Designing environmentally friendly homogeneous oxygenation catalysts is still a challenge in chemistry. Natural iron-dependent oxidative enzymes, for example Rieske dioxygenases, such as naphthalene dioxygenase, provide inspiration for researchers.

A biomimetic approach based on Rieske dioxygenase mimics was undertaken by a group of French scientists from Grenoble led by Stéphane Ménage to design a ligand for oxidation catalysts. In the process, they structurally characterized a rare ferrous complex bearing a carboxylate ligand binding through oxygen with an exceptional coordination number of seven. They report the oxidation of challenging trans-aliphatic olefin substrates with H₂O₂ as the oxidant, in which the carboxylate ligand seems to play an important role.

• Iron Coordination Chemistry of N₂Py₂ Ligands Substituted by Carboxylic Moieties and Their Impact on Alkene Oxidation Catalysis
  F. Oddon, E. Girgenti, C. Lebrun, C. Marchi-Delapierre, J. Pécaut, S. Ménage,
  Eur. J. Inorg. Chem. 2011.
  DOI: 10.1002/ejic.201100785