3-(4-chlorophenyl)-4-phenyl-4,5-dihydro-1H-pyrazole → HCID 18407256, compound

Participants

Reaction Steps

Part A: A stirred solution of 3-(4-chlorophenyl)-4,5-dihydro-4-phenyl-1H-pyrazole (5.00 gram, 19.5 mmol) and N-(tert-butoxycarbonyl)aziridine (2.00 gram, 14.0 mmol) in toluene (100 ml) was heated at reflux temperature for 16 hours. After concentration in vacuo the residue was purified by flash chromatography (petroleum ether/diethyl ether=3/1 (v/v)), followed by petroleum ether/diethyl ether=1/1 (v/v)). After concentration in vacuo the remaining oily residue was crystallised from diisopropyl ether to afford 1-[2-((tert-butoxycarbonyl)amino)ethyl]-3-(4-chlorophenyl)-4,5-dihydro-4-phenyl-1H-pyrazole (1.91 gram, 34%). Repeated crystallisations from the mother liquor afforded an additional amount of crystalline 1-[2-((tert-butoxycarbonyl)amino)ethyl]-3-(4-chlorophenyl)-4,5-dihydro-4-phenyl-1H-pyrazole (1.19 gram).

Provenance & Evidence