Calix[6]arene-based models for mono-copper enzymes: a promising supramolecular system for oxidation catalysis

A novel supramolecular system that mimics the mono-copper site of enzymes i s described. It is based on a calix[6]arene presenting either three pyridin e (Py) or three imidazole (Im) groups that coordinate the copper renter. Wh ereas Cu(I) is tetrahedral, Cu(II) is 5-coordinate. In both cases however, the Cu complexes possess a labile site located inside the calixarene cavity . A comparative study of the Py- and Im-based systems is presented in Germs of chemical behaviour, electrochemistry and reactivity in the presence of hydrogen peroxide. Hence, the Py-based Cu(II) complex appears as the most i nteresting catalyst for the oxidation of aromatics and alcohols (C) 2000 Ac ademie des sciences / Editions scientifiques et medicales Elsevier SAS.