Ethanol → 1-(2-Fluoro-4-chloro-5-methylsulfonyloxyphenyl)-3,5-dimethylpyrazole

Participants

Reaction Steps

A mixture of 2-fluoro-4-chloro-5-methylsulfonyloxyphenylhydrazine (25.5 g), acetylacetone (10.0 g), ethanol (100 ml) and water (100 ml) was refluxed for 2 hours. After cooling, toluene was added to the reaction mixture to separate layers. The toluene layer as separated was washed with water and then subjected to distillation under a reduced pressure to remove the toluene, yielding the titled compound (29.3 g) as pale yellow crystals. Recrystallization from a mixture of hexane/ethyl acetate gave colorless crystals with melting point 77.5°-79° C.

Provenance & Evidence