Understanding of interactions among molecules is essential to elucidate the binding of pharmaceuticals on receptors, the mechanism of protein folding and self-assembling of organic molecules. While interactions between two aromatic molecules have been examined extensively, little is known about the interactions between two antiaromatic molecules. Theoretical investigations have predicted that antiaromatic molecules should be stabilized when they stack with each other by attractive intermolecular interactions. Here, we report the synthesis of a cyclophane, in which two antiaromatic porphyrin moieties adopt a stacked face-to-face geometry with a distance shorter than the sum of the van der Waals radii of the atoms involved. The aromaticity in this cyclophane has been examined experimentally and theoretically. This cyclophane exhibits three-dimensional spatial current channels between the two subunits, which corroborates the existence of attractive interactions between two antiaromatic π-systems.
Bibliographical noteFunding Information:
This work was supported by JSPS KAKENHI grants JP26102003, JP15K21721, and JP17H01190 (to H.S.) as well as JP17J09817 (to R.N.). This work was also supported by JSPS A3 Foresight Program. H.S. gratefully acknowledges support from the Murata Science Foundation. T.K. is a Cottrell Scholar of the Research Corporation for Science Advancement and acknowledges support from NSF award CHE-1664674. The research at Yonsei University was supported by the Samsung Science and Technology Foundation under project no. SSTF-BA1402-10. H.F. thanks the Norwegian Research Council through the CoE Hylleraas Centre for Quantum Molecular Sciences (Grant nos. 262695 and 231571/F20) for support. This work has received support from the Norwegian Supercomputing Program (NOTUR) through a computer time grant (Grant no. NN4654K) and the supercomputing resources of the Korea Institute of Science and Technology Information.
© 2019, The Author(s).
All Science Journal Classification (ASJC) codes
- Biochemistry, Genetics and Molecular Biology(all)
- Physics and Astronomy(all)