Cyclo[9]pyrrole: Selective Synthesis of [34]Nonaphyrin(0.0.0.0.0.0.0.0.0)

Cyclo­[9]­pyrrole, a ring-expanded porphyrin without meso-bridges and having an odd number of pyrroles, was synthesized via the oxidative coupling of 2,2′:5′,2″-terpyrrole. X-ray crystallography showed a C₂-like symmetry with a large root-mean-square deviation. The optical properties and electronic structures were analyzed using magnetic circular dichroism spectroscopy and time-dependent density functional theory calculations.