Pyridine → 3-(4-chlorophenyl)-N-((4-chlorophenyl)sulfonyl)-4-phenyl4,5-dihydro-1H-pyrazole-1-carboxamide

Participants

Reaction Conditions

Reaction Steps

Part A: To a solution of N-((4-chlorophenyl)sulfonyl)carbamic acid methyl ester (CAS: 34543-04-9) (2.99 gram, 12.0 mmol) and pyridine (4 mL) in 1,4-dioxane (20 mL) is added 3-(4-chlorophenyl)-4-phenyl-4,5-dihydro-1H-pyrazole (3.39 gram, 13.2 mmol) and the resulting mixture is stirred for 4 hours at 100° C. After concentration in vacuo the residue is dissolved in dichloromethane, successively washed with water, 1 N HCl and water, dried over anhydrous Na2SO4, filtered and concentrated in vacuo to a volume of 20 mL. Methyl-tert-butyl ether (60 mL) is added and the resulting solution is concentrated to a volume of 20 mL. The formed crystals are collected by filtration and recrystallised from methyl-tert-butyl ether to give 3-(4-chlorophenyl)-N-((4-chlorophenyl)sulfonyl)-4-phenyl-4,5-dihydro-1H-pyrazole-1-carboxamide (4.75 gram, 76% yield) Melting point: 211-214° C.

Provenance & Evidence