Hydrazine → 4-Bromo-2-hydrazinylpyridine

Temperature

75 °C

To a solution of 2-fluoro-4-bromopyridine (3.0 g, 17.15 mmol) in pyridine (30 mL) was added anhydrous hydrazine (11 mL, 0.17 mol). The resulting mixture was stirred at 75° C. for 4 h. After cooling to room temperature, the reaction mixture was concentrated to dryness under reduced pressure. To the residue was added water (60 mL), the resulting suspension was stirred at room temperature for 1 h, and then filtered. The collected solid was rinsed with water (2×), then dried in vacuum oven at 50° C. overnight to yield 2.912 g (91%) of the title compound as a light brown solid. The HPLC/MS (method B): retention time=0.60 min, [M+H]+=187.9, 189.9.

1. temperatureAfter cooling to room temperature
2. concentrationthe reaction mixture was concentrated to dryness under reduced pressure
3. additionTo the residue was added water (60 mL)
4. stirringthe resulting suspension was stirred at room temperature for 1 h
5. filtrationfiltered
6. washThe collected solid was rinsed with water (2×)
7. customdried in vacuum oven at 50° C. overnight

ORD record

ord-806b7176ecc74fb79d1c12383b21c810

Source dataset

uspto-grants-2013_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08394823B2