反应详情

To a mixture of methyl 3,4-dihydroxybenzoate (1.0 g, 6.0 mmol), potassium carbonate (3.3 g, 23.8 mmol) and acetonitrile (30 mL) was added 1-bromo-2-(methyloxy)ethane(1.7 mL, 17.9 mmol). The resulting mixture was heated at reflux 18 hour. After cooling to room temperature, the reaction mixture was diluted with ethyl acetate (100 mL), filtered and concentrated. The residue was then diluted with ethyl acetate (100 mL) and washed with 5% sodium hydroxide solution, water and brine (100 mL each), dried over sodium sulfate, filtered and concentrated to give an oily residue which was purified by flash chromatography (silica gel, 30%-50% ethyl acetate-hexane) to provide methyl 3,4-bis{[2-(methyloxy)ethyl]oxy}benzoate (1.1 g, 3.9 mmol, 65% yield). 1H NMR (400 MHz, CDCl3): 7.65-7.63 (d, 1H), 7.55 (s, 1H), 6.90-6.88 (d, 1H), 4.21-4.18 (m, 4H), 3.87 (s, 3H), 3.80-3.77 (m, 4H), 3.45 (s, 6H).

1. temperatureThe resulting mixture was heated
2. temperatureat reflux 18 hour
3. filtrationfiltered
4. concentrationconcentrated
5. additionThe residue was then diluted with ethyl acetate (100 mL)
6. washwashed with 5% sodium hydroxide solution, water and brine (100 mL each)
7. dry with materialdried over sodium sulfate
8. filtrationfiltered
9. concentrationconcentrated
10. customto give an oily residue which
11. customwas purified by flash chromatography (silica gel, 30%-50% ethyl acetate-hexane)