The meso Reactivity of Porphyrins and Related Compounds. I. Nitration

Abstract

The nitration of octaalkylporphyrins under a variety of conditions has been studied. Octaethylporphyrin gave a mononitro derivative under mild conditions, and this is shown to be the meso-substituted compound. Longer reaction times led to the α,β- and α,γ-dinitrooctaethylporphyrins and to a tri-meso-substituted derivative. Mononitro compounds have also been obtained from octamethylporphyrin and mesoporphyrin. Nitration of octaethylchlorin with nitronium tetrafluoroborate gave the γ-nitro and γ,αδ-dinitro derivatives: de-hydrogenation of the former yielded the same nitrooctaethylporphyrin as had been obtained by direct substitution of the porphyrin. © 1965, American Chemical Society. All rights reserved.