The oxidation of cyclohexane with molecular oxygen (1 atm) in the presence of isobutyraldehyde catalyzed by nanostructured iron and cobalt oxides and iron supported on titania has been studied. It was found that highly dispersed transition metals oxide is more effective for oxidation than the corresponding zero valent powders. In the titania supported catalysts iron exists as iron (III) oxide segregated to the surface layers and stabilized by titania. This form is the most active in the cyclohexane oxidation under mild conditions.