反应详情

To a solution of 3,5-dibromo-4-pyridinecarboxaldehyde (30.0 g, 113 mmol) in ethanol (1200 mL) at reflux was added 4-fluorophenylhydrazine hydrochloride (20.0 g, 123 mmol) in several portions followed by a solution of sodium acetate (31.0 g, 228 mmol) in water (200 mL). The mixture turned from a deep red to a bright yellow and over time a yellow solid precipitated. After 20 minutes, the mixture was cooled, diluted with water (1000 mL) and the yellow solid was collected by filtration. The solid was washed with water and dried to afford N-[1-(3,5-dibromopyridin-4-yl)-meth-(E)-ylidene]-N′-(4-fluorophenyl)-hydrazine.

1. customprecipitated
2. temperaturethe mixture was cooled
3. additiondiluted with water (1000 mL)
4. filtrationthe yellow solid was collected by filtration
5. washThe solid was washed with water
6. customdried