Porphyrins bearing corannulene pincers: outstanding fullerene receptors

Abstract

Herein, we study new fullerene receptors which are constructed employing porphyrins, corannulene pincers and metallic centers. Theoretical calculations indicated that if porphyrin and corannulene pincers are merged, the strongest hosts for fullerenes can be built. We found that there is a linear increase of the interaction energy with respect to the number of pincers. The linear trend is broken when the pincers interact amongst themselves. The strongest host–C₆₀ interaction was observed for the porphyrin which has 4 corannulene pincers and Ir or Rh centers, which exhibited interaction energies significantly larger than the one computed for the dimeric porphyrins. In addition, we report that some of the porphyrin receptors can host two fullerene molecules very efficiently, given that the host can be deformed without increasing its energy too much. Finally, we observed a good sensitivity of our hosts towards C₇₀ with respect to C₆₀. Synthetic routes of the hosts designed are discussed.