Piperidine → 5-(3-bromo-pyridin-5-yl)-1-(2,4-difluoro-phenyl)-3-pentafluoroethyl-4,5-dihydro-1H-pyrazole

Temperature

90 °C

1-(5-Bromo-pyridin-3-yl)-4,4,5,5,5-pentafluoro-pent-1-en-3-one (2.9 g, 8.6 mmol) prepared in Step 3, 2,4-difluorophenylhydrazine hydrochloride (2.4 g, 8.6 mmol), and piperidine (1.7 mL, 17.3 mmol) were added to ethanol (86.4 mL). The reaction mixture was stirred at 90° C. for 18 hours, concentrated under reduced pressure, and then ethyl acetate was added thereto. The mixture was washed with distilled water, dried on anhydrous magnesium sulfate, and then concentrated under reduced pressure to give a yellow liquid residue. The resulting residue was purified by silica gel column chromatography (eluent: ethyl acetate/n-hexane=1/9) to give 2.4 g of the titled compound as a yellow solid.

1. concentrationconcentrated under reduced pressure
2. additionethyl acetate was added
3. washThe mixture was washed with distilled water
4. dry with materialdried on anhydrous magnesium sulfate
5. concentrationconcentrated under reduced pressure
6. customto give a yellow liquid residue
7. customThe resulting residue was purified by silica gel column chromatography (eluent: ethyl acetate/n-hexane=1/9)

ORD record

ord-22398f6c30bb4cb8a5d1dd3bf73f2c5e

Source dataset

uspto-grants-2016_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09376420B2