C₇₀ Fullerene charge-transfer interaction with alkylnaphthalenes, pinenes, and a diene

ABSTRACT

Alkylnaphthalenes are not able to form Diels-Alder adducts with C₇₀ fullerene but selected alkylnaphthalenes are able to yield weak charge-transfer complexes (CTC) with C₇₀. More in detail, 1-methylnaphthalene, 2-ethylnaphthalene, and pure naphthalene are not able to produce neither Diels-Alder adducts with C₇₀ fullerene nor CTC. Instead, 1,4-dimethylnaphthalene, 2,6-diethylnaphthalene yield weak 1:1 CTC with C₇₀ fullerene. These CTC are decomposed above ambient temperature. The conjugated diene 2,4-dimethyl-1,3-pentadiene initially forms a weak 1:1 CTC with C₇₀ and evolves into a Diels-Alder multiple adduct where C₇₀ acts as a multisite dienophile.

KEYWORDS:

• alkylnaphthalenes
• α-, β-pinene
• 2,4-dimethyl-1,3-pentadiene
• C₇₀
• charge transfer complexes
• EDA complexes
• electronic absorption spectroscopy

Acknowledgements

We acknowledge support provided by the Spanish Ministry of Economy and Competitiveness (MINECO) under grant AYA-2014-58082-P. D.A.G.H. was funded by the Ramón y Cajal fellowship number RYC-2013-14182.