Homochiral and Heterochiral Self‐Sorting Assemblies of Antiaromatic Ni(II) Norcorrole Dimers

Abstract

AbstractRecently, π–π stacked antiaromatic π‐systems have received considerable attention because they can exhibit stacked‐ring aromaticity due to substantial intermolecular orbital interactions. Here, we report three antiaromatic norcorrole dimers that self‐assemble to form supramolecular architectures through chiral self‐sorting. A 2,2’‐linked norcorrole dimer with 3,5‐di‐tert‐butylphenyl groups forms a π‐stacked dimer both in solid and solution states via homochiral self‐sorting. Its association constant in solution is (3.6±1.7)×105 M−1 at 20 °C. In the solid state, 3,3’‐linked norcorrole dimers with 3,5‐di‐tert‐butylphenyl and phenyl groups afford macrocyclic and helical supramolecular assemblies via heterochiral and homochiral self‐sorting, respectively. Notably, the subtle modification in the substituent resulted in a complete change in the structure of the aggregates and the chiral self‐sorting mode. The present findings demonstrate that structural manipulation in antiaromatic monomer units leads to the formation of various supramolecular assemblies on the basis of the attractive interactions between antiaromatic π‐systems.