Spectroscopic characterization, X-ray molecular structures and cyclic voltammetry study of two (piperazine) cobalt(II) meso-arylporphyin complexes. Application as a catalyst for the degradation of 4-nitrophenol

Two new cobaltous-porphyrin complexes, namely (?-piperazine)-bis[(meso-tetra(para-methoxyphenyl)porphyrinato)]cobalt(II) and (piperazine)[meso-tetra(para-chlorophenyl)porphyrin]cobalt(II) dichloromethane disolvate, with the formulas [{CoII(TMPP)}2(?2-pipz)] (complex 1) [CoII(TClPP)(pipz)]·2CH2Cl2 2), were used efficiently as catalysts in degradation of 4-nitrophenol (4-NP) an aqueous hydrogen peroxide solution. These cobalt(II)-pipz porphyrin complexes characterized by a variety spectroscopic methods including infrared, UV–visible, fluorescence, proton nuclear magnetic resonance, electron paramagnetic resonance (EPR) well mass spectrometry. A cyclic voltammetry investigation was also carried out on these two Co(II) metalloporphyrins. The EPR results indicate that both 1 2 are low-spin (S = 1/2) cobalt(II) complexes. Furthermore, X-ray diffraction crystal structures determined, intermolecular interactions investigated Hirshfeld surface analysis.