Abstract

The formation of supramolecular aggregates incorporating C(60)fullerenes can be followed and characterized by nuclear magnetic resonance (NMR) measurements. Here, we unravel the particular patterns provided by zinc-porphyrin (ZnP)-bridged dimers, where the aromatic character of each ZnP unit leads to an enhanced shielding region for the closest fullerene atoms, denoting a slight shielding effect for the equatorial atoms. The nature of the stabilization is discussed and compared to a single ZnP-C(60)aggregate and a ZnP-dimer (ZnP2-C-60) model, with a significant contribution from noncovalent pi-pi interactions, allowing us to address the role of bridging chains. The experimental(13)C-NMR spectrum of C(60)in a bridged ZnP dimer shows a single peak owing to the constant tumbling inside the host, which averages the different groups of carbon atoms. The calculations in a static scenario reveal information concerning the local chemical environment underlying the observed shift in relation to isolated C-60. We expect that the current approach can be useful to rationalize and predict the origin of the NMR shift upon the formation of host-guest aggregates involving small and large host species.