Palladium(II) Complexes Based on N,S-Donor Ligands: Synthesis and Molecular Structures

Phenyl(chloro)dithioformate is treated with pyrazole derivatives and phenyl(Pz-1-carbodithioate) ligands (Pz = pyrazole (1), 3-methylpyrazole (2), and 3,5-dimethylpyrazole (3)) are obtained. These ligands are treated with PdCl2 in acetonitrile and complexes of the general formula Pd(L)Cl2 form in an essentially quantitative yield. The ligands are found to be N,S-bidentate linkers, and 5-membered palladacycles are obtained. Precursors 1–3 are oily materials and characterized by 1H and 13C NMR spectroscopy. Due to a partial solubility of Pd complexes, the complete set of NMR data cannot be collected. The structural elucidation is also accompanied by elemental and mass spectrometric analyses. Solid-state structures of complexes 5 and 6 are determined by X-ray diffraction. The data obtained for complexes 5 and 6 are also calculated by DFT using the TURBOMOLE program package. Experimental and calculated data sets are found to be in close agreement with each other.