Synthesis, spectral properties and stability towards protolytic dissociation of the palladium(II) complexes with dipyrrolylmethene and its bis-derivatives
摘要:
Palladium(II) complexes with alkylated dipyrrolylmethene (Hdpm) and its bis-derivative, biladienea, c (H(2)bd), of the composition [Pd(dpm)(2)] and [Pd(bd)] were synthesized and were characterized by IR, UVVIS, and NMR spectroscopy. It was shown that the nature of the solvent has almost no effect on the spectral characteristics of the complexes due to the square-planar configuration of the coordination nodes in them and, respectively, the impossibility of further coordination. From the results of the kinetic study of the complexes stability to the action of acids in the C6H6-CCl3COOH mixtures it was concluded that the Pd(II) complexes are much more stable compared to the other d-metal dipyrrolylmethenates. Kinetic manifestation of polychelate effect was observed consisting in a sharp decrease in the dissociation rate of the palladium(II) complex with biladiene as compared to that with dipyrrolylmetene.