反应详情

The 3,4-diethyl-2-formylpyrrole (14.1 g, 93.1 mmol) was dissolved in 200 mL of dry ethanol, and ethyl cyanoacetate (20 mL, 137.9 mmol) and diethylamine (20 mL, 193.3 mmol) were added to the solution. The reaction mixture was heated to reflux under an inert atmosphere and stirred under reflux for 2 hours, after which it was cooled to room temperature and then placed in an ice bath. The resulting dark suspension was filtered through a medium filter, and the light brown solids were washed with cold ethanol. The collected filtrates were concentrated under reduced pressure, precipitating more solids. The thick suspension was filtered, and the combined solids were separated and purified to give 2-cyano-3-(3,4-diethyl -1H-pyrrol-2-yl) acrylic acid ethyl ester, a compound of formula 201 in which R1 and R2 are both ethyl.

1. temperatureThe reaction mixture was heated
2. temperatureto reflux under an inert atmosphere
3. temperatureunder reflux for 2 hours
4. customplaced in an ice bath
5. filtrationThe resulting dark suspension was filtered through a medium
6. filtrationfilter
7. washthe light brown solids were washed with cold ethanol
8. concentrationThe collected filtrates were concentrated under reduced pressure
9. customprecipitating more solids
10. filtrationThe thick suspension was filtered
11. customthe combined solids were separated
12. custompurified