反应详情

To a solution of 5.79 g of 3,4-dihydroxylphenyl acetic acid ethyl ester dissolved in dry acetone were added 4.48 g of potassium carbonate and 4.15 ml of benzyl bromide. The mixture was heated to reflux until the starting materials were exhausted; and then the solvent was distilled off under reduced pressure. To the residues thus obtained was added 50 ml of water; and the mixture was acidified with concentrated hydrochloric acid and extracted with dichloromethane. The organic layer was dried over magnesium sulfate and evaporated under reduced pressure to obtain residues, which were purified by chromatography to provide 3.80 g (yield 45%) of 3-benzyloxy-4-hydroxyphenylacetic acid ethyl ester, having the characteristics of: NMR(CDCl3, 200 MHz) δ1.24(t, J=7 Hz, 3H, CH3), 3.45(s, 2H, CH2CO), 4.12(q, J=7 Hz, 2H, OCH2), 5.05(s, 2H, CH2Ph), 6.77-7.35(m, 6H, ArH).

1. temperatureThe mixture was heated
2. temperatureto reflux until the starting materials
3. distillationand then the solvent was distilled off under reduced pressure
4. customTo the residues thus obtained
5. extractionextracted with dichloromethane
6. dry with materialThe organic layer was dried over magnesium sulfate
7. customevaporated under reduced pressure
8. customto obtain residues, which
9. customwere purified by chromatography