New cationic palladium(II) compounds with several bidentate nitrogen-donor ligands: Synthesis, spectroscopic analyses and X-ray crystal structure

A series of PdN4core complexes has been synthesised. Reaction of [PdCl2(CH3CN)2] with N-alkylaminopyrazole (NN′) ligands, 1-[2-(ethylamino)ethyl]-3,5-dimethylpyrazole (deae), 1-[2-(ipropylamino)ethyl]-3,5-dimethylpyrazole (deai), and 1-[2-(tbutylamino)ethyl]-3,5-dimethylpyrazole (deat) in the presence of AgBF4 led to [Pd(NN′)2](BF4)2. These palladium(II) compounds were characterised by elemental analyses, conductivity measurements, IR, 1H and 13C{1H} NMR spectroscopies. The NMR studies of the complexes prove the rigid conformation of the ligands when they are complexed. The X-ray analyses of one representative complex, [Pd(deat)2](BF4)2, is reported. The crystal structure consists of discrete centrosymmetric cations involving a coordinated Pd(Npz)2(Namino)2core   with planar geometry and BF4- anions.

Graphical abstractReaction of [PdCl2(CH3CN)2] with N-alkylaminopyrazole (NN′) ligands, 1-[2-(ethylamino)ethyl]-3,5-dimethylpyrazole (deae), 1-[2-(ipropylamino)ethyl]-3,5-dimethylpyrazole (deai), and 1-[2-(tbutylamino)ethyl]-3,5-dimethylpyrazole (deat) in presence of AgBF4 led to [Pd(NN′)2](BF4)2. The X-ray analyses of one representative complex, [Pd(deat)2](BF4)2, is reported. The crystal structure consists of discrete centrosymmetric cations involving a coordinated Pd(Npz)2(Namino)2core   with planar geometry and BF4- anions. These palladium(II) complexes were characterised by elemental analyses, conductivity measurements, IR, 1H and 13C{1H} NMR spectroscopies. The NMR studies of the complexes prove the rigid conformation of the ligands when they are complexed.Figure optionsDownload full-size imageDownload as PowerPoint slide