Copper 1,19‐Diaza‐21,24‐Dicarbacorrole: A Corrole Analog with an N‐N Linkage Stabilizes Ground‐State Singlet Organocopper

: A copper complex of a heterocorrole analog with an N-N linkage, 1,19-diaza-21,24-dicarba-dibenzocorrole ( Cu-5 ), was successfully synthesized via oxidative metalation-cyclization of a tetrapyrrolic precursor. The N-N linkage in the skeleton of Cu-5 , which serves as a mediator of π-electron delocalization, features an 18π aromatic system. The electronic structure of Cu-5 is best described as a ground-state singlet species stabilized by the distinct NNCC coordination core. This finding shows how the ligand's design can be used to modulate the Cu 3d x 2 - y 2  orbital energy, thereby making such compounds invaluable for copper-based catalytic applications.