Cyclohexane → 4-(Benzenesulfonyl)-1-methyl-3,5-diphenyl-1H-pyrazole

Participants

Reaction Conditions

Reaction Steps

At a temperature of 9° C a solution of m-chloroperbenzoic acid (10.15 g, 85%, 0.05 mole) in dry chloroform (50 ml) is added to a solution of 4-(phenylthio)-1-methyl-3,5-diphenylpyrazole (6.84 g, 0.02 mole) in dry chloroform (50 ml). The reaction mixture is stirred for 3 hours at 9° C and then overnight at room temperature. A heavy precipitate forms. The mixture is treated with 2% aqueous sodium hydroxide and extracted with chloroform. The chloroform layer is separated and stripped in vacuo to give an oil. Trituration of the oil with cyclohexane affords crystals 6.8 g (91%), m.p. 135° C to 141° C. Recrystallization from a mixture of benzene and pentane gave white crystals, m.p. 149° C to 150° C.

Provenance & Evidence