Hydrazine → 2,3,5,6-Tetrafluoro-4-hydrazinylpyridine

Pentafluoropyridine (3.4 g; 20 mmol) was dissolved in dichloromethane (50 mL) and chilled in an ice bath. To the solution was added hydrazine (640 mg; 22 mmol) and it was stirred overnight. The solvent was evaporated, and the residue was dissolved in dichloromethane (50 mL) and washed with a 10% sodium carbonate solution (5 mL). It was dried over magnesium sulfate, and evaporated, to give crude 2,3,5,6-tetrafluoro-pyridin-4-yl-hydrazine. The crude product was then dissolved in ethanol. To the solution was added one drop of acetic acid, and m-tolylaldehyde (1.45 g; 12 mmol) and it was heated at 60° C. overnight. The resulting precipitate was filtered and dried to give N-(3-methyl-benzylidene)-N′-(2,3,5,6-tetrafluoro-pyridin-4-yl)-hydrazine (2.2 g).

1. temperaturechilled in an ice bath
2. customThe solvent was evaporated
3. dissolutionthe residue was dissolved in dichloromethane (50 mL)
4. washwashed with a 10% sodium carbonate solution (5 mL)
5. dry with materialIt was dried over magnesium sulfate
6. customevaporated

ORD record

ord-62eb5c96da2b47728fc7d034d65658dd

Source dataset

uspto-grants-2012_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08173651B2