Formaldehyde → HCID 23299998, compound

Participants

Reaction Steps

A mixture of 1-(2-methoxyphenyl)piperazine (2.4 g), 37-40% aqueous formaldehyde solution (0.9 ml) and industrial methylated spirit (30 ml) was stirred at ambient temperature under nitrogen for 18 hours, then a slurry of 5-amino-3-cyclopropyl-1-phenylpyrazole (2.5 g) in industrial methylated spirit (60 ml) was added in one portion. The stirred mixture was heated under reflux for 24 hours then the solvents were removed in vacuo. The residue was purified by reduced pressure column chromatography over silica using a 19:1 mixture of dichloromethane and industrial methylated spirit as eluant. Appropriate fractions were combined and the solvents removed in vacuo. The residue was triturated with acetone and the resulting solid was collected by filtration and dried in vacuo at ambient temperature to give 5-amino-3-cyclopropyl-4-[4-(2-methoxyphenyl)piperazin-1-ylmethyl]-1-phenylpyrazole as a white solid (1.4 g), m.p. 70-74° C.

Provenance & Evidence