The β-nitration reaction carried out on the corrole macrocycle has been shown to be extremely regioselective, although the reduced symmetry of the macrocycle could potentially lead to a huge number of possible regioisomers. We recently reported that the careful use of AgNO2/NaNO2 as a nitrating system enabled the achievement in good yields of mono- and dinitro-derivatives on both corrole free base and its copper complex, proving to be an efficient and cost-effective method. In this work, we present a detailed study of the scope of this method using TtBuCorrH3 as a model corrole. A further increase of the oxidant pushes the nitration up to the functionalization of three β-pyrrolic positions, although concomitant decomposition of the macrocycle is also observed. The application of the proven nitration method with a five-fold excess of both silver and sodium nitrites with respect to corrole, afforded the 2,3,17-(NO2)3- TtBuPCorrCu as the main product, in 25% yield, together with traces of another compound identified by X-ray crystallographic analysis as the 3,8,17-(NO 2)3-TtBuPCorrCu isomer. In light of these recent results, we also reinvestigated the characterization of the nitration products obtained from bis-substitution reactions, allowing among others the identification of the copper 3,8-(NO2)2 corrolate. © 2013 World Scientific Publishing Company.
Publication Source (Journal or Book title)
Journal of Porphyrins and Phthalocyanines
Stefanelli, M., Nardis, S., Fronczek, F., Smith, K., & Paolesse, R. (2013). Copper β-trinitrocorrolates. Journal of Porphyrins and Phthalocyanines, 17 (6-7), 440-446. https://doi.org/10.1142/S1088424613500120