反应详情

温度

85 °C

To a solution of (2-isopropyl-4-methoxy-5-methyl-phenoxy)-acetic acid ethyl ester (4.42 g, 16.6 mmol) in anhydrous 1,2-dimethoxy ethane (60 ml) was added sodium hydride (60% in mineral oil, 3.5 g, 87.5 mmol) at room temperature. After 5 minutes of stirring, ethyl formate (40 ml, 495 mmol) was added. The mixture was heated at 85° C. for 7 hours. After cooling to room temperature, iodomethane was added and stirring was continued overnight. Solvent was concentrated under reduced pressure and the residue was partitioned between ethyl acetate and water. The organic phase was washed with brine and dried over anhydrous sodium sulfate. After removal of drying agent, the organic solution was concentrated under reduced pressure. The residue was purified with silica gel chromatography (10% to 30% ethyl acetate in hexane) to yield 2-(2-isopropyl-4-methoxy-5-methyl-phenoxy)-3-methoxy-acrylic acid ethyl ester as a pale yellow oil (1.19 g, 23%).

1. temperatureAfter cooling to room temperature
2. stirringstirring
3. waitwas continued overnight
4. concentrationSolvent was concentrated under reduced pressure
5. customthe residue was partitioned between ethyl acetate and water
6. washThe organic phase was washed with brine
7. dry with materialdried over anhydrous sodium sulfate
8. customAfter removal
9. customof drying agent
10. concentrationthe organic solution was concentrated under reduced pressure
11. customThe residue was purified with silica gel chromatography (10% to 30% ethyl acetate in hexane)