螺旋式兰化物 (III) 复合物与性非性宏循环
Janusz Gregoliński1, Przemysław Starynowicz, KimNgan T Hua
1Department of Chemistry, University of Wrocław, 14 F. Joliot-Curie, 50-383 Wrocław, Poland.
Journal of the American Chemical Society
|December 5, 2008
概括
螺旋性宏环胺 L 形成反纯螺旋性兰坦化物 (III) 复合体. 这项研究揭示了早期和晚期兰化物具有明显的螺旋偏好,在晚期兰化物复合物的溶液中观察到缓慢的螺旋性逆转.
科学领域:
- 协调化学 协调化学
- 超分子化学 超分子化学
- 兰化物化学 兰化物化学
背景情况:
- 基拉性宏环合体对于创建反纯金属复合体至关重要.
- 兰化物(III) 离子提供独特的电子和磁性特性,可以形成复杂的物体.
- 了解宏循环复合中的立体选择性是开发奇拉材料的关键.
研究的目的:
- 为了合成和表征各种兰化物(III) 离子的enantiopure螺旋复合物与一种合的非亚亚亚马克罗环胺 (L).
- 研究这些复合物的立体化学偏好和溶液行为.
- 为了探索选定的兰化物复合物的光物理性质,以寻找潜在的应用.
主要方法:
- 合成合性非亚马克罗环胺L及其兰坦化物 (III) 复合物.
- 使用光谱方法 (NMR,CD) 和X射线晶体学进行表征.
- 光物理测量包括发光和循环极化发光 (CPL).
主要成果:
- 已经成功地合成了Ce(III),Pr(III),Nd(III),Eu(III),Gd(III),Tb(III),Er(III),Yb(III和Lu(III) 的状复合体.
- X射线结构揭示了明显的热力学螺旋偏好 ((M) 早期Ln, (P) 晚期Ln).
- 核磁共振和核电共振研究表明,对 (M) - 螺旋的动力偏好,在溶液中的晚期兰坦化物中观察到缓慢的螺旋逆转.
- 光物理研究表明,Eu (III) 和Tb (III) 的能量转移效率高,但量子产量低,尽管CPL证实了稳定的性发射物种.
结论:
- 合性宏循环L有效地诱导在兰化物 (III) 复合体中的反纯螺旋结构.
- 在热力学螺旋偏好中,早期和晚期的兰坦化离子之间存在着明确的区别.
- 晚期兰坦化物复合物在溶液中表现出动态的螺旋性反转,突出显示了复杂的立体化学行为.
- 虽然能量传输是高效的,但发光特性受到诸如系统间交叉和非辐射衰变等因素的限制.
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