Air-stable Curved π-Radical Based on Corannulene: Dynamic Electronic-spin Structure Induced by Temperature-dependent Conformational Changes
Akira Ueda A , Kanako Ogasawara A , Shinsuke Nishida B , Kozo Fukui A , Kazunobu Sato B , Takeji Takui B C , Kazuhiro Nakasuji A and Yasushi Morita A C
+ Author Affiliations
- Author Affiliations
A Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
B Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan.
C Corresponding authors. Email: morita@chem.sci.osaka-u.ac.jp; takui@sci.osaka-cu.ac.jp
Australian Journal of Chemistry 63(12) 1627-1633 https://doi.org/10.1071/CH10280
Submitted: 26 July 2010 Accepted: 1 September 2010 Published: 6 December 2010
Abstract
A new corannulene-based curved neutral π-radical bearing a tert-butylnitroxide moiety has been synthesized and isolated as an air-stable solid. Direct attachment of the spin centre to the corannulene skeleton gives rise to an extensive spin-delocalization onto the curved π-conjugated system from the nitroxide moiety. This salient electronic feature in the curved neutral radical system and its high stability have allowed us to find a dynamic electronic-spin behaviour induced by the temperature-dependent conformational change of the nitroxide moiety, as studied by liquid-phase variable-temperature electron spin resonance and 1H electron-nuclear double resonance and electron-nuclear-nuclear triple resonance spectroscopies with the help of density functional theory calculations.
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