Iron(III) complexes were studied as catalysts in aromatic hydrocarbons oxidation. Toluene was oxidized in yields up to 30%, forming cresols as major products. The reactivity against hydrogen peroxide was followed by UV–vis and ESI–MS. Iron-hydroperoxide intermediate was proposed as the active catalytic species. o-cresol and p-cresol interacts with the intermediate forming a yellow chromophore.