Phenylhydrazine hydrochloride → ethyl 1-phenyl-5-(2,4,5-trifluorophenyl)-1H-pyrazole-4-carboxylate

Participants

Reaction Steps

A solution of ethyl 3-oxo-3-(2,4,5-trifluorophenyl)propanoate (0.326 g, 1.32 mmol) and N,N-dimethyformamide dimethyl acetal in ethanol (5 mL) was heated in a 90° C. oil bath for 3 hours. Upon removal of the volatiles, the residue was dissolved in EtOH (3 mL) and phenylhydrazine hydrochloride salt (191 mg, 1.324 mmol) was added. The mixture was then heated at reflux for 6 hours. The reaction was cooled and diluted with EtOAc and the organic layer was washed with NaHCO3 and brine. The organic phase was dried with Na2SO4, filtered and concentrated to afford the title compound as oil.

Provenance & Evidence