Redox Assisted Reversible Aromaticity Transition Between 30π Hückel and 28π Möbius Dication of a Core‐Modified Isophlorinoid.

The electronic properties of a hexaphyrin was fine‐tuned via core‐modification leading to the formation of a Hückel aromatic 30π hexaphyrin which incorporates two pyrrole and four furan rings in the π‐conjugated pathway. This Hückel aromatic hexaphyrin modified its conformation upon two‐electron ring oxidation either with triflic acid or Meerwein salt [Et3O]+[SbCl6]− to yield 28π Möbius aromatic dication species. Reversible aromatic transition was established by spectroscopic techniques and further supported by quantum chemical calculations. [ABSTRACT FROM AUTHOR]