Doubly <i>N</i>‑Methylated Porphyrinoids

Chirality-induced aromatic π-electronic
macrocycles, porphyrin
and corroles, were synthesized through doubly inner N-methylation through multistep and one-pot reactions, respectively.
The exact structures of doubly N-methylated porphyrin
and corroles were revealed by single-crystal synchrotron X-ray analysis,
exhibiting two N-methyl groups located on neighboring
pyrrole rings in up/down conformations. These doubly inner N-substitutions
of the π-electronic macrocycles induced distorted geometries,
resulting in chiroptical properties after optical resolutions.