反应详情

温度

130 °C

A mixture of 4-methoxy-phenol (1.10 g, 8.91 mmol) and ethyl-2-butynoate (2.0 g, 17.8 mmol) in tetrahydrofuran (13.7 mL) was treated with 1,8-diazabicyclo[5.4.0]undec-7-ene (1.33 mL, 8.91 mmol). The reaction was then heated at 130° C. for 1.5 h. At this time, the reaction was cooled to 25° C. and was stirred at 25° C. overnight. At this time, the reaction was concentrated in vacuo. The residue was dissolved in dichloromethane (40 mL) and was washed with a 2N aqueous hydrochloric acid solution (1×100 mL), a 1N aqueous sodium hydroxide solution (1×100 mL) and a saturated aqueous sodium chloride solution (1×100 mL). The organics were then dried over sodium sulfate, filtered, rinsed with dichloromethane and concentrated in vacuo. Purification by Analogix flash chromatography (40 g, 10-20% ethyl acetate/hexanes) afforded 3-(4-methoxy-phenoxy)-but-2-enoic acid ethyl ester (0.99 g, 47%) as a clear oil: HR-ES-MS m/z calculated for C13H16O4 [M+H]+ 237.1122, observed 237.1121; 1H NMR (300 MHz, DMSO-d6) δ ppm 1.11 (t, J=7.0 Hz, 3H), 2.41 (s, 3H), 3.76 (s, 3H), 3.98 (q, J=7.0 Hz, 2H), 4.63 (s, 1H), 6.99 (d, J=9.1 Hz, 2H), 7.05 (d, J=9.1 Hz, 2H).

1. temperatureAt this time, the reaction was cooled to 25° C.
2. concentrationAt this time, the reaction was concentrated in vacuo
3. dissolutionThe residue was dissolved in dichloromethane (40 mL)
4. washwas washed with a 2N aqueous hydrochloric acid solution (1×100 mL)
5. dry with materialThe organics were then dried over sodium sulfate
6. filtrationfiltered
7. washrinsed with dichloromethane
8. concentrationconcentrated in vacuo
9. customPurification by Analogix flash chromatography (40 g, 10-20% ethyl acetate/hexanes)