Hydrochloric Acid → 1-(2-chloro-phenyl)-5-(3'-methylsulfanyl-biphenyl-4-yl)-3-pentafluoroethyl-4,5-dihydro-1H-pyrazole

Participants

Reaction Conditions

Reaction Steps

4,4,5,5,5-Pentafluoro-1-(3′-methylsulfanyl-biphenyl-4-yl)-pent-1-en-3-one (200.0 mg, 0.54 mmol) prepared in Step 2 of Preparation 2, 2-chlorophenylhydrazine hydrochloride (115.0 mg, 0.64 mmol) and conc. hydrochloric acid (200.0 uL) were added to ethanol (5.0 mL). The reaction mixture was stirred at 100° C. for 18 hours, quenched with a saturated solution of sodium hydrogen carbonate, and then extracted with ethyl acetate three times. The combined extract was washed with brine, 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=1/60) to give 154.0 mg of the titled compound as a yellow liquid.

Provenance & Evidence