water
5. temperaturecooled to 0° C
6. filtrationThe resulting precipitate was filtered
7. washwashed with sat. NaHCO3 solution
8. customrecrystallized from EtOH/water