Acetic Acid → 1-Methyl-4-piperidyl (5-p-chlorophenyl-1-phenylpyrazol-4-yl)-acetate

Participants

Reaction Steps

35.1 g of 1-methyl-4-piperidyl 3-p-chlorobenzoyl-4-dimethylamino-3-butenoate [obtainable by esterification of 3-p-chlorobenzoyl-propionic acid with 1-methyl-piperidin-4-ol to produce 1-methyl-4-piperidyl 3-p-chloro-benzoylpropionate and subsequent reaction of the latter with dimethylformamide dimethyl acetal in the presence of acetic acid at 120°] and 12 g of phenylhydrazine are warmed for 4 hours at 100°. The reaction mixture is subjected to the customary working up (benzene/water) and 1-methyl-4-piperidyl 5-p-chlorophenyl-1-phenyl-pyrazol-4-yl-acetate is obtained; m.p. 90°-93°. Hydrochloride, m.p. 234°-235°.

Provenance & Evidence