反应详情

温度

10 °C

Magnesium trifluoromethanesulphonate (11.85 g, 36.73 mmol) was added in one portion to (S)-methyl oxirane-2-carboxylate (15.0 g, 146.93 mmol) and ethanol (10.29 ml, 176.32 mmol) cooled to 10° C. The resulting suspension was stirred at 10° C. for 20 minutes, allowed to warm to ambient temperature and then warmed to 50° C. for 30 hours. The mixture was allowed to cool and diluted with 9:1 DCM:ether (75 mL), filtered through Celite and washed through with 9:1 DCM:ether (3×50 mL) and evaporated. The residue was purified by flash silica chromatography, elution gradient 10 to 50% Et2O in DCM to give methyl (2S)-3-ethoxy-2-hydroxypropanoate (11.6 g, 53%). 1H NMR (400 MHz, CDCl3) δ 1.19 (3H, t), 3.00 (1H, d), 3.47-3.58 (2H, m), 3.72 (2H, d), 3.81 (3H, s), 4.23-4.34 (1H, m).

1. temperatureto warm to ambient temperature
2. temperaturewarmed to 50° C. for 30 hours
3. temperatureto cool
4. filtrationether (75 mL), filtered through Celite
5. washwashed through with 9:1 DCM
6. customether (3×50 mL) and evaporated
7. customThe residue was purified by flash silica chromatography, elution gradient 10 to 50% Et2O in DCM