对C-F...M(+) 相互作用的研究:含的子化合物的金属复合物
H Takemura1, S Nakashima, N Kon
1Department of Chemistry, Faculty of Science, Kyushu University, Ropponmatsu 4-2-1, Chuo-ku, Fukuoka, 810-8560 Japan.
Journal of the American Chemical Society
|September 20, 2001
概括
由阴阳双极力驱动的C-F...M(+) 相互作用在使用NMR和晶体学的体化合物中得到证实. 复杂的稳定性取决于金属离子的特性,而不是硬软相互作用,揭示了对甲的洞察力.
科学领域:
- 超分子化学 超分子化学
- 有机金属化学 有机金属化学
- 频谱学是一种光谱学.
背景情况:
- 子化合物与甲单元作为金属子的连接体.
- 了解非共价相互作用在宿主-客人化学中至关重要.
研究的目的:
- 为了研究金属和子化合物之间的C-F...M(+) 相互作用.
- 阐明影响这些复合物的稳定性的因素.
- 描述C-F...M(+) 相互作用的结构和电子特性.
主要方法:
- 核磁共振 (NMR) 光谱学 (1H, 13C, 19F).核磁共振 (NMR) 光谱学 (1H, 13C, 19F).核磁共振 (NMR) 光谱学 (1H, 13C, 19F).核磁共振 (NMR) 光谱学 (1H, 13C, 19F).核磁共振 (NMR) 光谱学 (1H, 13C, 19F).核磁共振 (NMR) 光谱学 (1H, 19F).
- 用各种金属离子 (例如,Tl+,La3+) 进行复杂化研究.
- 进行X射线结晶学分析.
- 布朗方程用于估计债券强度.
- 稳定能量的计算.
主要成果:
- 对所有研究的金属子检测到C-F...M(+) 相互作用,主要作为双极相互作用.
- 复杂稳定性是由金属阴离子特性 (离子半径,水解) 控制的,而不是硬软酸原理.
- 结晶学揭示了复合体中的短C-F...Tl(+) 距离和延长的C-F键.
- 没有溶剂分子协调到La3+在La(3+) 亚集合2复合体.
- 观察到的F-Tl旋转合提供了相互作用的确切证据.
- 与以太氧或氨基相比,化的电子捐赠能力较弱.
结论:
- C-F...M(+) 相互作用是一种阴离子双极相互作用,解释了软金属与含配体的强结合.
- 甲单元的电子捐赠能力有限,导致协调键比率较小.
- 核磁共振光谱和结晶学数据对于描述这种相互作用至关重要.
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