Benzaldehyde → 1H-Pyrazole, 3,5-diphenyl-

Participants

Reaction Conditions

Reaction Steps

392 parts (2 mol) of 50% strength sulfuric acid and 1 part (0.0067 mol) of sodium iodide were initially introduced into the stirring flask. 60 parts (0.5 mol) of acetophenone, 53 parts (0.5 mol) of benzaldehyde and 25 parts(0.5 mol) of hydrazine hydrate were simultaneously added dropwise under reflux at 124° C. in the course of 30 minutes. The temperature fellto 112° C. By distilling off water, the temperature was brought to 130° C. and the mixture was stirred at 130° C. for 60 minutes. 120 ml of water were distilled off. The reaction mixture obtainedwas diluted with 250 ml of water and neutralized with 525 parts (3.28 mol) of 25% strength by weight sodium hydroxide solution and filtered. The filter residue was washed with water until sulfate-free and dried. 110.2 parts of 3,5-diphenylpyrazole having a purity of 94.1% (HPLC) were obtained, which corresponds to a yield of 94.3% of theory. M.p.: 194° C.

Provenance & Evidence