反应详情

A mixture of 2-isopropylpyrazolo[1,5-a]pyridine-3-carbaldehyde (0.5 g, 1 equivalent), semicarbazide hydrochloride (0.35 g, 1.2 equivalents), and triethylamine (0.4 mL, 1.1 equivalent) in 5 mL of methanol was reflux for 30 minutes. The solution was concentrated and the crude solids produced were extracted with THF, and the mixture was filtered through a 1 inch thick layer of sodium sulfate on top of a thin pad of silica gel to remove the ammonium salt. The filtrate was concentrated and the solid deposited was recrystallized from THF and hexanes to give (E)-2-((2-isopropylpyrazolo[1,5-a]pyridin-3-yl)methylene)hydrazinecarboxamide (0.46 g, 70% yield) as a yellow solid. Compound 1074.

1. temperaturewas reflux for 30 minutes
2. concentrationThe solution was concentrated
3. customthe crude solids produced
4. extractionwere extracted with THF
5. filtrationthe mixture was filtered through a 1 inch thick layer of sodium sulfate on top of a thin pad of silica gel
6. customto remove the ammonium salt
7. concentrationThe filtrate was concentrated
8. customthe solid deposited was recrystallized from THF and hexanes