反应详情

To a stirred solution of 0.5 g (2.74 mmol) of D,L 3-(4-hydroxyphenyl) lactic acid hydrate in 10 mL of ethanol was added a catalytic amount of concentrated hydrochloric acid. The mixture was heated at reflux for 2 hours then cooled to room temperature and concentrated under vacuum. The residue was dissolved in 50 mL of ether and washed with saturated aqueous sodium bicarbonate (1×50 mL) and brine (1×50 mL). The organic layer was removed, dried over magnesium sulfate, filtered and evaporated under vacuum to afford 0.54 g (2.57 mmol,94%) of the ethyl ether. 1H NMR (200 MHz,CDCl3): 1.26 (t,7 Hz,3H), 2.86 (dd;7,14 Hz;1H); 3.03 (dd;4,14 Hz; 1H), 4.19 (q,7 Hz,2H), 4.38 (dd;4,7 Hz;1H), 5.60 (br s,1H), 6.66 (d,8 Hz,2H), 7.03 (d,8 Hz,2H).

1. temperatureThe mixture was heated
2. temperatureat reflux for 2 hours
3. concentrationconcentrated under vacuum
4. dissolutionThe residue was dissolved in 50 mL of ether
5. washwashed with saturated aqueous sodium bicarbonate (1×50 mL) and brine (1×50 mL)
6. customThe organic layer was removed
7. dry with materialdried over magnesium sulfate
8. filtrationfiltered
9. customevaporated under vacuum