反应详情

Diethyl acetylsuccinate (0.3 mL) and a catalytic amount of 4-toluenesulfonic acid monohydrate were added to a solution of 4-mesityl-3-methyl-1H-5-pyrazoleamine (100 mg) of Reference Example 1 in xylene (5 mL). Under heating under reflux, the mixture was stirred for three hours while distilling water off with Dean-Stark. The reaction solution was cooled, water was added thereto. The mixture was extracted twice with ethyl acetate, and washed twice with an aqeous saturated solution of sodium bicarbonate. The organic layer was separated and dried over anhydrous magnesium sulfate. The solvent was evaporated, and the residue was purified by silica gel column chromatography, to give the title compound (200 mg) as a yellow amorphous material.

1. temperatureUnder heating
2. temperatureunder reflux
3. distillationwhile distilling water off with Dean-Stark
4. temperatureThe reaction solution was cooled
5. additionwater was added
6. extractionThe mixture was extracted twice with ethyl acetate
7. washwashed twice with an aqeous saturated solution of sodium bicarbonate
8. customThe organic layer was separated
9. dry with materialdried over anhydrous magnesium sulfate
10. customThe solvent was evaporated
11. customthe residue was purified by silica gel column chromatography