反应详情

To 14 g (0.1 mole) of 3-amino-5-t-butylpyrazole prepared in Example 1 were added 16.3 g (0.3 mole) of 85% formic acid and 30 ml of toluene, followed by heating under reflux conditions while separating water by distillation. When a calculated amount of water and an excessive amount of formic acid distilled out, the heating was stopped. The reaction mixture was diluted with water and then concentrated as whole, whereby crystals were precipitated. The crystals were collected by filtration, washed with a sodium carbonate aqueous solution and water, and then dried to obtain 8.8 g of 5-t-butyl-3-formylaminopyrazole. This product was recrystallized from hydrous methanol and found to have a melting point of 204° to 206° C.

1. temperatureby heating under reflux conditions
2. customwhile separating water
3. distillationby distillation
4. distillationWhen a calculated amount of water and an excessive amount of formic acid distilled out
5. additionThe reaction mixture was diluted with water
6. concentrationconcentrated as whole, whereby crystals
7. customwere precipitated
8. filtrationThe crystals were collected by filtration
9. washwashed with a sodium carbonate aqueous solution and water
10. customdried