反应详情

Concentrated hydrochloric acid (0.1 mL) was added to a solution of 4-mesityl-3-methyl-1H-5-pyrazoleamine (2.5 g, 11.61 mmol) and ethyl 2-cyano-3-ethoxy-2-butenoate (2.13 g, 11.61 mmol) in methanol (30 mL), followed by heating under reflux for 18 hours. The reaction mixture was evaporated as it was. Then, water was added and a 5N aqueous solution of sodium hydroxide was added under ice-cooling, to neutralize. Further, the mixture was extracted with ethyl acetate, and the organic layer was washed with brine, dried over anhydrous magnesium sulfate and evaporated. The residue was purified by silica gel column chromatography (15% ethyl acetate/hexane), to give the title compound (835 mg).

1. temperatureby heating
2. temperatureunder reflux for 18 hours
3. customThe reaction mixture was evaporated as it
4. additionThen, water was added
5. additiona 5N aqueous solution of sodium hydroxide was added under ice-
6. temperaturecooling
7. extractionFurther, the mixture was extracted with ethyl acetate
8. washthe organic layer was washed with brine
9. dry with materialdried over anhydrous magnesium sulfate
10. customevaporated
11. customThe residue was purified by silica gel column chromatography (15% ethyl acetate/hexane)