Expeditious Preparation of Open-Cage Fullerenes by Rhodium(I)-Catalyzed [2+2+2] Cycloaddition of Diynes and C60: an Experimental and Theoretical Study

A novel methodology to transform C60 into a variety of open-cage fullerene derivatives employing rhodium(I) catalysis has been developed. This transformation encompasses a partially intermolecular [2+2+2] cycloaddition reaction between diynes 1 and C60 to deliver a cyclohexadiene-fused fullerene, wh...

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Detalles Bibliográficos
Autores: Artigas Ruf, Albert, Pla i Quintana, Anna, Lledó Ponsati, Agustí, Roglans i Ribas, Anna, Solà i Puig, Miquel
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2018
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:10256/15814
Acceso en línea:http://hdl.handle.net/10256/15814
Access Level:acceso abierto
Palabra clave:Catàlisi
Catalysis
Addition reactions
Reaccions d'addició
Funcional de densitat, Teoria del
Density functionals
Descripción
Sumario:A novel methodology to transform C60 into a variety of open-cage fullerene derivatives employing rhodium(I) catalysis has been developed. This transformation encompasses a partially intermolecular [2+2+2] cycloaddition reaction between diynes 1 and C60 to deliver a cyclohexadiene-fused fullerene, which concomitantly undergoes a formal [4+4]/retro-[2+2+2] rearrangement to deliver open-cage fullerenes 2. Most notably, this process occurs without the need of photoexcitation. The complete mechanism of this transformation has been rationalized by DFT calculations, which indicate that, after [2+2+2] cycloaddition, the cyclohexadiene-fused intermediate evolves into the final product through a Rh-catalyzed di--methane rearrangement followed by a retro-[2+2+2] cycloaddition. The obtained open-cage fullerenes can be derivatized by Suzuki-Miyaura cross-coupling, or subjected to ring expansion to deliver a 12-membered ring orifice in the fullerene structure. Overall, the methodology presented constitutes a straightforward entry to functional open-cage C60-fullerene derivatives employing catalytic methods