Ethanol → 3,4-Diphenylpyrazole

Participants

Reaction Conditions

Reaction Steps

Formyldeoxybenzoin (10 g) was suspended in ethanol (50 ml) and hydrazine hydrate (5 ml) added giving an orange solution which warmed to 40° C. This solution was stirred at room temperature for 3 hours and the solvent evaporated. The resulting oil was taken up in dichloromethane and washed with dilute hydrochloric acid (pH 2) and water, dried over potassium carbonate and evaporated to an orange solid. This was boiled in ether, cooled and filtered giving 3,4-diphenylpyrazole (5.64 g, 57%) as pale yellow crystals, m.p. 155°-6° C.

Provenance & Evidence