Azulicorrole

Abstract

Acid-catalyzed condensation of pyrrole, 4-trifluoromethylbenzaldehyde, and azulene, followed by DDQ oxidation, has resulted in the isolation of the novel macrocycle azulicorrole, arguably the first example of a carbacorrole aside from N-confused corrole. Despite poor yields (<1%), the free ligand could be structurally characterized and converted to the formal Cu(III) and Au(III) derivatives, of which the Cu(III) complex could also be structurally characterized. Both the free base and the two metal complexes exhibit richly structured UV–vis spectra that extend well into the near-infrared, suggesting potential applications in bioimaging and photodynamic therapy.