Metalation of C6H6 has been known for a long time as a side reaction occurring in refluxing benzene solutions of Rh-2(CO)(4)(TPP) (TTP = tetraphenylporphyrin). Rather than representing the intrinsic reactivity of this complex, such hydrocarbon activation proceeds via Rh-II(por) and Rh-III(por) derivatives resulting from oxidation of Rh-2(CO)(4)(TPP) with adventitious H2O and/or O-2. This reaction can be extended to other aromatic substrates and represents an efficient synthetic route to certain organometallic Rh-III(TPP) derivatives. [GRAPHICS]