Polyfluorinated Pd(II)-3,5-di-tert-butylsalicylaldimenes complexes: synthesis, structure, spectroscopy, redox behaviors and catalytic activity.

A series of new polyfluorinated palladium(II) complexes (7-12) of N-polyfluorophenyl-3,5-di-tert-butylsalicylaldimines (1-6) have been synthesized. They were characterized by analytical, spectroscopic (UV/Vis, IR, (1)H NMR, and ESR), electrochemical methods and their chemical oxidation and hydrogenation catalytic activity were studied. The X-ray crystal structure analysis of bis[N-(3,5-di-tert-butylsalicylidene)-F5Ph]Pd(II) (12) revealed a slightly distorted square-planar trans-PdN2O2 geometry around the palladium center. The UV/Vis and EPR results indicate that chemical oxidation of 7-10 by Ce(IV) in CHCl3 generates relatively stable Pd(II)-phenoxyl radical complexes (g=2.0044-2.0062). The results of chemical and electrochemical oxidation of 1-12, as well as the catalytic activity of 7-10 complexes in the hydrogenation of PhNO2 were presented.