Tetrathiafulvalene-1,3,5-triazines as (Multi)Donor鈥揂cceptor Systems with Tunable Charge Transfer: Structural, Photophysical, and Theoretical Investigations

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• 作者：Flavia Pop ; Fran莽ois Riob茅 ; Sabine Seifert ; Thomas Cauchy ; Jie Ding ; Nathalie Dupont ; Andreas Hauser ; Marius Koch ; Narcis Avarvari
• 刊名：Inorganic Chemistry
• 出版年：2013
• 出版时间：May 6, 2013
• 年：2013
• 卷：52
• 期：9
• 页码：5023-5034
• 全文大小：649K
• 年卷期：v.52,no.9(May 6, 2013)
• ISSN：1520-510X

文摘

Palladium-catalyzed cross-coupling reactions between chlorinated 1,3,5-triazines (TZ) and tetrathiafulvalene (TTF) trimethyltin derivatives afford mono- and C₃ symmetric tris(TTF)-triazines as donor鈥揳cceptor compounds in which the intramolecular charge transfer (ICT) is modulated by the substitution scheme on TTF and TZ and by chemical or electrochemical oxidation. The TTF-TZ-Cl₂ and (SMe)₂TTF-TZ-Cl₂ derivatives show fully planar structures in the solid state as a consequence of the conjugation between the two units. Electrochemical and photophysical investigations, supported by theoretical calculations, clearly demonstrate that the lowest excited state can be ascribed to the intramolecular charge transfer (ICT) 蟺(TTF)鈫捪€*(TZ) transition. The tris(TTF) compound [(SMe)₂TTF]₃-TZ shows fluorescence when excited in the ICT band, and the emission is quenched upon oxidation. The radical cations TTF^{+鈥?/sup> are easily observed in all of the cases through chemical and electrochemical oxidation by steady-state absorption experiments. In the case of [(SMe)₂TTF]₃-TZ, a low energy band at 5000 cm鈥?, corresponding to a coupling between TTF+鈥?/sup> and TTF units, is observed. A crystalline radical cation salt with the TTF-TZ-Cl₂ donor and PF₆鈥?/sup> anion, prepared by electrocrystallization, is described.}