Lambert Christoph, Schelter Jürgen, Fiebig Torsten, Mank Daniela, Trifonov Anton
Institut für Organische Chemie, Bayerische Julius-Maximilians-Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany.
J Am Chem Soc. 2005 Aug 3;127(30):10600-10. doi: 10.1021/ja0511570.
In this paper, we describe the synthesis and photophysical properties of a series of acridine-triarylamine redox cascades. These cascades were designed in order to promote photoinduced hole transfer from an acridine fluorophore into an adjacent triarylamine. The excited dipolar state then injects a hole into the triarylamine redox cascade. Subsequently, the hole migrates along the redox gradient which was tuned by the substituents attached to the triarylamine redox centers. The rate of hole migration was determined by fluorescence lifetime measurements and is in the ns regime and depends strongly on the solvent polarity. The photophysical processes were also investigated by femtosecond broadband pump-probe spectroscopy. Our studies reveal different dynamic processes in the cascades depending on the solvent polarity, e.g., direct charge separation after photoexcitation vs a two step hole transfer mechanism.
在本文中，我们描述了一系列吖啶 - 三芳基胺氧化还原级联的合成及光物理性质。设计这些级联是为了促进光致空穴从吖啶荧光团转移到相邻的三芳基胺中。激发的偶极态随后将一个空穴注入到三芳基胺氧化还原级联中。随后，空穴沿着由连接到三芳基胺氧化还原中心的取代基调节的氧化还原梯度迁移。空穴迁移速率通过荧光寿命测量确定，处于纳秒量级，并且强烈依赖于溶剂极性。还通过飞秒宽带泵浦 - 探测光谱研究了光物理过程。我们的研究揭示了级联中取决于溶剂极性的不同动态过程，例如光激发后的直接电荷分离与两步空穴转移机制。
