In the presence of imidazole, iron-and manganese-porphyrins catalyse the epoxidation of alkenes by alkyl hydroperoxides

Abstract
In the presence of imidazole, Mn(TPP)(Cl)and Fe(TPP)(Cl)(TPP = tetraphenylporphyrin)catalyse the epoxidation of styrene, cyclohexene, 2-methylhept-2-ene, and stilbene by cumyl hydroperoxide; in the case of Mn(TPP)(Cl), a transient species, characterized by a Soret peak at 426 nm similar to that of a previously described high-valent Mn-oxo species, is detected at –37 °C.