Hydrochloric Acid → 5-Bromo-3-chloro-2-hydrazinylpyrazine

Temperature

80 °C

A 250 mL round bottom flask was charged with N′-(5-bromo-3-chloropyrazin-2-yl)-2,2,2-trifluoroacetohydrazide (2.97 g, 9.4 mmol), concentrated HCl (6 mL) and ethanol (60 mL). The resulting mixture was heated at 80° C. for 4 h. The reaction mixture was then allowed to cool to room temperature and neutralized with Na2CO3. It was then diluted with water and extracted with EtOAc (50 mL×3). The combined organic layers were dried over anhydrous Na2SO4 and concentrated in vacuo. The residue was further purified by flash column chromatography on silica gel with 20% EtOAc in petroleum ether, to afford 1.24 g (59%) of the product as a yellow solid.

1. extractionextracted with EtOAc (50 mL×3)
2. dry with materialThe combined organic layers were dried over anhydrous Na2SO4
3. concentrationconcentrated in vacuo
4. customThe residue was further purified by flash column chromatography on silica gel with 20% EtOAc in petroleum ether

ORD record

ord-26cef5b04bfe427998878b029ccc97ee

Source dataset

uspto-grants-2013_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08569300B2