Copper(II) complexes based on isopropyl ester derivatives of bis(pyrazol-1-yl)acetate ligands with catalytic potency in organic macro(molecules) synthesis

In this work, bis(pyrazol-1-yl)acetic acid (HC(pz)2COOH) and bis(3,5-dimethyl-pyrazol-1-yl)acetic acid (HC(3,5-Me2pz)2COOH) were converted into the isopropyl ester derivatives 1 (L1iPr) and 2 (L2iPr), respectively, and used for the preparation of the Cu(II) complexes 3-6 implementing an existing method for a new field of application. All synthesized compounds were characterized by spectroscopic and physicochemical methods. The crystal structure of the ligand L2iPr was determined by X-ray diffraction analysis. The novel synthesized Cu(II) complexes were applied in the synthesis of oxidized protected olefins via Kharasch-Sosnovsky reaction, using electron rich and electron poor alkenes in order to synthesize allyl benzoates and poly(methyl methacrylate), respectively. Our findings suggest that the developed copper(II) complexes can be promising catalysts for further organic modifications.