3-Aryl-5-(2-pyridyl)pyrazoles and related compounds are easily accessible via the reaction of the appropriate 1,3-diketone with hydrazine hydrate. The central pyrazole rings show a far-reaching equalization of the bond lengths. In the crystalline state dimeric and strand-like structures are observed due to the formation of intermolecular N–H···N hydrogen bridges between the pyrazole N–H functionality