Benzene ring trimer interactions modulate supramolecular structures

Ring a ring of benzenes: An unsubstituted N-confused metalloporphyrin forms both C₃- and C₁-symmetric trimers in solution, whereas its monophenyl-substituted analogue forms exclusively C₃-symmetric trimers (see picture) owing to significant stabilizing noncovalent interactions between the three phenyl groups, as evaluated both experimentally and theoretically. (Figure Presented).