Complexes of Some d and f Elements with New 4-Acylpyrazol-5-ones: Synthesis and Study

Complexes of 1-phenyl-3-methyl-4-thenoylpyrazol-5-one and of 1-phenyl-3-methyl-4-furancarbonylpyrazol-5-one, which was synthesized for the first time, with copper, rhodium, lanthanum, and europium were studied. The substances obtained were studied using elemental analysis and IR spectroscopy, while the rhodium derivatives were additionally studied using the ¹H NMR method. The thermal stability of the copper derivatives was studied upon heating in a vacuum. The presence of additional heteroatoms in acylpyrazolone had virtually no effect on the structure and composition of the complexes formed. These ligands were shown to coordinate atoms of d and f metals through oxygen atoms similarly to other -diketones, whereas the remaining heteroatoms only participated in the formation of a hydrogen bonding system with additional ligands or coordinated solvent molecules.