Influence of Ligands Basicity on Complexation Kinetics of 5,10,15,20-Tetra(trifluoromethyl)porphyn and 5,10,15,20-Tetra(iso-Butyl)porphyn With Copper Acetate

Abstract

Spectrophotometric studies of base and complexation properties of 5,10,15,20-tetra(trifluoromethyl)porphine and 5,10,15,20-tetra(iso-butyl)porphine were carried out in systems acetonitrile – HClO4 and CH3COOH – Cu(ОАc)2. It was found that under ligands titration with perchloric acid in acetonitrile the consecutive protonating of nitrogen atoms of pyrrolic rings occurs with formation of mono – and dicationic forms. Electron absorption spectra may be obtained for these cationic forms. Total basicity constants and concentration intervals of existence of ligands ionized forms in acetonitrile were determined. Kinetic parameters of copper(II) complex formation was measured. The influence of nature of meso-position substituents of porphyrin macrocycle on reactivity of tetrapyrrolic macrocycle was dicussed.