Diels-Alder Reaction of C60 and C70 Fullerenes Confined in a Nanohoop: A Theoretical Study

Chemphyschem. 2025 May 4:e2401026. doi: 10.1002/cphc.202401026. Online ahead of print.

Abstract

The reactivity of the bonds in fullerenes is crucial for their chemical modification of their structures. Recent studies demonstrate that fullerenes can be encapsulated as guest molecule in conjugated [n]cyclodibenzopentalene nanohoop, forming intriguing host-guest systems with potential applications in organic material. In this study, the influence of encapsulating C60 and C70 fullerenes in a [4] cyclodibenzopentalene nanohoop on their bond reactivity is theoretically investigated. The binding energy of the complex of nanohoop and C60 is 2.7 kcal mol-1 higher than that of the nanohoop and C70, highlighting a substantial interaction. However, the differences in bond reactivity between encapsulated and isolated C60 and C70 is relatively small, due to interaction-induced effects from the nanohoop. To understand the origin of these observations, the distortion/interaction analysis was performed . These findings provide insight into how encapsulation affects fullerene reativity and contribute to the broader understanding of weak interactions in supramolecular systems. , The present study on fullerene-nanohoop host-guest system offers new insights into intermolecular weak interactions and enhances our understanding of structural and energetic aspects of molecular recognition and self-assembly in suppramolecular chemistry.

Keywords: Diels–Alder reaction mechanisms; [n]cyclodibenzopentalene nanohoop; distortion‐interaction models; fullerenes.