Molecular Basis for the Recognition of Higher Fullerenes into Ureidopyrimidinone-Cyclotriveratrylene Self-Assembled Capsules
<p> Fullerenes C<sub>60</sub>, C<sub>70</sub>, and C<sub>84</sub> may be readily encaged within a hydrogen-bonded dimeric capsule, based on two concave cyclotriveratrylene (CTV) scaffolds each bearing three self-complementary 2-ureido-4-[<em>1H</em&...
| Autores: | , , , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2016 |
| País: | España |
| Institución: | Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya) |
| Repositorio: | Recercat. Dipósit de la Recerca de Catalunya |
| OAI Identifier: | oai:recercat.cat:2072/305764 |
| Acceso en línea: | http://hdl.handle.net/2072/305764 https://doi.org/10.1002/chem.201601690 |
| Access Level: | acceso abierto |
| Palabra clave: | selective purification of fullerenes, supramolecular chemistry, DFT, density functional theory, NMR, circular dichroism |
| Sumario: | <p> Fullerenes C<sub>60</sub>, C<sub>70</sub>, and C<sub>84</sub> may be readily encaged within a hydrogen-bonded dimeric capsule, based on two concave cyclotriveratrylene (CTV) scaffolds each bearing three self-complementary 2-ureido-4-[<em>1H</em>]-pyrimidinone (UPy) subunits. We herein report NMR and CD studies—complemented by dispersion-corrected density functional theory calculations—aiming to characterize such capsule-fullerene complexes both structurally and energetically. Six fullerenes are considered: in agreement with experiment, calculations find that encapsulation is most favorable for C<sub>84</sub> (on a par with C<sub>90</sub>), and follows the trend C<sub>60</sub><C<sub>70</sub><C<sub>76</sub><C<sub>78</sub><C<sub>84</sub>≈C<sub>90</sub>. As also found by NMR, the most stable capsules are formed by monomers of identical stereochemistry; with UPy and the CTV’s OMe groups in mutual <em>anti</em> orientation; and UPy-CTV ethylene linkers within the capsular surface plane. Up to C<sub>78</sub>, encapsulation is favored by increasing host-guest contacts, but the trend is thereafter increasingly inhibited by growing capsule strain.</p> |
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