The catalytic cycle of cytochrome P-450 is believed to involve reductive activation of dioxygen at the heme center andsubsequent peroxy bond clcavagc to give a ferry ion spccicsas the active oxygen transfer agent.1.2 Support for an iron-oxo species such as 1 is derived from the fact that a number of single oxygen donors, hydroperoxides, peroxy acids, and iodosylbenzcne, effect oxygen transfer in a manner similar inmany rcspccts to the fully reconstituted enzyme system.35 as part of our program to evaluate simple iron catalysts as oxygentransfer agents,6.7 we have found that chloro-α,β,γ,δ-tetra-phenylporphinatoiron(III) (2) and chlorodimethylferripro-toporphyrin IX (3) catalyze the hydroxylation and epoxidationof hydrocarbons with lodosvlbcnzene as an oxygen source.© 1979, American Chemical Society. All rights reserved.