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. (15th November 2021) - Guergueb, Mouhieddinne
Graphical abstract: Synthesis, structural, spectroscopic and electrochemical characterization of two new cobalt(II) piperazine meso -arylporphyrins (Complexes 1 and 2 ). These two compounds were used as efficient absorbents. Abstract: Two new cobaltous-porphyrin complexes, namely (μ-piperazine)-bis[( meso - tetra ( para - methoxyphenyl ) porphyrinato )]cobalt(II) and (piperazine)[ meso -tetra( para -chlorophenyl)porphyrin]cobalt(II) dichloromethane disolvate, with the formulas [{Co II (TMPP)}2 (μ2 -pipz)] (complex 1 ) and [Co II (TClPP)(pipz)]·2CH2 Cl2 (complex 2 ), were used efficiently as catalysts in the degradation of 4-nitrophenol (4-NP) in an aqueous hydrogen peroxide solution. These cobalt(II)-pipz porphyrin complexes were characterized by a variety of spectroscopic methods including infrared, UV–visible, fluorescence, proton nuclear magnetic resonance, electron paramagnetic resonance (EPR) as well as mass spectrometry. A cyclic voltammetry investigation was also carried out on these two Co(II) metalloporphyrins. The EPR results indicate that both complexes 1 and 2 are paramagnetic low-spin (S = 1/2) cobalt(II) porphyrin complexes. Furthermore, the X-ray diffraction crystal structures of 1 and 2 were determined, and the intermolecular interactions were investigated by Hirshfeld surface analysis.