Open AccessCopper β-trinitrocorrolates
Author(s) -
Manuela Stefanelli,
Sara Nardis,
Frank R. Fronczek,
Kevin M. Smith,
Roberto Paolesse
Publication year - 2013
Publication title -
journal of porphyrins and phthalocyanines
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.322
H-Index - 64
eISSN - 1099-1409
pISSN - 1088-4246
DOI - 10.1142/s1088424613500120
Subject(s) - corrole , nitration , chemistry , regioselectivity , yield (engineering) , structural isomer , free base , combinatorial chemistry , copper , photochemistry , organic chemistry , salt (chemistry) , materials science , metallurgy , catalysis
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 AgNO 2 /NaNO 2 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 TtBuCorrH 3 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-(NO 2 ) 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-(NO 2 ) 2 corrolate.