Effect of substituent, metal and pH on the peroxidase activity of metal complexes with Schiff-base ligands

COLAGIOIA, R; PALOPOLI, C.; SIGNORELLA, S. R.; FERREYRA, J.

Fortaleza

Congreso; VI Latin American Meeting on Biological Inorganic Chemistry; 2018

Sociedad Brasilera de Química - División Inorgánica

Lignin is the largest renewable raw material containing aromatic fragments. However, no processes have been developed to obtain aromatic products from this natural source. Metal complexes of Schiff-base ligands show a rich redox chemistry modulated by ligand substituents and reaction conditions [1,2] and can afford high-valent metal-oxo complexes able to act as O-atom transfer agents with a variety of substrates. This kind of complexes can mimic ligninolytic enzymes that employ H2O2 for lignin degradation [2].In this work, complexes of Mn(III), Co(II) and Cu(II) with Schiff-base ligands derived from 1,3-bis(salicylidenamino)propane (X-salpn, X = aromatic substituent) were used as peroxidase mimics for the oxidation of lignin models using H2O2 as terminal oxidant, at pH 7 and 9 and room temperature.