Peculiarities of the Catalytic Activity of Copper Compound Containing Ligand with Paramagnetic Centers

Resumo

Experimental data have been obtained to evaluate the catalytic activity of copper chelate Cu(NO•)₂ with the paramagnetic ligand in the degradation reactions of hydroperoxide and diacyl peroxide in the aprotic solvent chlorobenzene or in ethyl alcohol, which is capable of forming intermolecular hydrogen bonds. The presence of paramagnetic centers in the ligand have an insignificant effect on the catalytic activity of the copper chelate in the reaction with tetralyl hydroperoxide and benzoyl peroxide in chlorobenzene as compared to another compound CuL₂, which have no paramagnetic centers in the ligand. The catalytic activity of Cu(NO^•)₂ has been found to increase during the reaction with benzoyl peroxide in chlorobenzene, in contrast to CuL₂, which is completely deactivated in this reaction. The EPR spectra of the chelate Cu(NO^•)₂ exhibit a signal due to the nitroxide radical alone. The signal of the central Cu atom is not observed; i.e., there is the case of EPR-undetectable copper in this coordination compound.