Hydrazine → 5-Bromo-2-hydrazinopyridine

To 5-bromo-2-fluoropyridine (3-1) (46 g, 261 mmol) in THF (460 mL) was added hydrazine (41.9 g, 41.0 mL, 1.31 mol). The mixture was heated to reflux and stirred vigorously for 2 h. After cooling, the reaction mixture was diluted with water (200 mL) and extracted with EtOAc (3×500 mL). The combined organic layers were washed with brine, dried over MgSO4, filtered, and concentrated in vacuo. The resulting crude product (3-2) was used in the subsequent step without further purification. LC/MS: m/z (M+H)=187.9.

1. temperatureThe mixture was heated
2. temperatureto reflux
3. temperatureAfter cooling
4. extractionextracted with EtOAc (3×500 mL)
5. washThe combined organic layers were washed with brine
6. dry with materialdried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customThe resulting crude product (3-2) was used in the subsequent step without further purification

ORD record

ord-0e92ab2bc5864884b6b599ccb5e7d462

Source dataset

uspto-grants-2016_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09266881B2