Effect of the nature of carboxylate anion on the features of intramolecular hydrogen bonding in [Pd(Hdmpz)4](OOCR)2 (R = Me, Bu t, Ph)

We discovered that reactions of [Pd(OOCMe)2] n and Pd3(μ-OOCMe) with 3,5-dimethylpyrazole (Hdmpz) yield mononuclear complex [Pd(Hdmpz)4](OOCMe)2, in which acetate anions can exchange for pivalate or benzoate anions in reactions with proper acids. The specifics of intramolecular hydrogen bonding in the complexes prepared are discussed as dependent on the nature of the carboxylate anion using X-ray crystallography data.