Synthesis, X-structure and solvent induced electronic states tuning of meso-tris(4-nitrophenyl)corrolato-copper complex

Copper(II) ion insertion into the coordination core of meso-tris(p-nitrophenyl)corrole (1), in air showed the formation of meso-tris(p-nitrophenyl)corrolatoCu(III) (2), with the generation of superoxide radical as the side product of the reaction. Single-crystal X-ray diffraction analysis revealed that 2 exhibits weak π–π stacking interaction. Among the two electronic states, diamagnetic Cu(III)–corrole3− exits in DCM solution and in contrast is paramagnetic Cu(II)–corrole2− cationic radical in DMF solution. This difference in electronic behavior in solution is due to the small energy gap between HOMO and LUMO that is readily influenced by solvent interaction.