Catalytic study of new complexes based on pyrazole ligands

The efficiency and selectivity of copper-containing metalloenzymes in the oxidation of catechol to o-quinone by atmospheric oxygen has led coordination chemists to investigate the structural and catalytic properties of these enzymes. The present work focuses on the synthesis of new ligands and complexes based on pyrazole structures. These compounds have been studied for their catalytic properties in catalyzing the oxidation reactions of catechols and phenols to o-quinones and of 2-aminophenol to 2-aminophenoxazinone.The aim of these studies is to find better models for the development of the catalytic activity of enzymes (catecholase, tyrosinase and phenoxazinone synthase), by synthesizing new complexes and others prepared in situ by pyrazole derivatives in association with transition metals. Some of these complexes were found to exhibit excellent catalytic activity for these reactions.