Properties of Radical Anions of Triptindanones and Indanones: Electronic Communication and Stability of Ion Pairs Containing Lithium Cations

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• 作者：Jan S. Jaworski ; Agnieszka Kosson ; Sł ; awomir Filipek ; Michał ; Koliski ; Dietmar Kuck
• 刊名：Journal of Physical Chemistry C
• 出版年：2009
• 出版时间：April 30, 2009
• 年：2009
• 卷：113
• 期：17
• 页码：7436-7442
• 全文大小：158K
• 年卷期：v.113,no.17(April 30, 2009)
• ISSN：1932-7455

文摘

The properties of radical anions and dianions of three related spatial ketones, 9-triptindanone (T1), 9,10-triptindanedione (T2), and 9,10,11-triptindanetrione (T3), in DMF solutions containing tetraalkylammonium and lithium cations were investigated by electrochemical methods and compared with the properties of radical anions of planar 1-indanone (I1), 1,3-indanedione (I2), and 1,2,3-indanetrione (I3). Electronic communication between carbonyl groups in T2 in the presence of tetraethyl and tetrabutyl cations was found to be two times smaller than for I3, but communication decreases substantially in the presence of Li⁺. Radical anions T1^•− and T2^•− and dianion T2²⁻ that form ion pairs with Li⁺ cations and corresponding association constants K_ass are equal to 493 ± 38, 418 ± 32 and (2.6 ± 0.9) × 10⁷ dm³ mol⁻¹, respectively. The chelating structure of the last ion pair is supported by theoretical calculations of the distribution of the negative charge. A linear relationship between log K_ass and maximum values of the surface charge was observed. For T2, the highest equilibrium constant (log K_disp^I = −2.387 ± 0.064) was found for the disproportionation of the T2^•− radical anion and its ion pair.