反应详情

温度

130 °C

[3-(3,5-Dimethyl-4-isoxazolyl)-4-(methyloxy)phenyl]amine (for a preparation see Intermediate 2) (39 g, 179 mmol) was dissolved in diethyl [(ethyloxy)methylidene]propanedioate (38.6 g, 179 mmol) and heated to 130° C., giving a steady effervescence as ethanol boiled off. The solution was heated for 1 h, then cooled to room temperature and evaporated in vacuo to give a brown oil. The product was dissolved in DCM (100 ml) and loaded onto a 750 g silica column, then eluted with 0-100% EtOAc/cyclohexane to give diethyl({[3-(3,5-dimethyl-4-isoxazolyl)-4-(methyloxy)phenyl]amino}methylidene)propanedioate (59.5 g, 153 mmol, 86% yield) as pale yellow crystalline solid. LCMS (formate) Rt 1.15 min, MH+ 389.

1. temperatureThe solution was heated for 1 h
2. temperaturecooled to room temperature
3. customevaporated in vacuo
4. customto give a brown oil
5. washeluted with 0-100% EtOAc/cyclohexane