铁结合的酸盐的对比依赖的价值分离
Mio Kondo1, Maai Uchikawa, Kosuke Namiki
1Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|August 7, 2009
概括
在新型铁 - antraquinone 化合物中,价值元化受 counterions 的影响. 这项研究揭示了[1-FcPyl]+部分与PF6 (((-) 等对抗离子之间的静电相互作用可以影响性分离 (VT) 的发生.
科学领域:
- 材料科学 材料科学 材料科学
- 无机化学 无机化学 有机化学
- 超分子化学 超分子化学
背景情况:
- 供体-接受体 (D-A) 结合化合物对于先进的电子材料至关重要.
- 铁素 (Fc) 和 antraquinone (Aq) 部分提供独特的电子和氧化还原特性.
- 了解D-A系统中的结构-属性关系是材料设计的关键.
研究的目的:
- 为了合成和表征新的铁素-乙烯基兰特拉基衍生物.
- 研究 counterions 对这些化合物的电子和结构性质的影响.
- 在固态D-A系统中探索价值分离法 (VT) 的现象.
主要方法:
- 合成的1-ferrocenylethynylanthraquinone (1-FcAq) 和其循环凝结产品,2-ferrocenyloxodihydrodibenzochromenylium盐 ([1-FcPyl]+X-). 在这种过程中,酸盐的合成过程中,酸盐的合成过程中,酸盐的合成过程中,酸盐的合成过程中,酸盐的合成过程中,酸盐的合成过程中.
- 使用电化学方法,紫外线光谱学,单晶X射线分析和TD-DFT计算进行表征.
- 可变温度的Mossbauer光谱学,红外光谱学和X射线粉碎衍射 (XRPD) 来研究VT和结构变化.
主要成果:
- 在[1-FcPyl]+中较大的pi-conjugated系统降低了与1-FcAq.q相比的LUMO水平.
- 在TFSI () 和PF () 盐中观察到Fe () II和Fe () III物种之间的价值分离 (VT),但在BF () (4) () 中没有观察到.
- 异面标识显著影响晶体结构内的二面角,平面性和静电相互作用,影响VT.
结论:
- 在[1-FcPyl]+盐中发生的价值元化很大程度上取决于对抗离子的性质.
- [1-FcPyl]+部分与反离子之间的静电相互作用在稳定或不稳定Fe (III) 种中起着至关重要的作用.
- 像二面角和平面度这样的结构参数由 counterions 调节,影响 D-A 相互作用和 VT 行为.
相关概念视频
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Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
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01:26Photochemical Electrocyclic Reactions: Stereochemistry
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