Water → 1-(2,4-Difluorophenyl)-2-(1H-pyrazol-1-yl)ethanone

Participants

Reaction Steps

A mixture of 1H-pyrazole (1.3 mol) in 4-methyl-2-pentanone (500 ml) was stirred and refluxed. 1-(2,4-difluorophenyl)-2-chloroethanone (0.26 mol) dissolved in 4-methyl-2-pentanone (500 ml) was added dropwise and the mixture was stirred and refluxed for 3 h. The mixture was cooled, poured into water and separated. The organic layer was evaporated. The residue was stirred up in HCl/water, filtered off and washed with water. The precipitate was stirred up in hexane, filtered off and dried in vacuo at 45° C., yielding 45 g (78%) of 1-(2,4-difluorophenyl)-2-(1H-pyrazol-1-yl)ethanone; mp. 76.4° C. (interm. 12).

Provenance & Evidence