Homogeneous bio-inspired copper-catalyzed oxidation reactions

The controlled oxidation of C–H bonds is one of the most challenging and difficult reactions in organic chemistry. Generally, it requires either stoichiometric amounts of toxic heavy metal salts or very expensive catalysts containing transition metals such as palladium, rhodium or ruthenium. The scientific community used to focus their investigations towards these relatively rare and costly elements while neglecting to look at how Nature performs these types of reactions. Biological systems only employ abundantly available metals like iron, zinc and copper. This review summarizes the background and the state of the art of enzymatic and biomimetic oxidation catalysts involving copper as the active metal center. Recent developments have shown the first very promising results in this incipient field.